Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Alexei Starovoitov says:

====================
pull-request: bpf-next 2021-09-17

We've added 63 non-merge commits during the last 12 day(s) which contain
a total of 65 files changed, 2653 insertions(+), 751 deletions(-).

The main changes are:

1) Streamline internal BPF program sections handling and
bpf_program__set_attach_target() in libbpf, from Andrii.

2) Add support for new btf kind BTF_KIND_TAG, from Yonghong.

3) Introduce bpf_get_branch_snapshot() to capture LBR, from Song.

4) IMUL optimization for x86-64 JIT, from Jie.

5) xsk selftest improvements, from Magnus.

6) Introduce legacy kprobe events support in libbpf, from Rafael.

7) Access hw timestamp through BPF's __sk_buff, from Vadim.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (63 commits)
selftests/bpf: Fix a few compiler warnings
libbpf: Constify all high-level program attach APIs
libbpf: Schedule open_opts.attach_prog_fd deprecation since v0.7
selftests/bpf: Switch fexit_bpf2bpf selftest to set_attach_target() API
libbpf: Allow skipping attach_func_name in bpf_program__set_attach_target()
libbpf: Deprecated bpf_object_open_opts.relaxed_core_relocs
selftests/bpf: Stop using relaxed_core_relocs which has no effect
libbpf: Use pre-setup sec_def in libbpf_find_attach_btf_id()
bpf: Update bpf_get_smp_processor_id() documentation
libbpf: Add sphinx code documentation comments
selftests/bpf: Skip btf_tag test if btf_tag attribute not supported
docs/bpf: Add documentation for BTF_KIND_TAG
selftests/bpf: Add a test with a bpf program with btf_tag attributes
selftests/bpf: Test BTF_KIND_TAG for deduplication
selftests/bpf: Add BTF_KIND_TAG unit tests
selftests/bpf: Change NAME_NTH/IS_NAME_NTH for BTF_KIND_TAG format
selftests/bpf: Test libbpf API function btf__add_tag()
bpftool: Add support for BTF_KIND_TAG
libbpf: Add support for BTF_KIND_TAG
libbpf: Rename btf_{hash,equal}_int to btf_{hash,equal}_int_tag
...
====================

Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Jakub Kicinski <[e-mail]>

Documentation/bpf/btf.rst

···
     #define BTF_KIND_VAR            14      /* Variable     */
     #define BTF_KIND_DATASEC        15      /* Section      */
     #define BTF_KIND_FLOAT          16      /* Floating point       */
+    #define BTF_KIND_TAG            17      /* Tag          */
 
 Note that the type section encodes debug info, not just pure types.
 ``BTF_KIND_FUNC`` is not a type, and it represents a defined subprogram.
···
          * "size" tells the size of the type it is describing.
          *
          * "type" is used by PTR, TYPEDEF, VOLATILE, CONST, RESTRICT,
-         * FUNC and FUNC_PROTO.
+         * FUNC, FUNC_PROTO and TAG.
          * "type" is a type_id referring to another type.
          */
         union {
···
  * ``size``: the size of the float type in bytes: 2, 4, 8, 12 or 16.
 
 No additional type data follow ``btf_type``.
+
+2.2.17 BTF_KIND_TAG
+~~~~~~~~~~~~~~~~~~~
+
+``struct btf_type`` encoding requirement:
+ * ``name_off``: offset to a non-empty string
+ * ``info.kind_flag``: 0
+ * ``info.kind``: BTF_KIND_TAG
+ * ``info.vlen``: 0
+ * ``type``: ``struct``, ``union``, ``func`` or ``var``
+
+``btf_type`` is followed by ``struct btf_tag``.::
+
+    struct btf_tag {
+        __u32   component_idx;
+    };
+
+The ``name_off`` encodes btf_tag attribute string.
+The ``type`` should be ``struct``, ``union``, ``func`` or ``var``.
+For ``var`` type, ``btf_tag.component_idx`` must be ``-1``.
+For the other three types, if the btf_tag attribute is
+applied to the ``struct``, ``union`` or ``func`` itself,
+``btf_tag.component_idx`` must be ``-1``. Otherwise,
+the attribute is applied to a ``struct``/``union`` member or
+a ``func`` argument, and ``btf_tag.component_idx`` should be a
+valid index (starting from 0) pointing to a member or an argument.
 
 3. BTF Kernel API
 *****************

arch/x86/events/intel/core.c

···
  * However, there are some cases which may change PEBS status, e.g. PMI
  * throttle. The PEBS_ENABLE should be updated where the status changes.
  */
-static void __intel_pmu_disable_all(void)
+static __always_inline void __intel_pmu_disable_all(bool bts)
 {
 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
 
 	wrmsrl(MSR_CORE_PERF_GLOBAL_CTRL, 0);
 
-	if (test_bit(INTEL_PMC_IDX_FIXED_BTS, cpuc->active_mask))
+	if (bts && test_bit(INTEL_PMC_IDX_FIXED_BTS, cpuc->active_mask))
 		intel_pmu_disable_bts();
 }
 
-static void intel_pmu_disable_all(void)
+static __always_inline void intel_pmu_disable_all(void)
 {
-	__intel_pmu_disable_all();
+	__intel_pmu_disable_all(true);
 	intel_pmu_pebs_disable_all();
 	intel_pmu_lbr_disable_all();
 }
···
 {
 	intel_pmu_pebs_enable_all();
 	__intel_pmu_enable_all(added, false);
+}
+
+static noinline int
+__intel_pmu_snapshot_branch_stack(struct perf_branch_entry *entries,
+				  unsigned int cnt, unsigned long flags)
+{
+	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
+
+	intel_pmu_lbr_read();
+	cnt = min_t(unsigned int, cnt, x86_pmu.lbr_nr);
+
+	memcpy(entries, cpuc->lbr_entries, sizeof(struct perf_branch_entry) * cnt);
+	intel_pmu_enable_all(0);
+	local_irq_restore(flags);
+	return cnt;
+}
+
+static int
+intel_pmu_snapshot_branch_stack(struct perf_branch_entry *entries, unsigned int cnt)
+{
+	unsigned long flags;
+
+	/* must not have branches... */
+	local_irq_save(flags);
+	__intel_pmu_disable_all(false); /* we don't care about BTS */
+	__intel_pmu_pebs_disable_all();
+	__intel_pmu_lbr_disable();
+	/*            ... until here */
+	return __intel_pmu_snapshot_branch_stack(entries, cnt, flags);
+}
+
+static int
+intel_pmu_snapshot_arch_branch_stack(struct perf_branch_entry *entries, unsigned int cnt)
+{
+	unsigned long flags;
+
+	/* must not have branches... */
+	local_irq_save(flags);
+	__intel_pmu_disable_all(false); /* we don't care about BTS */
+	__intel_pmu_pebs_disable_all();
+	__intel_pmu_arch_lbr_disable();
+	/*            ... until here */
+	return __intel_pmu_snapshot_branch_stack(entries, cnt, flags);
 }
 
 /*
···
 		apic_write(APIC_LVTPC, APIC_DM_NMI);
 	intel_bts_disable_local();
 	cpuc->enabled = 0;
-	__intel_pmu_disable_all();
+	__intel_pmu_disable_all(true);
 	handled = intel_pmu_drain_bts_buffer();
 	handled += intel_bts_interrupt();
 	status = intel_pmu_get_status();
···
 			x86_pmu.lbr_nr = 0;
 	}
 
-	if (x86_pmu.lbr_nr)
+	if (x86_pmu.lbr_nr) {
 		pr_cont("%d-deep LBR, ", x86_pmu.lbr_nr);
+
+		/* only support branch_stack snapshot for perfmon >= v2 */
+		if (x86_pmu.disable_all == intel_pmu_disable_all) {
+			if (boot_cpu_has(X86_FEATURE_ARCH_LBR)) {
+				static_call_update(perf_snapshot_branch_stack,
+						   intel_pmu_snapshot_arch_branch_stack);
+			} else {
+				static_call_update(perf_snapshot_branch_stack,
+						   intel_pmu_snapshot_branch_stack);
+			}
+		}
+	}
 
 	intel_pmu_check_extra_regs(x86_pmu.extra_regs);
 

arch/x86/events/intel/ds.c

···
 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
 
 	if (cpuc->pebs_enabled)
-		wrmsrl(MSR_IA32_PEBS_ENABLE, 0);
+		__intel_pmu_pebs_disable_all();
 }
 
 static int intel_pmu_pebs_fixup_ip(struct pt_regs *regs)

arch/x86/events/intel/lbr.c

···
 		wrmsrl(MSR_ARCH_LBR_CTL, lbr_select | ARCH_LBR_CTL_LBREN);
 }
 
-static void __intel_pmu_lbr_disable(void)
-{
-	u64 debugctl;
-
-	if (static_cpu_has(X86_FEATURE_ARCH_LBR)) {
-		wrmsrl(MSR_ARCH_LBR_CTL, 0);
-		return;
-	}
-
-	rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctl);
-	debugctl &= ~(DEBUGCTLMSR_LBR | DEBUGCTLMSR_FREEZE_LBRS_ON_PMI);
-	wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctl);
-}
-
 void intel_pmu_lbr_reset_32(void)
 {
 	int i;
···
 {
 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
 
-	if (cpuc->lbr_users && !vlbr_exclude_host())
+	if (cpuc->lbr_users && !vlbr_exclude_host()) {
+		if (static_cpu_has(X86_FEATURE_ARCH_LBR))
+			return __intel_pmu_arch_lbr_disable();
+
 		__intel_pmu_lbr_disable();
+	}
 }
 
 void intel_pmu_lbr_read_32(struct cpu_hw_events *cpuc)

arch/x86/events/perf_event.h

···
 	return intel_pmu_has_bts_period(event, hwc->sample_period);
 }
 
+static __always_inline void __intel_pmu_pebs_disable_all(void)
+{
+	wrmsrl(MSR_IA32_PEBS_ENABLE, 0);
+}
+
+static __always_inline void __intel_pmu_arch_lbr_disable(void)
+{
+	wrmsrl(MSR_ARCH_LBR_CTL, 0);
+}
+
+static __always_inline void __intel_pmu_lbr_disable(void)
+{
+	u64 debugctl;
+
+	rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctl);
+	debugctl &= ~(DEBUGCTLMSR_LBR | DEBUGCTLMSR_FREEZE_LBRS_ON_PMI);
+	wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctl);
+}
+
 int intel_pmu_save_and_restart(struct perf_event *event);
 
 struct event_constraint *

arch/x86/net/bpf_jit_comp.c

···
 			break;
 
 		case BPF_ALU | BPF_MUL | BPF_K:
-		case BPF_ALU | BPF_MUL | BPF_X:
 		case BPF_ALU64 | BPF_MUL | BPF_K:
-		case BPF_ALU64 | BPF_MUL | BPF_X:
-		{
-			bool is64 = BPF_CLASS(insn->code) == BPF_ALU64;
+			if (BPF_CLASS(insn->code) == BPF_ALU64)
+				EMIT1(add_2mod(0x48, dst_reg, dst_reg));
+			else if (is_ereg(dst_reg))
+				EMIT1(add_2mod(0x40, dst_reg, dst_reg));
 
-			if (dst_reg != BPF_REG_0)
-				EMIT1(0x50); /* push rax */
-			if (dst_reg != BPF_REG_3)
-				EMIT1(0x52); /* push rdx */
-
-			/* mov r11, dst_reg */
-			EMIT_mov(AUX_REG, dst_reg);
-
-			if (BPF_SRC(insn->code) == BPF_X)
-				emit_mov_reg(&prog, is64, BPF_REG_0, src_reg);
+			if (is_imm8(imm32))
+				/* imul dst_reg, dst_reg, imm8 */
+				EMIT3(0x6B, add_2reg(0xC0, dst_reg, dst_reg),
+				      imm32);
 			else
-				emit_mov_imm32(&prog, is64, BPF_REG_0, imm32);
-
-			if (is64)
-				EMIT1(add_1mod(0x48, AUX_REG));
-			else if (is_ereg(AUX_REG))
-				EMIT1(add_1mod(0x40, AUX_REG));
-			/* mul(q) r11 */
-			EMIT2(0xF7, add_1reg(0xE0, AUX_REG));
-
-			if (dst_reg != BPF_REG_3)
-				EMIT1(0x5A); /* pop rdx */
-			if (dst_reg != BPF_REG_0) {
-				/* mov dst_reg, rax */
-				EMIT_mov(dst_reg, BPF_REG_0);
-				EMIT1(0x58); /* pop rax */
-			}
+				/* imul dst_reg, dst_reg, imm32 */
+				EMIT2_off32(0x69,
+					    add_2reg(0xC0, dst_reg, dst_reg),
+					    imm32);
 			break;
-		}
+
+		case BPF_ALU | BPF_MUL | BPF_X:
+		case BPF_ALU64 | BPF_MUL | BPF_X:
+			if (BPF_CLASS(insn->code) == BPF_ALU64)
+				EMIT1(add_2mod(0x48, src_reg, dst_reg));
+			else if (is_ereg(dst_reg) || is_ereg(src_reg))
+				EMIT1(add_2mod(0x40, src_reg, dst_reg));
+
+			/* imul dst_reg, src_reg */
+			EMIT3(0x0F, 0xAF, add_2reg(0xC0, src_reg, dst_reg));
+			break;
+
 			/* Shifts */
 		case BPF_ALU | BPF_LSH | BPF_K:
 		case BPF_ALU | BPF_RSH | BPF_K:

include/linux/perf_event.h

···
 #include <linux/cgroup.h>
 #include <linux/refcount.h>
 #include <linux/security.h>
+#include <linux/static_call.h>
 #include <asm/local.h>
 
 struct perf_callchain_entry {
···
 #ifdef CONFIG_MMU
 extern __weak u64 arch_perf_get_page_size(struct mm_struct *mm, unsigned long addr);
 #endif
+
+/*
+ * Snapshot branch stack on software events.
+ *
+ * Branch stack can be very useful in understanding software events. For
+ * example, when a long function, e.g. sys_perf_event_open, returns an
+ * errno, it is not obvious why the function failed. Branch stack could
+ * provide very helpful information in this type of scenarios.
+ *
+ * On software event, it is necessary to stop the hardware branch recorder
+ * fast. Otherwise, the hardware register/buffer will be flushed with
+ * entries of the triggering event. Therefore, static call is used to
+ * stop the hardware recorder.
+ */
+
+/*
+ * cnt is the number of entries allocated for entries.
+ * Return number of entries copied to .
+ */
+typedef int (perf_snapshot_branch_stack_t)(struct perf_branch_entry *entries,
+					   unsigned int cnt);
+DECLARE_STATIC_CALL(perf_snapshot_branch_stack, perf_snapshot_branch_stack_t);
 
 #endif /* _LINUX_PERF_EVENT_H */

include/uapi/linux/bpf.h

···
  * u32 bpf_get_smp_processor_id(void)
  * 	Description
  * 		Get the SMP (symmetric multiprocessing) processor id. Note that
- * 		all programs run with preemption disabled, which means that the
+ * 		all programs run with migration disabled, which means that the
  * 		SMP processor id is stable during all the execution of the
  * 		program.
  * 	Return
···
  *		Get the struct pt_regs associated with **task**.
  *	Return
  *		A pointer to struct pt_regs.
+ *
+ * long bpf_get_branch_snapshot(void *entries, u32 size, u64 flags)
+ *	Description
+ *		Get branch trace from hardware engines like Intel LBR. The
+ *		hardware engine is stopped shortly after the helper is
+ *		called. Therefore, the user need to filter branch entries
+ *		based on the actual use case. To capture branch trace
+ *		before the trigger point of the BPF program, the helper
+ *		should be called at the beginning of the BPF program.
+ *
+ *		The data is stored as struct perf_branch_entry into output
+ *		buffer *entries*. *size* is the size of *entries* in bytes.
+ *		*flags* is reserved for now and must be zero.
+ *
+ *	Return
+ *		On success, number of bytes written to *buf*. On error, a
+ *		negative value.
+ *
+ *		**-EINVAL** if *flags* is not zero.
+ *
+ *		**-ENOENT** if architecture does not support branch records.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
···
 	FN(get_func_ip),		\
 	FN(get_attach_cookie),		\
 	FN(task_pt_regs),		\
+	FN(get_branch_snapshot),	\
 	/* */
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
···
 	__u32 gso_segs;
 	__bpf_md_ptr(struct bpf_sock *, sk);
 	__u32 gso_size;
+	__u32 :32;		/* Padding, future use. */
+	__u64 hwtstamp;
 };
 
 struct bpf_tunnel_key {

include/uapi/linux/btf.h

···
 	 * "size" tells the size of the type it is describing.
 	 *
 	 * "type" is used by PTR, TYPEDEF, VOLATILE, CONST, RESTRICT,
-	 * FUNC, FUNC_PROTO and VAR.
+	 * FUNC, FUNC_PROTO, VAR and TAG.
 	 * "type" is a type_id referring to another type.
 	 */
 	union {
···
 #define BTF_INFO_VLEN(info)	((info) & 0xffff)
 #define BTF_INFO_KFLAG(info)	((info) >> 31)
 
-#define BTF_KIND_UNKN		0	/* Unknown	*/
-#define BTF_KIND_INT		1	/* Integer	*/
-#define BTF_KIND_PTR		2	/* Pointer	*/
-#define BTF_KIND_ARRAY		3	/* Array	*/
-#define BTF_KIND_STRUCT		4	/* Struct	*/
-#define BTF_KIND_UNION		5	/* Union	*/
-#define BTF_KIND_ENUM		6	/* Enumeration	*/
-#define BTF_KIND_FWD		7	/* Forward	*/
-#define BTF_KIND_TYPEDEF	8	/* Typedef	*/
-#define BTF_KIND_VOLATILE	9	/* Volatile	*/
-#define BTF_KIND_CONST		10	/* Const	*/
-#define BTF_KIND_RESTRICT	11	/* Restrict	*/
-#define BTF_KIND_FUNC		12	/* Function	*/
-#define BTF_KIND_FUNC_PROTO	13	/* Function Proto	*/
-#define BTF_KIND_VAR		14	/* Variable	*/
-#define BTF_KIND_DATASEC	15	/* Section	*/
-#define BTF_KIND_FLOAT		16	/* Floating point	*/
-#define BTF_KIND_MAX		BTF_KIND_FLOAT
-#define NR_BTF_KINDS		(BTF_KIND_MAX + 1)
+enum {
+	BTF_KIND_UNKN		= 0,	/* Unknown	*/
+	BTF_KIND_INT		= 1,	/* Integer	*/
+	BTF_KIND_PTR		= 2,	/* Pointer	*/
+	BTF_KIND_ARRAY		= 3,	/* Array	*/
+	BTF_KIND_STRUCT		= 4,	/* Struct	*/
+	BTF_KIND_UNION		= 5,	/* Union	*/
+	BTF_KIND_ENUM		= 6,	/* Enumeration	*/
+	BTF_KIND_FWD		= 7,	/* Forward	*/
+	BTF_KIND_TYPEDEF	= 8,	/* Typedef	*/
+	BTF_KIND_VOLATILE	= 9,	/* Volatile	*/
+	BTF_KIND_CONST		= 10,	/* Const	*/
+	BTF_KIND_RESTRICT	= 11,	/* Restrict	*/
+	BTF_KIND_FUNC		= 12,	/* Function	*/
+	BTF_KIND_FUNC_PROTO	= 13,	/* Function Proto	*/
+	BTF_KIND_VAR		= 14,	/* Variable	*/
+	BTF_KIND_DATASEC	= 15,	/* Section	*/
+	BTF_KIND_FLOAT		= 16,	/* Floating point	*/
+	BTF_KIND_TAG		= 17,	/* Tag */
+
+	NR_BTF_KINDS,
+	BTF_KIND_MAX		= NR_BTF_KINDS - 1,
+};
 
 /* For some specific BTF_KIND, "struct btf_type" is immediately
  * followed by extra data.
···
 	__u32	type;
 	__u32	offset;
 	__u32	size;
+};
+
+/* BTF_KIND_TAG is followed by a single "struct btf_tag" to describe
+ * additional information related to the tag applied location.
+ * If component_idx == -1, the tag is applied to a struct, union,
+ * variable or function. Otherwise, it is applied to a struct/union
+ * member or a func argument, and component_idx indicates which member
+ * or argument (0 ... vlen-1).
+ */
+struct btf_tag {
+       __s32   component_idx;
 };
 
 #endif /* _UAPI__LINUX_BTF_H__ */

kernel/bpf/btf.c

···
 	[BTF_KIND_VAR]		= "VAR",
 	[BTF_KIND_DATASEC]	= "DATASEC",
 	[BTF_KIND_FLOAT]	= "FLOAT",
+	[BTF_KIND_TAG]		= "TAG",
 };
 
 const char *btf_type_str(const struct btf_type *t)
···
 	return BTF_INFO_KIND(t->info) == BTF_KIND_DATASEC;
 }
 
+static bool btf_type_is_tag(const struct btf_type *t)
+{
+	return BTF_INFO_KIND(t->info) == BTF_KIND_TAG;
+}
+
+static bool btf_type_is_tag_target(const struct btf_type *t)
+{
+	return btf_type_is_func(t) || btf_type_is_struct(t) ||
+	       btf_type_is_var(t);
+}
+
 u32 btf_nr_types(const struct btf *btf)
 {
 	u32 total = 0;
···
 static bool btf_type_is_resolve_source_only(const struct btf_type *t)
 {
 	return btf_type_is_var(t) ||
+	       btf_type_is_tag(t) ||
 	       btf_type_is_datasec(t);
 }
 
···
 	       btf_type_is_struct(t) ||
 	       btf_type_is_array(t) ||
 	       btf_type_is_var(t) ||
+	       btf_type_is_tag(t) ||
 	       btf_type_is_datasec(t);
 }
 
···
 static const struct btf_var *btf_type_var(const struct btf_type *t)
 {
 	return (const struct btf_var *)(t + 1);
+}
+
+static const struct btf_tag *btf_type_tag(const struct btf_type *t)
+{
+	return (const struct btf_tag *)(t + 1);
 }
 
 static const struct btf_kind_operations *btf_type_ops(const struct btf_type *t)
···
 	.show = btf_df_show,
 };
 
+static s32 btf_tag_check_meta(struct btf_verifier_env *env,
+			      const struct btf_type *t,
+			      u32 meta_left)
+{
+	const struct btf_tag *tag;
+	u32 meta_needed = sizeof(*tag);
+	s32 component_idx;
+	const char *value;
+
+	if (meta_left < meta_needed) {
+		btf_verifier_log_basic(env, t,
+				       "meta_left:%u meta_needed:%u",
+				       meta_left, meta_needed);
+		return -EINVAL;
+	}
+
+	value = btf_name_by_offset(env->btf, t->name_off);
+	if (!value || !value[0]) {
+		btf_verifier_log_type(env, t, "Invalid value");
+		return -EINVAL;
+	}
+
+	if (btf_type_vlen(t)) {
+		btf_verifier_log_type(env, t, "vlen != 0");
+		return -EINVAL;
+	}
+
+	if (btf_type_kflag(t)) {
+		btf_verifier_log_type(env, t, "Invalid btf_info kind_flag");
+		return -EINVAL;
+	}
+
+	component_idx = btf_type_tag(t)->component_idx;
+	if (component_idx < -1) {
+		btf_verifier_log_type(env, t, "Invalid component_idx");
+		return -EINVAL;
+	}
+
+	btf_verifier_log_type(env, t, NULL);
+
+	return meta_needed;
+}
+
+static int btf_tag_resolve(struct btf_verifier_env *env,
+			   const struct resolve_vertex *v)
+{
+	const struct btf_type *next_type;
+	const struct btf_type *t = v->t;
+	u32 next_type_id = t->type;
+	struct btf *btf = env->btf;
+	s32 component_idx;
+	u32 vlen;
+
+	next_type = btf_type_by_id(btf, next_type_id);
+	if (!next_type || !btf_type_is_tag_target(next_type)) {
+		btf_verifier_log_type(env, v->t, "Invalid type_id");
+		return -EINVAL;
+	}
+
+	if (!env_type_is_resolve_sink(env, next_type) &&
+	    !env_type_is_resolved(env, next_type_id))
+		return env_stack_push(env, next_type, next_type_id);
+
+	component_idx = btf_type_tag(t)->component_idx;
+	if (component_idx != -1) {
+		if (btf_type_is_var(next_type)) {
+			btf_verifier_log_type(env, v->t, "Invalid component_idx");
+			return -EINVAL;
+		}
+
+		if (btf_type_is_struct(next_type)) {
+			vlen = btf_type_vlen(next_type);
+		} else {
+			/* next_type should be a function */
+			next_type = btf_type_by_id(btf, next_type->type);
+			vlen = btf_type_vlen(next_type);
+		}
+
+		if ((u32)component_idx >= vlen) {
+			btf_verifier_log_type(env, v->t, "Invalid component_idx");
+			return -EINVAL;
+		}
+	}
+
+	env_stack_pop_resolved(env, next_type_id, 0);
+
+	return 0;
+}
+
+static void btf_tag_log(struct btf_verifier_env *env, const struct btf_type *t)
+{
+	btf_verifier_log(env, "type=%u component_idx=%d", t->type,
+			 btf_type_tag(t)->component_idx);
+}
+
+static const struct btf_kind_operations tag_ops = {
+	.check_meta = btf_tag_check_meta,
+	.resolve = btf_tag_resolve,
+	.check_member = btf_df_check_member,
+	.check_kflag_member = btf_df_check_kflag_member,
+	.log_details = btf_tag_log,
+	.show = btf_df_show,
+};
+
 static int btf_func_proto_check(struct btf_verifier_env *env,
 				const struct btf_type *t)
 {
···
 	[BTF_KIND_VAR] = &var_ops,
 	[BTF_KIND_DATASEC] = &datasec_ops,
 	[BTF_KIND_FLOAT] = &float_ops,
+	[BTF_KIND_TAG] = &tag_ops,
 };
 
 static s32 btf_check_meta(struct btf_verifier_env *env,
···
 
 	if (btf_type_is_struct(t) || btf_type_is_datasec(t))
 		return !btf_resolved_type_id(btf, type_id) &&
+		       !btf_resolved_type_size(btf, type_id);
+
+	if (btf_type_is_tag(t))
+		return btf_resolved_type_id(btf, type_id) &&
 		       !btf_resolved_type_size(btf, type_id);
 
 	if (btf_type_is_modifier(t) || btf_type_is_ptr(t) ||

kernel/bpf/trampoline.c

···
 #include <linux/rcupdate_trace.h>
 #include <linux/rcupdate_wait.h>
 #include <linux/module.h>
+#include <linux/static_call.h>
 
 /* dummy _ops. The verifier will operate on target program's ops. */
 const struct bpf_verifier_ops bpf_extension_verifier_ops = {
···
 }
 
 #define NO_START_TIME 1
-static u64 notrace bpf_prog_start_time(void)
+static __always_inline u64 notrace bpf_prog_start_time(void)
 {
 	u64 start = NO_START_TIME;
 

kernel/events/core.c

···
 	.threaded	= true,
 };
 #endif /* CONFIG_CGROUP_PERF */
+
+DEFINE_STATIC_CALL_RET0(perf_snapshot_branch_stack, perf_snapshot_branch_stack_t);

kernel/trace/bpf_trace.c

···
 	.arg1_type	= ARG_PTR_TO_CTX,
 };
 
+BPF_CALL_3(bpf_get_branch_snapshot, void *, buf, u32, size, u64, flags)
+{
+#ifndef CONFIG_X86
+	return -ENOENT;
+#else
+	static const u32 br_entry_size = sizeof(struct perf_branch_entry);
+	u32 entry_cnt = size / br_entry_size;
+
+	entry_cnt = static_call(perf_snapshot_branch_stack)(buf, entry_cnt);
+
+	if (unlikely(flags))
+		return -EINVAL;
+
+	if (!entry_cnt)
+		return -ENOENT;
+
+	return entry_cnt * br_entry_size;
+#endif
+}
+
+static const struct bpf_func_proto bpf_get_branch_snapshot_proto = {
+	.func		= bpf_get_branch_snapshot,
+	.gpl_only	= true,
+	.ret_type	= RET_INTEGER,
+	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
+	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
+};
+
 static const struct bpf_func_proto *
 bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 {
···
 		return &bpf_snprintf_proto;
 	case BPF_FUNC_get_func_ip:
 		return &bpf_get_func_ip_proto_tracing;
+	case BPF_FUNC_get_branch_snapshot:
+		return &bpf_get_branch_snapshot_proto;
 	default:
 		return bpf_base_func_proto(func_id);
 	}

lib/test_bpf.c

···
 	skb_shinfo(skb[0])->gso_type |= SKB_GSO_DODGY;
 	skb_shinfo(skb[0])->gso_segs = 0;
 	skb_shinfo(skb[0])->frag_list = skb[1];
+	skb_shinfo(skb[0])->hwtstamps.hwtstamp = 1000;
 
 	/* adjust skb[0]'s len */
 	skb[0]->len += skb[1]->len;

net/bpf/test_run.c

···
 		return -EINVAL;
 
 	/* priority is allowed */
-
-	if (!range_is_zero(__skb, offsetofend(struct __sk_buff, priority),
-			   offsetof(struct __sk_buff, ifindex)))
-		return -EINVAL;
-
+	/* ingress_ifindex is allowed */
 	/* ifindex is allowed */
 
 	if (!range_is_zero(__skb, offsetofend(struct __sk_buff, ifindex),
···
 	/* gso_size is allowed */
 
 	if (!range_is_zero(__skb, offsetofend(struct __sk_buff, gso_size),
+			   offsetof(struct __sk_buff, hwtstamp)))
+		return -EINVAL;
+
+	/* hwtstamp is allowed */
+
+	if (!range_is_zero(__skb, offsetofend(struct __sk_buff, hwtstamp),
 			   sizeof(struct __sk_buff)))
 		return -EINVAL;
 
 	skb->mark = __skb->mark;
 	skb->priority = __skb->priority;
+	skb->skb_iif = __skb->ingress_ifindex;
 	skb->tstamp = __skb->tstamp;
 	memcpy(&cb->data, __skb->cb, QDISC_CB_PRIV_LEN);
 
···
 		return -EINVAL;
 	skb_shinfo(skb)->gso_segs = __skb->gso_segs;
 	skb_shinfo(skb)->gso_size = __skb->gso_size;
+	skb_shinfo(skb)->hwtstamps.hwtstamp = __skb->hwtstamp;
 
 	return 0;
 }
···
 
 	__skb->mark = skb->mark;
 	__skb->priority = skb->priority;
+	__skb->ingress_ifindex = skb->skb_iif;
 	__skb->ifindex = skb->dev->ifindex;
 	__skb->tstamp = skb->tstamp;
 	memcpy(__skb->cb, &cb->data, QDISC_CB_PRIV_LEN);
 	__skb->wire_len = cb->pkt_len;
 	__skb->gso_segs = skb_shinfo(skb)->gso_segs;
+	__skb->hwtstamp = skb_shinfo(skb)->hwtstamps.hwtstamp;
 }
 
 int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr,

net/core/filter.c

···
 		break;
 	case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
 		return false;
+	case bpf_ctx_range(struct __sk_buff, hwtstamp):
+		if (type == BPF_WRITE || size != sizeof(__u64))
+			return false;
+		break;
 	case bpf_ctx_range(struct __sk_buff, tstamp):
 		if (size != sizeof(__u64))
 			return false;
···
 			return false;
 		info->reg_type = PTR_TO_SOCK_COMMON_OR_NULL;
 		break;
+	case offsetofend(struct __sk_buff, gso_size) ... offsetof(struct __sk_buff, hwtstamp) - 1:
+		/* Explicitly prohibit access to padding in __sk_buff. */
+		return false;
 	default:
 		/* Only narrow read access allowed for now. */
 		if (type == BPF_WRITE) {
···
 	case bpf_ctx_range_till(struct __sk_buff, family, local_port):
 	case bpf_ctx_range(struct __sk_buff, tstamp):
 	case bpf_ctx_range(struct __sk_buff, wire_len):
+	case bpf_ctx_range(struct __sk_buff, hwtstamp):
 		return false;
 	}
 
···
 	case bpf_ctx_range(struct __sk_buff, data_meta):
 	case bpf_ctx_range(struct __sk_buff, tstamp):
 	case bpf_ctx_range(struct __sk_buff, wire_len):
+	case bpf_ctx_range(struct __sk_buff, hwtstamp):
 		return false;
 	}
 
···
 	case bpf_ctx_range(struct __sk_buff, data_meta):
 	case bpf_ctx_range(struct __sk_buff, tstamp):
 	case bpf_ctx_range(struct __sk_buff, wire_len):
+	case bpf_ctx_range(struct __sk_buff, hwtstamp):
 		return false;
 	}
 
···
 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
 				      si->dst_reg, si->src_reg,
 				      offsetof(struct sk_buff, sk));
+		break;
+	case offsetof(struct __sk_buff, hwtstamp):
+		BUILD_BUG_ON(sizeof_field(struct skb_shared_hwtstamps, hwtstamp) != 8);
+		BUILD_BUG_ON(offsetof(struct skb_shared_hwtstamps, hwtstamp) != 0);
+
+		insn = bpf_convert_shinfo_access(si, insn);
+		*insn++ = BPF_LDX_MEM(BPF_DW,
+				      si->dst_reg, si->dst_reg,
+				      bpf_target_off(struct skb_shared_info,
+						     hwtstamps, 8,
+						     target_size));
 		break;
 	}
 

tools/bpf/bpftool/Makefile

···
 BPFTOOL_BOOTSTRAP := $(BOOTSTRAP_OUTPUT)bpftool
 
 BOOTSTRAP_OBJS = $(addprefix $(BOOTSTRAP_OUTPUT),main.o common.o json_writer.o gen.o btf.o xlated_dumper.o btf_dumper.o disasm.o)
+$(BOOTSTRAP_OBJS): $(LIBBPF_BOOTSTRAP)
+
 OBJS = $(patsubst %.c,$(OUTPUT)%.o,$(SRCS)) $(OUTPUT)disasm.o
+$(OBJS): $(LIBBPF)
 
 VMLINUX_BTF_PATHS ?= $(if $(O),$(O)/vmlinux)				\
 		     $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux)	\

tools/bpf/bpftool/btf.c

···
 	[BTF_KIND_VAR]		= "VAR",
 	[BTF_KIND_DATASEC]	= "DATASEC",
 	[BTF_KIND_FLOAT]	= "FLOAT",
+	[BTF_KIND_TAG]		= "TAG",
 };
 
 struct btf_attach_table {
···
 			jsonw_uint_field(w, "size", t->size);
 		else
 			printf(" size=%u", t->size);
+		break;
+	}
+	case BTF_KIND_TAG: {
+		const struct btf_tag *tag = (const void *)(t + 1);
+
+		if (json_output) {
+			jsonw_uint_field(w, "type_id", t->type);
+			jsonw_int_field(w, "component_idx", tag->component_idx);
+		} else {
+			printf(" type_id=%u component_idx=%d", t->type, tag->component_idx);
+		}
 		break;
 	}
 	default:

tools/bpf/bpftool/gen.c

···
 		} else if (c == '\n') {
 			break;
 		} else {
-			p_err("unrecognized character at pos %td in template '%s'",
-			      src - template - 1, template);
+			p_err("unrecognized character at pos %td in template '%s': '%c'",
+			      src - template - 1, template, c);
 			free(s);
 			exit(-1);
 		}
···
 	}
 
 	bpf_object__for_each_map(map, obj) {
-		const char * ident;
+		const char *ident;
 
 		ident = get_map_ident(map);
 		if (!ident)
···
 	codegen("\
 		\n\
 									    \n\
+		static inline const void *%1$s__elf_bytes(size_t *sz);	    \n\
+									    \n\
 		static inline int					    \n\
 		%1$s__create_skeleton(struct %1$s *obj)			    \n\
 		{							    \n\
···
 	codegen("\
 		\n\
 									    \n\
-			s->data_sz = %d;				    \n\
-			s->data = (void *)\"\\				    \n\
-		",
-		file_sz);
+			s->data = (void *)%2$s__elf_bytes(&s->data_sz);	    \n\
+									    \n\
+			return 0;					    \n\
+		err:							    \n\
+			bpf_object__destroy_skeleton(s);		    \n\
+			return -ENOMEM;					    \n\
+		}							    \n\
+									    \n\
+		static inline const void *%2$s__elf_bytes(size_t *sz)	    \n\
+		{							    \n\
+			*sz = %1$d;					    \n\
+			return (const void *)\"\\			    \n\
+		"
+		, file_sz, obj_name);
 
 	/* embed contents of BPF object file */
 	print_hex(obj_data, file_sz);
···
 	codegen("\
 		\n\
 		\";							    \n\
-									    \n\
-			return 0;					    \n\
-		err:							    \n\
-			bpf_object__destroy_skeleton(s);		    \n\
-			return -ENOMEM;					    \n\
 		}							    \n\
 									    \n\
 		#endif /* %s */						    \n\

tools/bpf/resolve_btfids/Makefile

···
 SUBCMD_SRC := $(srctree)/tools/lib/subcmd/
 
 BPFOBJ     := $(OUTPUT)/libbpf/libbpf.a
+LIBBPF_OUT := $(abspath $(dir $(BPFOBJ)))/
 SUBCMDOBJ  := $(OUTPUT)/libsubcmd/libsubcmd.a
 
 BINARY     := $(OUTPUT)/resolve_btfids
···
 	$(Q)$(MAKE) -C $(SUBCMD_SRC) OUTPUT=$(abspath $(dir $@))/ $(abspath $@)
 
 $(BPFOBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(OUTPUT)/libbpf
-	$(Q)$(MAKE) $(submake_extras) -C $(LIBBPF_SRC)  OUTPUT=$(abspath $(dir $@))/ $(abspath $@)
+	$(Q)$(MAKE) $(submake_extras) -C $(LIBBPF_SRC)  OUTPUT=$(LIBBPF_OUT) $(abspath $@)
 
 CFLAGS := -g \
           -I$(srctree)/tools/include \
···
 export srctree OUTPUT CFLAGS Q
 include $(srctree)/tools/build/Makefile.include
 
-$(BINARY_IN): fixdep FORCE | $(OUTPUT)
+$(BINARY_IN): $(BPFOBJ) fixdep FORCE | $(OUTPUT)
 	$(Q)$(MAKE) $(build)=resolve_btfids
 
 $(BINARY): $(BPFOBJ) $(SUBCMDOBJ) $(BINARY_IN)

tools/include/uapi/linux/bpf.h

···
  * u32 bpf_get_smp_processor_id(void)
  * 	Description
  * 		Get the SMP (symmetric multiprocessing) processor id. Note that
- * 		all programs run with preemption disabled, which means that the
+ * 		all programs run with migration disabled, which means that the
  * 		SMP processor id is stable during all the execution of the
  * 		program.
  * 	Return
···
  *		Get the struct pt_regs associated with **task**.
  *	Return
  *		A pointer to struct pt_regs.
+ *
+ * long bpf_get_branch_snapshot(void *entries, u32 size, u64 flags)
+ *	Description
+ *		Get branch trace from hardware engines like Intel LBR. The
+ *		hardware engine is stopped shortly after the helper is
+ *		called. Therefore, the user need to filter branch entries
+ *		based on the actual use case. To capture branch trace
+ *		before the trigger point of the BPF program, the helper
+ *		should be called at the beginning of the BPF program.
+ *
+ *		The data is stored as struct perf_branch_entry into output
+ *		buffer *entries*. *size* is the size of *entries* in bytes.
+ *		*flags* is reserved for now and must be zero.
+ *
+ *	Return
+ *		On success, number of bytes written to *buf*. On error, a
+ *		negative value.
+ *
+ *		**-EINVAL** if *flags* is not zero.
+ *
+ *		**-ENOENT** if architecture does not support branch records.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
···
 	FN(get_func_ip),		\
 	FN(get_attach_cookie),		\
 	FN(task_pt_regs),		\
+	FN(get_branch_snapshot),	\
 	/* */
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
···
 	__u32 gso_segs;
 	__bpf_md_ptr(struct bpf_sock *, sk);
 	__u32 gso_size;
+	__u32 :32;		/* Padding, future use. */
+	__u64 hwtstamp;
 };
 
 struct bpf_tunnel_key {

tools/include/uapi/linux/btf.h

···
 	 * "size" tells the size of the type it is describing.
 	 *
 	 * "type" is used by PTR, TYPEDEF, VOLATILE, CONST, RESTRICT,
-	 * FUNC, FUNC_PROTO and VAR.
+	 * FUNC, FUNC_PROTO, VAR and TAG.
 	 * "type" is a type_id referring to another type.
 	 */
 	union {
···
 #define BTF_INFO_VLEN(info)	((info) & 0xffff)
 #define BTF_INFO_KFLAG(info)	((info) >> 31)
 
-#define BTF_KIND_UNKN		0	/* Unknown	*/
-#define BTF_KIND_INT		1	/* Integer	*/
-#define BTF_KIND_PTR		2	/* Pointer	*/
-#define BTF_KIND_ARRAY		3	/* Array	*/
-#define BTF_KIND_STRUCT		4	/* Struct	*/
-#define BTF_KIND_UNION		5	/* Union	*/
-#define BTF_KIND_ENUM		6	/* Enumeration	*/
-#define BTF_KIND_FWD		7	/* Forward	*/
-#define BTF_KIND_TYPEDEF	8	/* Typedef	*/
-#define BTF_KIND_VOLATILE	9	/* Volatile	*/
-#define BTF_KIND_CONST		10	/* Const	*/
-#define BTF_KIND_RESTRICT	11	/* Restrict	*/
-#define BTF_KIND_FUNC		12	/* Function	*/
-#define BTF_KIND_FUNC_PROTO	13	/* Function Proto	*/
-#define BTF_KIND_VAR		14	/* Variable	*/
-#define BTF_KIND_DATASEC	15	/* Section	*/
-#define BTF_KIND_FLOAT		16	/* Floating point	*/
-#define BTF_KIND_MAX		BTF_KIND_FLOAT
-#define NR_BTF_KINDS		(BTF_KIND_MAX + 1)
+enum {
+	BTF_KIND_UNKN		= 0,	/* Unknown	*/
+	BTF_KIND_INT		= 1,	/* Integer	*/
+	BTF_KIND_PTR		= 2,	/* Pointer	*/
+	BTF_KIND_ARRAY		= 3,	/* Array	*/
+	BTF_KIND_STRUCT		= 4,	/* Struct	*/
+	BTF_KIND_UNION		= 5,	/* Union	*/
+	BTF_KIND_ENUM		= 6,	/* Enumeration	*/
+	BTF_KIND_FWD		= 7,	/* Forward	*/
+	BTF_KIND_TYPEDEF	= 8,	/* Typedef	*/
+	BTF_KIND_VOLATILE	= 9,	/* Volatile	*/
+	BTF_KIND_CONST		= 10,	/* Const	*/
+	BTF_KIND_RESTRICT	= 11,	/* Restrict	*/
+	BTF_KIND_FUNC		= 12,	/* Function	*/
+	BTF_KIND_FUNC_PROTO	= 13,	/* Function Proto	*/
+	BTF_KIND_VAR		= 14,	/* Variable	*/
+	BTF_KIND_DATASEC	= 15,	/* Section	*/
+	BTF_KIND_FLOAT		= 16,	/* Floating point	*/
+	BTF_KIND_TAG		= 17,	/* Tag */
+
+	NR_BTF_KINDS,
+	BTF_KIND_MAX		= NR_BTF_KINDS - 1,
+};
 
 /* For some specific BTF_KIND, "struct btf_type" is immediately
  * followed by extra data.
···
 	__u32	type;
 	__u32	offset;
 	__u32	size;
+};
+
+/* BTF_KIND_TAG is followed by a single "struct btf_tag" to describe
+ * additional information related to the tag applied location.
+ * If component_idx == -1, the tag is applied to a struct, union,
+ * variable or function. Otherwise, it is applied to a struct/union
+ * member or a func argument, and component_idx indicates which member
+ * or argument (0 ... vlen-1).
+ */
+struct btf_tag {
+       __s32   component_idx;
 };
 
 #endif /* _UAPI__LINUX_BTF_H__ */

tools/lib/bpf/.gitignore

···
 # SPDX-License-Identifier: GPL-2.0-only
-libbpf_version.h
 libbpf.pc
 libbpf.so.*
 TAGS

tools/lib/bpf/Makefile

···
 LIBBPF_VERSION := $(shell \
 	grep -oE '^LIBBPF_([0-9.]+)' $(VERSION_SCRIPT) | \
 	sort -rV | head -n1 | cut -d'_' -f2)
-LIBBPF_MAJOR_VERSION := $(firstword $(subst ., ,$(LIBBPF_VERSION)))
+LIBBPF_MAJOR_VERSION := $(word 1,$(subst ., ,$(LIBBPF_VERSION)))
+LIBBPF_MINOR_VERSION := $(word 2,$(subst ., ,$(LIBBPF_VERSION)))
 
 MAKEFLAGS += --no-print-directory
 
···
   VERBOSE = 0
 endif
 
-INCLUDES = -I. -I$(srctree)/tools/include -I$(srctree)/tools/include/uapi
+INCLUDES = -I$(if $(OUTPUT),$(OUTPUT),.)				\
+	   -I$(srctree)/tools/include -I$(srctree)/tools/include/uapi
 
 export prefix libdir src obj
 
···
 BPF_IN_SHARED	:= $(SHARED_OBJDIR)libbpf-in.o
 BPF_IN_STATIC	:= $(STATIC_OBJDIR)libbpf-in.o
 BPF_HELPER_DEFS	:= $(OUTPUT)bpf_helper_defs.h
+BPF_GENERATED	:= $(BPF_HELPER_DEFS)
 
 LIB_TARGET	:= $(addprefix $(OUTPUT),$(LIB_TARGET))
 LIB_FILE	:= $(addprefix $(OUTPUT),$(LIB_FILE))
···
 
 all_cmd: $(CMD_TARGETS) check
 
-$(BPF_IN_SHARED): force $(BPF_HELPER_DEFS)
+$(BPF_IN_SHARED): force $(BPF_GENERATED)
 	@(test -f ../../include/uapi/linux/bpf.h -a -f ../../../include/uapi/linux/bpf.h && ( \
 	(diff -B ../../include/uapi/linux/bpf.h ../../../include/uapi/linux/bpf.h >/dev/null) || \
 	echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/bpf.h' differs from latest version at 'include/uapi/linux/bpf.h'" >&2 )) || true
···
 	echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/if_xdp.h' differs from latest version at 'include/uapi/linux/if_xdp.h'" >&2 )) || true
 	$(Q)$(MAKE) $(build)=libbpf OUTPUT=$(SHARED_OBJDIR) CFLAGS="$(CFLAGS) $(SHLIB_FLAGS)"
 
-$(BPF_IN_STATIC): force $(BPF_HELPER_DEFS)
+$(BPF_IN_STATIC): force $(BPF_GENERATED)
 	$(Q)$(MAKE) $(build)=libbpf OUTPUT=$(STATIC_OBJDIR)
 
 $(BPF_HELPER_DEFS): $(srctree)/tools/include/uapi/linux/bpf.h
···
 		-e "s|@VERSION@|$(LIBBPF_VERSION)|" \
 		< libbpf.pc.template > $@
 
-check: check_abi
+check: check_abi check_version
 
 check_abi: $(OUTPUT)libbpf.so $(VERSION_SCRIPT)
 	@if [ "$(GLOBAL_SYM_COUNT)" != "$(VERSIONED_SYM_COUNT)" ]; then	 \
···
 		exit 1;							 \
 	fi
 
+HDR_MAJ_VERSION := $(shell grep -oE '^\#define LIBBPF_MAJOR_VERSION ([0-9]+)$$' libbpf_version.h | cut -d' ' -f3)
+HDR_MIN_VERSION := $(shell grep -oE '^\#define LIBBPF_MINOR_VERSION ([0-9]+)$$' libbpf_version.h | cut -d' ' -f3)
+
+check_version: $(VERSION_SCRIPT) libbpf_version.h
+	@if [ "$(HDR_MAJ_VERSION)" != "$(LIBBPF_MAJOR_VERSION)" ]; then        \
+		echo "Error: libbpf major version mismatch detected: "	       \
+		     "'$(HDR_MAJ_VERSION)' != '$(LIBBPF_MAJOR_VERSION)'" >&2;  \
+		exit 1;							       \
+	fi
+	@if [ "$(HDR_MIN_VERSION)" != "$(LIBBPF_MINOR_VERSION)" ]; then	       \
+		echo "Error: libbpf minor version mismatch detected: "	       \
+		     "'$(HDR_MIN_VERSION)' != '$(LIBBPF_MINOR_VERSION)'" >&2;  \
+		exit 1;							       \
+	fi
+
 define do_install_mkdir
 	if [ ! -d '$(DESTDIR_SQ)$1' ]; then		\
 		$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$1';	\
···
 		cp -fpR $(LIB_FILE) $(DESTDIR)$(libdir_SQ)
 
 INSTALL_HEADERS = bpf.h libbpf.h btf.h libbpf_common.h libbpf_legacy.h xsk.h \
-		  bpf_helpers.h $(BPF_HELPER_DEFS) bpf_tracing.h	     \
-		  bpf_endian.h bpf_core_read.h skel_internal.h
+		  bpf_helpers.h $(BPF_GENERATED) bpf_tracing.h		     \
+		  bpf_endian.h bpf_core_read.h skel_internal.h		     \
+		  libbpf_version.h
 
-install_headers: $(BPF_HELPER_DEFS)
+install_headers: $(BPF_GENERATED)
 	$(call QUIET_INSTALL, headers)					     \
 		$(foreach hdr,$(INSTALL_HEADERS),			     \
 			$(call do_install,$(hdr),$(prefix)/include/bpf,644);)
···
 
 clean:
 	$(call QUIET_CLEAN, libbpf) $(RM) -rf $(CMD_TARGETS)		     \
-		*~ .*.d .*.cmd LIBBPF-CFLAGS $(BPF_HELPER_DEFS)		     \
+		*~ .*.d .*.cmd LIBBPF-CFLAGS $(BPF_GENERATED)		     \
 		$(SHARED_OBJDIR) $(STATIC_OBJDIR)			     \
 		$(addprefix $(OUTPUT),					     \
 			    *.o *.a *.so *.so.$(LIBBPF_MAJOR_VERSION) *.pc)
 
-PHONY += force cscope tags
+PHONY += force cscope tags check check_abi check_version
 force:
 
 cscope:

tools/lib/bpf/btf.c

···
 		return base_size + sizeof(struct btf_var);
 	case BTF_KIND_DATASEC:
 		return base_size + vlen * sizeof(struct btf_var_secinfo);
+	case BTF_KIND_TAG:
+		return base_size + sizeof(struct btf_tag);
 	default:
 		pr_debug("Unsupported BTF_KIND:%u\n", btf_kind(t));
 		return -EINVAL;
···
 			v->offset = bswap_32(v->offset);
 			v->size = bswap_32(v->size);
 		}
+		return 0;
+	case BTF_KIND_TAG:
+		btf_tag(t)->component_idx = bswap_32(btf_tag(t)->component_idx);
 		return 0;
 	default:
 		pr_debug("Unsupported BTF_KIND:%u\n", btf_kind(t));
···
 		case BTF_KIND_CONST:
 		case BTF_KIND_RESTRICT:
 		case BTF_KIND_VAR:
+		case BTF_KIND_TAG:
 			type_id = t->type;
 			break;
 		case BTF_KIND_ARRAY:
···
 	return 0;
 }
 
+/*
+ * Append new BTF_KIND_TAG type with:
+ *   - *value* - non-empty/non-NULL string;
+ *   - *ref_type_id* - referenced type ID, it might not exist yet;
+ *   - *component_idx* - -1 for tagging reference type, otherwise struct/union
+ *     member or function argument index;
+ * Returns:
+ *   - >0, type ID of newly added BTF type;
+ *   - <0, on error.
+ */
+int btf__add_tag(struct btf *btf, const char *value, int ref_type_id,
+		 int component_idx)
+{
+	struct btf_type *t;
+	int sz, value_off;
+
+	if (!value || !value[0] || component_idx < -1)
+		return libbpf_err(-EINVAL);
+
+	if (validate_type_id(ref_type_id))
+		return libbpf_err(-EINVAL);
+
+	if (btf_ensure_modifiable(btf))
+		return libbpf_err(-ENOMEM);
+
+	sz = sizeof(struct btf_type) + sizeof(struct btf_tag);
+	t = btf_add_type_mem(btf, sz);
+	if (!t)
+		return libbpf_err(-ENOMEM);
+
+	value_off = btf__add_str(btf, value);
+	if (value_off < 0)
+		return value_off;
+
+	t->name_off = value_off;
+	t->info = btf_type_info(BTF_KIND_TAG, 0, false);
+	t->type = ref_type_id;
+	btf_tag(t)->component_idx = component_idx;
+
+	return btf_commit_type(btf, sz);
+}
+
 struct btf_ext_sec_setup_param {
 	__u32 off;
 	__u32 len;
···
 	       t1->size == t2->size;
 }
 
-/* Calculate type signature hash of INT. */
-static long btf_hash_int(struct btf_type *t)
+/* Calculate type signature hash of INT or TAG. */
+static long btf_hash_int_tag(struct btf_type *t)
 {
 	__u32 info = *(__u32 *)(t + 1);
 	long h;
···
 	return h;
 }
 
-/* Check structural equality of two INTs. */
-static bool btf_equal_int(struct btf_type *t1, struct btf_type *t2)
+/* Check structural equality of two INTs or TAGs. */
+static bool btf_equal_int_tag(struct btf_type *t1, struct btf_type *t2)
 {
 	__u32 info1, info2;
 
···
 			h = btf_hash_common(t);
 			break;
 		case BTF_KIND_INT:
-			h = btf_hash_int(t);
+		case BTF_KIND_TAG:
+			h = btf_hash_int_tag(t);
 			break;
 		case BTF_KIND_ENUM:
 			h = btf_hash_enum(t);
···
 	case BTF_KIND_FUNC_PROTO:
 	case BTF_KIND_VAR:
 	case BTF_KIND_DATASEC:
+	case BTF_KIND_TAG:
 		return 0;
 
 	case BTF_KIND_INT:
-		h = btf_hash_int(t);
+		h = btf_hash_int_tag(t);
 		for_each_dedup_cand(d, hash_entry, h) {
 			cand_id = (__u32)(long)hash_entry->value;
 			cand = btf_type_by_id(d->btf, cand_id);
-			if (btf_equal_int(t, cand)) {
+			if (btf_equal_int_tag(t, cand)) {
 				new_id = cand_id;
 				break;
 			}
···
 
 	switch (cand_kind) {
 	case BTF_KIND_INT:
-		return btf_equal_int(cand_type, canon_type);
+		return btf_equal_int_tag(cand_type, canon_type);
 
 	case BTF_KIND_ENUM:
 		if (d->opts.dont_resolve_fwds)
···
 		}
 		break;
 
+	case BTF_KIND_TAG:
+		ref_type_id = btf_dedup_ref_type(d, t->type);
+		if (ref_type_id < 0)
+			return ref_type_id;
+		t->type = ref_type_id;
+
+		h = btf_hash_int_tag(t);
+		for_each_dedup_cand(d, hash_entry, h) {
+			cand_id = (__u32)(long)hash_entry->value;
+			cand = btf_type_by_id(d->btf, cand_id);
+			if (btf_equal_int_tag(t, cand)) {
+				new_id = cand_id;
+				break;
+			}
+		}
+		break;
+
 	case BTF_KIND_ARRAY: {
 		struct btf_array *info = btf_array(t);
 
···
 	case BTF_KIND_TYPEDEF:
 	case BTF_KIND_FUNC:
 	case BTF_KIND_VAR:
+	case BTF_KIND_TAG:
 		return visit(&t->type, ctx);
 
 	case BTF_KIND_ARRAY: {

tools/lib/bpf/btf.h

···
 /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
 /* Copyright (c) 2018 Facebook */
+/*! \file */
 
 #ifndef __LIBBPF_BTF_H
 #define __LIBBPF_BTF_H
···
 	BTF_BIG_ENDIAN = 1,
 };
 
+/**
+ * @brief **btf__free()** frees all data of a BTF object
+ * @param btf BTF object to free
+ */
 LIBBPF_API void btf__free(struct btf *btf);
 
+/**
+ * @brief **btf__new()** creates a new instance of a BTF object from the raw
+ * bytes of an ELF's BTF section
+ * @param data raw bytes
+ * @param size number of bytes passed in `data`
+ * @return new BTF object instance which has to be eventually freed with
+ * **btf__free()**
+ *
+ * On error, error-code-encoded-as-pointer is returned, not a NULL. To extract
+ * error code from such a pointer `libbpf_get_error()` should be used. If
+ * `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)` is enabled, NULL is
+ * returned on error instead. In both cases thread-local `errno` variable is
+ * always set to error code as well.
+ */
 LIBBPF_API struct btf *btf__new(const void *data, __u32 size);
+
+/**
+ * @brief **btf__new_split()** create a new instance of a BTF object from the
+ * provided raw data bytes. It takes another BTF instance, **base_btf**, which
+ * serves as a base BTF, which is extended by types in a newly created BTF
+ * instance
+ * @param data raw bytes
+ * @param size length of raw bytes
+ * @param base_btf the base BTF object
+ * @return new BTF object instance which has to be eventually freed with
+ * **btf__free()**
+ *
+ * If *base_btf* is NULL, `btf__new_split()` is equivalent to `btf__new()` and
+ * creates non-split BTF.
+ *
+ * On error, error-code-encoded-as-pointer is returned, not a NULL. To extract
+ * error code from such a pointer `libbpf_get_error()` should be used. If
+ * `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)` is enabled, NULL is
+ * returned on error instead. In both cases thread-local `errno` variable is
+ * always set to error code as well.
+ */
 LIBBPF_API struct btf *btf__new_split(const void *data, __u32 size, struct btf *base_btf);
+
+/**
+ * @brief **btf__new_empty()** creates an empty BTF object.  Use
+ * `btf__add_*()` to populate such BTF object.
+ * @return new BTF object instance which has to be eventually freed with
+ * **btf__free()**
+ *
+ * On error, error-code-encoded-as-pointer is returned, not a NULL. To extract
+ * error code from such a pointer `libbpf_get_error()` should be used. If
+ * `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)` is enabled, NULL is
+ * returned on error instead. In both cases thread-local `errno` variable is
+ * always set to error code as well.
+ */
 LIBBPF_API struct btf *btf__new_empty(void);
+
+/**
+ * @brief **btf__new_empty_split()** creates an unpopulated BTF object from an
+ * ELF BTF section except with a base BTF on top of which split BTF should be
+ * based
+ * @return new BTF object instance which has to be eventually freed with
+ * **btf__free()**
+ *
+ * If *base_btf* is NULL, `btf__new_empty_split()` is equivalent to
+ * `btf__new_empty()` and creates non-split BTF.
+ *
+ * On error, error-code-encoded-as-pointer is returned, not a NULL. To extract
+ * error code from such a pointer `libbpf_get_error()` should be used. If
+ * `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)` is enabled, NULL is
+ * returned on error instead. In both cases thread-local `errno` variable is
+ * always set to error code as well.
+ */
 LIBBPF_API struct btf *btf__new_empty_split(struct btf *base_btf);
 
 LIBBPF_API struct btf *btf__parse(const char *path, struct btf_ext **btf_ext);
···
 
 LIBBPF_API struct btf *btf__load_from_kernel_by_id(__u32 id);
 LIBBPF_API struct btf *btf__load_from_kernel_by_id_split(__u32 id, struct btf *base_btf);
+LIBBPF_DEPRECATED_SINCE(0, 6, "use btf__load_from_kernel_by_id instead")
 LIBBPF_API int btf__get_from_id(__u32 id, struct btf **btf);
 
 LIBBPF_API int btf__finalize_data(struct bpf_object *obj, struct btf *btf);
+LIBBPF_DEPRECATED_SINCE(0, 6, "use btf__load_into_kernel instead")
 LIBBPF_API int btf__load(struct btf *btf);
 LIBBPF_API int btf__load_into_kernel(struct btf *btf);
 LIBBPF_API __s32 btf__find_by_name(const struct btf *btf,
···
 LIBBPF_API int btf__add_datasec(struct btf *btf, const char *name, __u32 byte_sz);
 LIBBPF_API int btf__add_datasec_var_info(struct btf *btf, int var_type_id,
 					 __u32 offset, __u32 byte_sz);
+
+/* tag construction API */
+LIBBPF_API int btf__add_tag(struct btf *btf, const char *value, int ref_type_id,
+			    int component_idx);
 
 struct btf_dedup_opts {
 	unsigned int dedup_table_size;
···
 	return btf_kind(t) == BTF_KIND_FLOAT;
 }
 
+static inline bool btf_is_tag(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_TAG;
+}
+
 static inline __u8 btf_int_encoding(const struct btf_type *t)
 {
 	return BTF_INT_ENCODING(*(__u32 *)(t + 1));
···
 btf_var_secinfos(const struct btf_type *t)
 {
 	return (struct btf_var_secinfo *)(t + 1);
+}
+
+struct btf_tag;
+static inline struct btf_tag *btf_tag(const struct btf_type *t)
+{
+	return (struct btf_tag *)(t + 1);
 }
 
 #ifdef __cplusplus

tools/lib/bpf/btf_dump.c

···
 		case BTF_KIND_TYPEDEF:
 		case BTF_KIND_FUNC:
 		case BTF_KIND_VAR:
+		case BTF_KIND_TAG:
 			d->type_states[t->type].referenced = 1;
 			break;
 
···
 	case BTF_KIND_FUNC:
 	case BTF_KIND_VAR:
 	case BTF_KIND_DATASEC:
+	case BTF_KIND_TAG:
 		d->type_states[id].order_state = ORDERED;
 		return 0;
 
···
 	case BTF_KIND_FWD:
 	case BTF_KIND_FUNC:
 	case BTF_KIND_FUNC_PROTO:
+	case BTF_KIND_TAG:
 		err = btf_dump_unsupported_data(d, t, id);
 		break;
 	case BTF_KIND_INT:

tools/lib/bpf/libbpf.c

···
 	FEAT_BTF_FLOAT,
 	/* BPF perf link support */
 	FEAT_PERF_LINK,
+	/* BTF_KIND_TAG support */
+	FEAT_BTF_TAG,
 	__FEAT_CNT,
 };
 
···
 
 struct bpf_sec_def;
 
-typedef struct bpf_link *(*attach_fn_t)(const struct bpf_sec_def *sec,
-					struct bpf_program *prog);
+typedef struct bpf_link *(*attach_fn_t)(const struct bpf_program *prog);
 
 struct bpf_sec_def {
 	const char *sec;
···
 	case BTF_KIND_VAR: return "var";
 	case BTF_KIND_DATASEC: return "datasec";
 	case BTF_KIND_FLOAT: return "float";
+	case BTF_KIND_TAG: return "tag";
 	default: return "unknown";
 	}
 }
···
 	bool has_datasec = kernel_supports(obj, FEAT_BTF_DATASEC);
 	bool has_float = kernel_supports(obj, FEAT_BTF_FLOAT);
 	bool has_func = kernel_supports(obj, FEAT_BTF_FUNC);
+	bool has_tag = kernel_supports(obj, FEAT_BTF_TAG);
 
-	return !has_func || !has_datasec || !has_func_global || !has_float;
+	return !has_func || !has_datasec || !has_func_global || !has_float || !has_tag;
 }
 
 static void bpf_object__sanitize_btf(struct bpf_object *obj, struct btf *btf)
···
 	bool has_datasec = kernel_supports(obj, FEAT_BTF_DATASEC);
 	bool has_float = kernel_supports(obj, FEAT_BTF_FLOAT);
 	bool has_func = kernel_supports(obj, FEAT_BTF_FUNC);
+	bool has_tag = kernel_supports(obj, FEAT_BTF_TAG);
 	struct btf_type *t;
 	int i, j, vlen;
 
 	for (i = 1; i <= btf__get_nr_types(btf); i++) {
 		t = (struct btf_type *)btf__type_by_id(btf, i);
 
-		if (!has_datasec && btf_is_var(t)) {
-			/* replace VAR with INT */
+		if ((!has_datasec && btf_is_var(t)) || (!has_tag && btf_is_tag(t))) {
+			/* replace VAR/TAG with INT */
 			t->info = BTF_INFO_ENC(BTF_KIND_INT, 0, 0);
 			/*
 			 * using size = 1 is the safest choice, 4 will be too
···
 			obj->efile.symbols_shndx = elf_ndxscn(scn);
 			obj->efile.strtabidx = sh.sh_link;
 		}
+	}
+
+	if (!obj->efile.symbols) {
+		pr_warn("elf: couldn't find symbol table in %s, stripped object file?\n",
+			obj->path);
+		return -ENOENT;
 	}
 
 	scn = NULL;
···
 					     strs, sizeof(strs)));
 }
 
+static int probe_kern_btf_tag(void)
+{
+	static const char strs[] = "\0tag";
+	__u32 types[] = {
+		/* int */
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),  /* [1] */
+		/* VAR x */                                     /* [2] */
+		BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_VAR, 0, 0), 1),
+		BTF_VAR_STATIC,
+		/* attr */
+		BTF_TYPE_TAG_ENC(1, 2, -1),
+	};
+
+	return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types),
+					     strs, sizeof(strs)));
+}
+
 static int probe_kern_array_mmap(void)
 {
 	struct bpf_create_map_attr attr = {
···
 	},
 	[FEAT_PERF_LINK] = {
 		"BPF perf link support", probe_perf_link,
+	},
+	[FEAT_BTF_TAG] = {
+		"BTF_KIND_TAG support", probe_kern_btf_tag,
 	},
 };
 
···
 
 static const struct bpf_sec_def *find_sec_def(const char *sec_name);
 
+static int bpf_object_init_progs(struct bpf_object *obj, const struct bpf_object_open_opts *opts)
+{
+	struct bpf_program *prog;
+
+	bpf_object__for_each_program(prog, obj) {
+		prog->sec_def = find_sec_def(prog->sec_name);
+		if (!prog->sec_def) {
+			/* couldn't guess, but user might manually specify */
+			pr_debug("prog '%s': unrecognized ELF section name '%s'\n",
+				prog->name, prog->sec_name);
+			continue;
+		}
+
+		if (prog->sec_def->is_sleepable)
+			prog->prog_flags |= BPF_F_SLEEPABLE;
+		bpf_program__set_type(prog, prog->sec_def->prog_type);
+		bpf_program__set_expected_attach_type(prog, prog->sec_def->expected_attach_type);
+
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+		if (prog->sec_def->prog_type == BPF_PROG_TYPE_TRACING ||
+		    prog->sec_def->prog_type == BPF_PROG_TYPE_EXT)
+			prog->attach_prog_fd = OPTS_GET(opts, attach_prog_fd, 0);
+#pragma GCC diagnostic pop
+	}
+
+	return 0;
+}
+
 static struct bpf_object *
 __bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz,
 		   const struct bpf_object_open_opts *opts)
 {
 	const char *obj_name, *kconfig, *btf_tmp_path;
-	struct bpf_program *prog;
 	struct bpf_object *obj;
 	char tmp_name[64];
 	int err;
···
 	err = err ? : bpf_object__collect_externs(obj);
 	err = err ? : bpf_object__finalize_btf(obj);
 	err = err ? : bpf_object__init_maps(obj, opts);
+	err = err ? : bpf_object_init_progs(obj, opts);
 	err = err ? : bpf_object__collect_relos(obj);
 	if (err)
 		goto out;
+
 	bpf_object__elf_finish(obj);
-
-	bpf_object__for_each_program(prog, obj) {
-		prog->sec_def = find_sec_def(prog->sec_name);
-		if (!prog->sec_def) {
-			/* couldn't guess, but user might manually specify */
-			pr_debug("prog '%s': unrecognized ELF section name '%s'\n",
-				prog->name, prog->sec_name);
-			continue;
-		}
-
-		if (prog->sec_def->is_sleepable)
-			prog->prog_flags |= BPF_F_SLEEPABLE;
-		bpf_program__set_type(prog, prog->sec_def->prog_type);
-		bpf_program__set_expected_attach_type(prog,
-				prog->sec_def->expected_attach_type);
-
-		if (prog->sec_def->prog_type == BPF_PROG_TYPE_TRACING ||
-		    prog->sec_def->prog_type == BPF_PROG_TYPE_EXT)
-			prog->attach_prog_fd = OPTS_GET(opts, attach_prog_fd, 0);
-	}
 
 	return obj;
 out:
···
 	__VA_ARGS__							    \
 }
 
-static struct bpf_link *attach_kprobe(const struct bpf_sec_def *sec,
-				      struct bpf_program *prog);
-static struct bpf_link *attach_tp(const struct bpf_sec_def *sec,
-				  struct bpf_program *prog);
-static struct bpf_link *attach_raw_tp(const struct bpf_sec_def *sec,
-				      struct bpf_program *prog);
-static struct bpf_link *attach_trace(const struct bpf_sec_def *sec,
-				     struct bpf_program *prog);
-static struct bpf_link *attach_lsm(const struct bpf_sec_def *sec,
-				   struct bpf_program *prog);
-static struct bpf_link *attach_iter(const struct bpf_sec_def *sec,
-				    struct bpf_program *prog);
+static struct bpf_link *attach_kprobe(const struct bpf_program *prog);
+static struct bpf_link *attach_tp(const struct bpf_program *prog);
+static struct bpf_link *attach_raw_tp(const struct bpf_program *prog);
+static struct bpf_link *attach_trace(const struct bpf_program *prog);
+static struct bpf_link *attach_lsm(const struct bpf_program *prog);
+static struct bpf_link *attach_iter(const struct bpf_program *prog);
 
 static const struct bpf_sec_def section_defs[] = {
 	BPF_PROG_SEC("socket",			BPF_PROG_TYPE_SOCKET_FILTER),
···
 			return -EINVAL;
 		}
 
-		if (prog->type == BPF_PROG_TYPE_UNSPEC) {
-			const struct bpf_sec_def *sec_def;
+		/* prevent the use of BPF prog with invalid type */
+		if (prog->type != BPF_PROG_TYPE_STRUCT_OPS) {
+			pr_warn("struct_ops reloc %s: prog %s is not struct_ops BPF program\n",
+				map->name, prog->name);
+			return -EINVAL;
+		}
 
-			sec_def = find_sec_def(prog->sec_name);
-			if (sec_def &&
-			    sec_def->prog_type != BPF_PROG_TYPE_STRUCT_OPS) {
-				/* for pr_warn */
-				prog->type = sec_def->prog_type;
-				goto invalid_prog;
-			}
-
-			prog->type = BPF_PROG_TYPE_STRUCT_OPS;
+		/* if we haven't yet processed this BPF program, record proper
+		 * attach_btf_id and member_idx
+		 */
+		if (!prog->attach_btf_id) {
 			prog->attach_btf_id = st_ops->type_id;
 			prog->expected_attach_type = member_idx;
-		} else if (prog->type != BPF_PROG_TYPE_STRUCT_OPS ||
-			   prog->attach_btf_id != st_ops->type_id ||
-			   prog->expected_attach_type != member_idx) {
-			goto invalid_prog;
 		}
+
+		/* struct_ops BPF prog can be re-used between multiple
+		 * .struct_ops as long as it's the same struct_ops struct
+		 * definition and the same function pointer field
+		 */
+		if (prog->attach_btf_id != st_ops->type_id ||
+		    prog->expected_attach_type != member_idx) {
+			pr_warn("struct_ops reloc %s: cannot use prog %s in sec %s with type %u attach_btf_id %u expected_attach_type %u for func ptr %s\n",
+				map->name, prog->name, prog->sec_name, prog->type,
+				prog->attach_btf_id, prog->expected_attach_type, name);
+			return -EINVAL;
+		}
+
 		st_ops->progs[member_idx] = prog;
 	}
 
 	return 0;
-
-invalid_prog:
-	pr_warn("struct_ops reloc %s: cannot use prog %s in sec %s with type %u attach_btf_id %u expected_attach_type %u for func ptr %s\n",
-		map->name, prog->name, prog->sec_name, prog->type,
-		prog->attach_btf_id, prog->expected_attach_type, name);
-	return -EINVAL;
 }
 
 #define BTF_TRACE_PREFIX "btf_trace_"
···
 {
 	enum bpf_attach_type attach_type = prog->expected_attach_type;
 	__u32 attach_prog_fd = prog->attach_prog_fd;
-	const char *name = prog->sec_name, *attach_name;
-	const struct bpf_sec_def *sec = NULL;
-	int i, err = 0;
+	const char *attach_name;
+	int err = 0;
 
-	if (!name)
-		return -EINVAL;
-
-	for (i = 0; i < ARRAY_SIZE(section_defs); i++) {
-		if (!section_defs[i].is_attach_btf)
-			continue;
-		if (strncmp(name, section_defs[i].sec, section_defs[i].len))
-			continue;
-
-		sec = &section_defs[i];
-		break;
-	}
-
-	if (!sec) {
-		pr_warn("failed to identify BTF ID based on ELF section name '%s'\n", name);
+	if (!prog->sec_def || !prog->sec_def->is_attach_btf) {
+		pr_warn("failed to identify BTF ID based on ELF section name '%s'\n",
+			prog->sec_name);
 		return -ESRCH;
 	}
-	attach_name = name + sec->len;
+	attach_name = prog->sec_name + prog->sec_def->len;
 
 	/* BPF program's BTF ID */
 	if (attach_prog_fd) {
···
 			       enum bpf_attach_type *attach_type)
 {
 	char *type_names;
-	int i;
+	const struct bpf_sec_def *sec_def;
 
 	if (!name)
 		return libbpf_err(-EINVAL);
 
-	for (i = 0; i < ARRAY_SIZE(section_defs); i++) {
-		if (strncmp(name, section_defs[i].sec, section_defs[i].len))
-			continue;
-		if (!section_defs[i].is_attachable)
-			return libbpf_err(-EINVAL);
-		*attach_type = section_defs[i].expected_attach_type;
-		return 0;
-	}
-	pr_debug("failed to guess attach type based on ELF section name '%s'\n", name);
-	type_names = libbpf_get_type_names(true);
-	if (type_names != NULL) {
-		pr_debug("attachable section(type) names are:%s\n", type_names);
-		free(type_names);
+	sec_def = find_sec_def(name);
+	if (!sec_def) {
+		pr_debug("failed to guess attach type based on ELF section name '%s'\n", name);
+		type_names = libbpf_get_type_names(true);
+		if (type_names != NULL) {
+			pr_debug("attachable section(type) names are:%s\n", type_names);
+			free(type_names);
+		}
+
+		return libbpf_err(-EINVAL);
 	}
 
-	return libbpf_err(-EINVAL);
+	if (!sec_def->is_attachable)
+		return libbpf_err(-EINVAL);
+
+	*attach_type = sec_def->expected_attach_type;
+	return 0;
 }
 
 int bpf_map__fd(const struct bpf_map *map)
···
 	return 0;
 }
 
+static int poke_kprobe_events(bool add, const char *name, bool retprobe, uint64_t offset)
+{
+	int fd, ret = 0;
+	pid_t p = getpid();
+	char cmd[260], probename[128], probefunc[128];
+	const char *file = "/sys/kernel/debug/tracing/kprobe_events";
+
+	if (retprobe)
+		snprintf(probename, sizeof(probename), "kretprobes/%s_libbpf_%u", name, p);
+	else
+		snprintf(probename, sizeof(probename), "kprobes/%s_libbpf_%u", name, p);
+
+	if (offset)
+		snprintf(probefunc, sizeof(probefunc), "%s+%zu", name, (size_t)offset);
+
+	if (add) {
+		snprintf(cmd, sizeof(cmd), "%c:%s %s",
+			 retprobe ? 'r' : 'p',
+			 probename,
+			 offset ? probefunc : name);
+	} else {
+		snprintf(cmd, sizeof(cmd), "-:%s", probename);
+	}
+
+	fd = open(file, O_WRONLY | O_APPEND, 0);
+	if (!fd)
+		return -errno;
+	ret = write(fd, cmd, strlen(cmd));
+	if (ret < 0)
+		ret = -errno;
+	close(fd);
+
+	return ret;
+}
+
+static inline int add_kprobe_event_legacy(const char *name, bool retprobe, uint64_t offset)
+{
+	return poke_kprobe_events(true, name, retprobe, offset);
+}
+
+static inline int remove_kprobe_event_legacy(const char *name, bool retprobe)
+{
+	return poke_kprobe_events(false, name, retprobe, 0);
+}
+
 struct bpf_link_perf {
 	struct bpf_link link;
 	int perf_event_fd;
+	/* legacy kprobe support: keep track of probe identifier and type */
+	char *legacy_probe_name;
+	bool legacy_is_retprobe;
 };
 
 static int bpf_link_perf_detach(struct bpf_link *link)
···
 		close(perf_link->perf_event_fd);
 	close(link->fd);
 
-	return libbpf_err(err);
+	/* legacy kprobe needs to be removed after perf event fd closure */
+	if (perf_link->legacy_probe_name)
+		err = remove_kprobe_event_legacy(perf_link->legacy_probe_name,
+						 perf_link->legacy_is_retprobe);
+
+	return err;
 }
 
 static void bpf_link_perf_dealloc(struct bpf_link *link)
 {
 	struct bpf_link_perf *perf_link = container_of(link, struct bpf_link_perf, link);
 
+	free(perf_link->legacy_probe_name);
 	free(perf_link);
 }
 
-struct bpf_link *bpf_program__attach_perf_event_opts(struct bpf_program *prog, int pfd,
+struct bpf_link *bpf_program__attach_perf_event_opts(const struct bpf_program *prog, int pfd,
 						     const struct bpf_perf_event_opts *opts)
 {
 	char errmsg[STRERR_BUFSIZE];
···
 	return libbpf_err_ptr(err);
 }
 
-struct bpf_link *bpf_program__attach_perf_event(struct bpf_program *prog, int pfd)
+struct bpf_link *bpf_program__attach_perf_event(const struct bpf_program *prog, int pfd)
 {
 	return bpf_program__attach_perf_event_opts(prog, pfd, NULL);
 }
···
 	}
 	fclose(f);
 	return ret;
+}
+
+static int determine_kprobe_perf_type_legacy(const char *func_name, bool is_retprobe)
+{
+	char file[192];
+
+	snprintf(file, sizeof(file),
+		 "/sys/kernel/debug/tracing/events/%s/%s_libbpf_%d/id",
+		 is_retprobe ? "kretprobes" : "kprobes",
+		 func_name, getpid());
+
+	return parse_uint_from_file(file, "%d\n");
 }
 
 static int determine_kprobe_perf_type(void)
···
 	return pfd;
 }
 
+static int perf_event_kprobe_open_legacy(bool retprobe, const char *name, uint64_t offset, int pid)
+{
+	struct perf_event_attr attr = {};
+	char errmsg[STRERR_BUFSIZE];
+	int type, pfd, err;
+
+	err = add_kprobe_event_legacy(name, retprobe, offset);
+	if (err < 0) {
+		pr_warn("failed to add legacy kprobe event: %s\n",
+			libbpf_strerror_r(err, errmsg, sizeof(errmsg)));
+		return err;
+	}
+	type = determine_kprobe_perf_type_legacy(name, retprobe);
+	if (type < 0) {
+		pr_warn("failed to determine legacy kprobe event id: %s\n",
+			libbpf_strerror_r(type, errmsg, sizeof(errmsg)));
+		return type;
+	}
+	attr.size = sizeof(attr);
+	attr.config = type;
+	attr.type = PERF_TYPE_TRACEPOINT;
+
+	pfd = syscall(__NR_perf_event_open, &attr,
+		      pid < 0 ? -1 : pid, /* pid */
+		      pid == -1 ? 0 : -1, /* cpu */
+		      -1 /* group_fd */,  PERF_FLAG_FD_CLOEXEC);
+	if (pfd < 0) {
+		err = -errno;
+		pr_warn("legacy kprobe perf_event_open() failed: %s\n",
+			libbpf_strerror_r(err, errmsg, sizeof(errmsg)));
+		return err;
+	}
+	return pfd;
+}
+
 struct bpf_link *
-bpf_program__attach_kprobe_opts(struct bpf_program *prog,
+bpf_program__attach_kprobe_opts(const struct bpf_program *prog,
 				const char *func_name,
 				const struct bpf_kprobe_opts *opts)
 {
 	DECLARE_LIBBPF_OPTS(bpf_perf_event_opts, pe_opts);
 	char errmsg[STRERR_BUFSIZE];
+	char *legacy_probe = NULL;
 	struct bpf_link *link;
 	unsigned long offset;
-	bool retprobe;
+	bool retprobe, legacy;
 	int pfd, err;
 
 	if (!OPTS_VALID(opts, bpf_kprobe_opts))
···
 	offset = OPTS_GET(opts, offset, 0);
 	pe_opts.bpf_cookie = OPTS_GET(opts, bpf_cookie, 0);
 
-	pfd = perf_event_open_probe(false /* uprobe */, retprobe, func_name,
-				    offset, -1 /* pid */, 0 /* ref_ctr_off */);
+	legacy = determine_kprobe_perf_type() < 0;
+	if (!legacy) {
+		pfd = perf_event_open_probe(false /* uprobe */, retprobe,
+					    func_name, offset,
+					    -1 /* pid */, 0 /* ref_ctr_off */);
+	} else {
+		legacy_probe = strdup(func_name);
+		if (!legacy_probe)
+			return libbpf_err_ptr(-ENOMEM);
+
+		pfd = perf_event_kprobe_open_legacy(retprobe, func_name,
+						    offset, -1 /* pid */);
+	}
 	if (pfd < 0) {
 		pr_warn("prog '%s': failed to create %s '%s' perf event: %s\n",
 			prog->name, retprobe ? "kretprobe" : "kprobe", func_name,
···
 			libbpf_strerror_r(err, errmsg, sizeof(errmsg)));
 		return libbpf_err_ptr(err);
 	}
+	if (legacy) {
+		struct bpf_link_perf *perf_link = container_of(link, struct bpf_link_perf, link);
+
+		perf_link->legacy_probe_name = legacy_probe;
+		perf_link->legacy_is_retprobe = retprobe;
+	}
+
 	return link;
 }
 
-struct bpf_link *bpf_program__attach_kprobe(struct bpf_program *prog,
+struct bpf_link *bpf_program__attach_kprobe(const struct bpf_program *prog,
 					    bool retprobe,
 					    const char *func_name)
 {
···
 	return bpf_program__attach_kprobe_opts(prog, func_name, &opts);
 }
 
-static struct bpf_link *attach_kprobe(const struct bpf_sec_def *sec,
-				      struct bpf_program *prog)
+static struct bpf_link *attach_kprobe(const struct bpf_program *prog)
 {
 	DECLARE_LIBBPF_OPTS(bpf_kprobe_opts, opts);
 	unsigned long offset = 0;
···
 	char *func;
 	int n, err;
 
-	func_name = prog->sec_name + sec->len;
-	opts.retprobe = strcmp(sec->sec, "kretprobe/") == 0;
+	func_name = prog->sec_name + prog->sec_def->len;
+	opts.retprobe = strcmp(prog->sec_def->sec, "kretprobe/") == 0;
 
 	n = sscanf(func_name, "%m[a-zA-Z0-9_.]+%li", &func, &offset);
 	if (n < 1) {
···
 }
 
 LIBBPF_API struct bpf_link *
-bpf_program__attach_uprobe_opts(struct bpf_program *prog, pid_t pid,
+bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid,
 				const char *binary_path, size_t func_offset,
 				const struct bpf_uprobe_opts *opts)
 {
···
 	return link;
 }
 
-struct bpf_link *bpf_program__attach_uprobe(struct bpf_program *prog,
+struct bpf_link *bpf_program__attach_uprobe(const struct bpf_program *prog,
 					    bool retprobe, pid_t pid,
 					    const char *binary_path,
 					    size_t func_offset)
···
 	return pfd;
 }
 
-struct bpf_link *bpf_program__attach_tracepoint_opts(struct bpf_program *prog,
+struct bpf_link *bpf_program__attach_tracepoint_opts(const struct bpf_program *prog,
 						     const char *tp_category,
 						     const char *tp_name,
 						     const struct bpf_tracepoint_opts *opts)
···
 	return link;
 }
 
-struct bpf_link *bpf_program__attach_tracepoint(struct bpf_program *prog,
+struct bpf_link *bpf_program__attach_tracepoint(const struct bpf_program *prog,
 						const char *tp_category,
 						const char *tp_name)
 {
 	return bpf_program__attach_tracepoint_opts(prog, tp_category, tp_name, NULL);
 }
 
-static struct bpf_link *attach_tp(const struct bpf_sec_def *sec,
-				  struct bpf_program *prog)
+static struct bpf_link *attach_tp(const struct bpf_program *prog)
 {
 	char *sec_name, *tp_cat, *tp_name;
 	struct bpf_link *link;
···
 		return libbpf_err_ptr(-ENOMEM);
 
 	/* extract "tp/<category>/<name>" */
-	tp_cat = sec_name + sec->len;
+	tp_cat = sec_name + prog->sec_def->len;
 	tp_name = strchr(tp_cat, '/');
 	if (!tp_name) {
 		free(sec_name);
···
 	return link;
 }
 
-struct bpf_link *bpf_program__attach_raw_tracepoint(struct bpf_program *prog,
+struct bpf_link *bpf_program__attach_raw_tracepoint(const struct bpf_program *prog,
 						    const char *tp_name)
 {
 	char errmsg[STRERR_BUFSIZE];
···
 	return link;
 }
 
-static struct bpf_link *attach_raw_tp(const struct bpf_sec_def *sec,
-				      struct bpf_program *prog)
+static struct bpf_link *attach_raw_tp(const struct bpf_program *prog)
 {
-	const char *tp_name = prog->sec_name + sec->len;
+	const char *tp_name = prog->sec_name + prog->sec_def->len;
 
 	return bpf_program__attach_raw_tracepoint(prog, tp_name);
 }
 
 /* Common logic for all BPF program types that attach to a btf_id */
-static struct bpf_link *bpf_program__attach_btf_id(struct bpf_program *prog)
+static struct bpf_link *bpf_program__attach_btf_id(const struct bpf_program *prog)
 {
 	char errmsg[STRERR_BUFSIZE];
 	struct bpf_link *link;
···
 	return (struct bpf_link *)link;
 }
 
-struct bpf_link *bpf_program__attach_trace(struct bpf_program *prog)
+struct bpf_link *bpf_program__attach_trace(const struct bpf_program *prog)
 {
 	return bpf_program__attach_btf_id(prog);
 }
 
-struct bpf_link *bpf_program__attach_lsm(struct bpf_program *prog)
+struct bpf_link *bpf_program__attach_lsm(const struct bpf_program *prog)
 {
 	return bpf_program__attach_btf_id(prog);
 }
 
-static struct bpf_link *attach_trace(const struct bpf_sec_def *sec,
-				     struct bpf_program *prog)
+static struct bpf_link *attach_trace(const struct bpf_program *prog)
 {
 	return bpf_program__attach_trace(prog);
 }
 
-static struct bpf_link *attach_lsm(const struct bpf_sec_def *sec,
-				   struct bpf_program *prog)
+static struct bpf_link *attach_lsm(const struct bpf_program *prog)
 {
 	return bpf_program__attach_lsm(prog);
 }
 
 static struct bpf_link *
-bpf_program__attach_fd(struct bpf_program *prog, int target_fd, int btf_id,
+bpf_program__attach_fd(const struct bpf_program *prog, int target_fd, int btf_id,
 		       const char *target_name)
 {
 	DECLARE_LIBBPF_OPTS(bpf_link_create_opts, opts,
···
 }
 
 struct bpf_link *
-bpf_program__attach_cgroup(struct bpf_program *prog, int cgroup_fd)
+bpf_program__attach_cgroup(const struct bpf_program *prog, int cgroup_fd)
 {
 	return bpf_program__attach_fd(prog, cgroup_fd, 0, "cgroup");
 }
 
 struct bpf_link *
-bpf_program__attach_netns(struct bpf_program *prog, int netns_fd)
+bpf_program__attach_netns(const struct bpf_program *prog, int netns_fd)
 {
 	return bpf_program__attach_fd(prog, netns_fd, 0, "netns");
 }
 
-struct bpf_link *bpf_program__attach_xdp(struct bpf_program *prog, int ifindex)
+struct bpf_link *bpf_program__attach_xdp(const struct bpf_program *prog, int ifindex)
 {
 	/* target_fd/target_ifindex use the same field in LINK_CREATE */
 	return bpf_program__attach_fd(prog, ifindex, 0, "xdp");
 }
 
-struct bpf_link *bpf_program__attach_freplace(struct bpf_program *prog,
+struct bpf_link *bpf_program__attach_freplace(const struct bpf_program *prog,
 					      int target_fd,
 					      const char *attach_func_name)
 {
···
 }
 
 struct bpf_link *
-bpf_program__attach_iter(struct bpf_program *prog,
+bpf_program__attach_iter(const struct bpf_program *prog,
 			 const struct bpf_iter_attach_opts *opts)
 {
 	DECLARE_LIBBPF_OPTS(bpf_link_create_opts, link_create_opts);
···
 	return link;
 }
 
-static struct bpf_link *attach_iter(const struct bpf_sec_def *sec,
-				    struct bpf_program *prog)
+static struct bpf_link *attach_iter(const struct bpf_program *prog)
 {
 	return bpf_program__attach_iter(prog, NULL);
 }
 
-struct bpf_link *bpf_program__attach(struct bpf_program *prog)
+struct bpf_link *bpf_program__attach(const struct bpf_program *prog)
 {
-	const struct bpf_sec_def *sec_def;
-
-	sec_def = find_sec_def(prog->sec_name);
-	if (!sec_def || !sec_def->attach_fn)
+	if (!prog->sec_def || !prog->sec_def->attach_fn)
 		return libbpf_err_ptr(-ESRCH);
 
-	return sec_def->attach_fn(sec_def, prog);
+	return prog->sec_def->attach_fn(prog);
 }
 
 static int bpf_link__detach_struct_ops(struct bpf_link *link)
···
 	return 0;
 }
 
-struct bpf_link *bpf_map__attach_struct_ops(struct bpf_map *map)
+struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map)
 {
 	struct bpf_struct_ops *st_ops;
 	struct bpf_link *link;
···
 {
 	int btf_obj_fd = 0, btf_id = 0, err;
 
-	if (!prog || attach_prog_fd < 0 || !attach_func_name)
+	if (!prog || attach_prog_fd < 0)
 		return libbpf_err(-EINVAL);
 
 	if (prog->obj->loaded)
 		return libbpf_err(-EINVAL);
+
+	if (attach_prog_fd && !attach_func_name) {
+		/* remember attach_prog_fd and let bpf_program__load() find
+		 * BTF ID during the program load
+		 */
+		prog->attach_prog_fd = attach_prog_fd;
+		return 0;
+	}
 
 	if (attach_prog_fd) {
 		btf_id = libbpf_find_prog_btf_id(attach_func_name,
···
 		if (btf_id < 0)
 			return libbpf_err(btf_id);
 	} else {
+		if (!attach_func_name)
+			return libbpf_err(-EINVAL);
+
 		/* load btf_vmlinux, if not yet */
 		err = bpf_object__load_vmlinux_btf(prog->obj, true);
 		if (err)
···
 	for (i = 0; i < s->prog_cnt; i++) {
 		struct bpf_program *prog = *s->progs[i].prog;
 		struct bpf_link **link = s->progs[i].link;
-		const struct bpf_sec_def *sec_def;
 
 		if (!prog->load)
 			continue;
 
-		sec_def = find_sec_def(prog->sec_name);
-		if (!sec_def || !sec_def->attach_fn)
+		/* auto-attaching not supported for this program */
+		if (!prog->sec_def || !prog->sec_def->attach_fn)
 			continue;
 
-		*link = sec_def->attach_fn(sec_def, prog);
+		*link = bpf_program__attach(prog);
 		err = libbpf_get_error(*link);
 		if (err) {
 			pr_warn("failed to auto-attach program '%s': %d\n",

tools/lib/bpf/libbpf.h

···
 	 * Non-relocatable instructions are replaced with invalid ones to
 	 * prevent accidental errors.
 	 * */
+	LIBBPF_DEPRECATED_SINCE(0, 6, "field has no effect")
 	bool relaxed_core_relocs;
 	/* maps that set the 'pinning' attribute in their definition will have
 	 * their pin_path attribute set to a file in this directory, and be
 	 * auto-pinned to that path on load; defaults to "/sys/fs/bpf".
 	 */
 	const char *pin_root_path;
+
+	LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_program__set_attach_target() on each individual bpf_program")
 	__u32 attach_prog_fd;
 	/* Additional kernel config content that augments and overrides
 	 * system Kconfig for CONFIG_xxx externs.
···
 LIBBPF_API int bpf_link__destroy(struct bpf_link *link);
 
 LIBBPF_API struct bpf_link *
-bpf_program__attach(struct bpf_program *prog);
+bpf_program__attach(const struct bpf_program *prog);
 
 struct bpf_perf_event_opts {
 	/* size of this struct, for forward/backward compatiblity */
···
 #define bpf_perf_event_opts__last_field bpf_cookie
 
 LIBBPF_API struct bpf_link *
-bpf_program__attach_perf_event(struct bpf_program *prog, int pfd);
+bpf_program__attach_perf_event(const struct bpf_program *prog, int pfd);
 
 LIBBPF_API struct bpf_link *
-bpf_program__attach_perf_event_opts(struct bpf_program *prog, int pfd,
+bpf_program__attach_perf_event_opts(const struct bpf_program *prog, int pfd,
 				    const struct bpf_perf_event_opts *opts);
 
 struct bpf_kprobe_opts {
···
 #define bpf_kprobe_opts__last_field retprobe
 
 LIBBPF_API struct bpf_link *
-bpf_program__attach_kprobe(struct bpf_program *prog, bool retprobe,
+bpf_program__attach_kprobe(const struct bpf_program *prog, bool retprobe,
 			   const char *func_name);
 LIBBPF_API struct bpf_link *
-bpf_program__attach_kprobe_opts(struct bpf_program *prog,
+bpf_program__attach_kprobe_opts(const struct bpf_program *prog,
                                 const char *func_name,
                                 const struct bpf_kprobe_opts *opts);
 
···
 #define bpf_uprobe_opts__last_field retprobe
 
 LIBBPF_API struct bpf_link *
-bpf_program__attach_uprobe(struct bpf_program *prog, bool retprobe,
+bpf_program__attach_uprobe(const struct bpf_program *prog, bool retprobe,
 			   pid_t pid, const char *binary_path,
 			   size_t func_offset);
 LIBBPF_API struct bpf_link *
-bpf_program__attach_uprobe_opts(struct bpf_program *prog, pid_t pid,
+bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid,
 				const char *binary_path, size_t func_offset,
 				const struct bpf_uprobe_opts *opts);
 
···
 #define bpf_tracepoint_opts__last_field bpf_cookie
 
 LIBBPF_API struct bpf_link *
-bpf_program__attach_tracepoint(struct bpf_program *prog,
+bpf_program__attach_tracepoint(const struct bpf_program *prog,
 			       const char *tp_category,
 			       const char *tp_name);
 LIBBPF_API struct bpf_link *
-bpf_program__attach_tracepoint_opts(struct bpf_program *prog,
+bpf_program__attach_tracepoint_opts(const struct bpf_program *prog,
 				    const char *tp_category,
 				    const char *tp_name,
 				    const struct bpf_tracepoint_opts *opts);
 
 LIBBPF_API struct bpf_link *
-bpf_program__attach_raw_tracepoint(struct bpf_program *prog,
+bpf_program__attach_raw_tracepoint(const struct bpf_program *prog,
 				   const char *tp_name);
 LIBBPF_API struct bpf_link *
-bpf_program__attach_trace(struct bpf_program *prog);
+bpf_program__attach_trace(const struct bpf_program *prog);
 LIBBPF_API struct bpf_link *
-bpf_program__attach_lsm(struct bpf_program *prog);
+bpf_program__attach_lsm(const struct bpf_program *prog);
 LIBBPF_API struct bpf_link *
-bpf_program__attach_cgroup(struct bpf_program *prog, int cgroup_fd);
+bpf_program__attach_cgroup(const struct bpf_program *prog, int cgroup_fd);
 LIBBPF_API struct bpf_link *
-bpf_program__attach_netns(struct bpf_program *prog, int netns_fd);
+bpf_program__attach_netns(const struct bpf_program *prog, int netns_fd);
 LIBBPF_API struct bpf_link *
-bpf_program__attach_xdp(struct bpf_program *prog, int ifindex);
+bpf_program__attach_xdp(const struct bpf_program *prog, int ifindex);
 LIBBPF_API struct bpf_link *
-bpf_program__attach_freplace(struct bpf_program *prog,
+bpf_program__attach_freplace(const struct bpf_program *prog,
 			     int target_fd, const char *attach_func_name);
 
 struct bpf_map;
 
-LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(struct bpf_map *map);
+LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map);
 
 struct bpf_iter_attach_opts {
 	size_t sz; /* size of this struct for forward/backward compatibility */
···
 #define bpf_iter_attach_opts__last_field link_info_len
 
 LIBBPF_API struct bpf_link *
-bpf_program__attach_iter(struct bpf_program *prog,
+bpf_program__attach_iter(const struct bpf_program *prog,
 			 const struct bpf_iter_attach_opts *opts);
 
 struct bpf_insn;
···
 	size_t sz; /* size of this struct, for forward/backward compatibility */
 
 	const char *name;
-	void *data;
+	const void *data;
 	size_t data_sz;
 
 	struct bpf_object **obj;

tools/lib/bpf/libbpf.map

···
 		btf_dump__dump_type_data;
 		libbpf_set_strict_mode;
 } LIBBPF_0.4.0;
+
+LIBBPF_0.6.0 {
+	global:
+		btf__add_tag;
+} LIBBPF_0.5.0;

tools/lib/bpf/libbpf_common.h

···
 #define __LIBBPF_LIBBPF_COMMON_H
 
 #include <string.h>
+#include "libbpf_version.h"
 
 #ifndef LIBBPF_API
 #define LIBBPF_API __attribute__((visibility("default")))
 #endif
 
 #define LIBBPF_DEPRECATED(msg) __attribute__((deprecated(msg)))
+
+/* Mark a symbol as deprecated when libbpf version is >= {major}.{minor} */
+#define LIBBPF_DEPRECATED_SINCE(major, minor, msg)			    \
+	__LIBBPF_MARK_DEPRECATED_ ## major ## _ ## minor		    \
+		(LIBBPF_DEPRECATED("libbpf v" # major "." # minor "+: " msg))
+
+#define __LIBBPF_CURRENT_VERSION_GEQ(major, minor)			    \
+	(LIBBPF_MAJOR_VERSION > (major) ||				    \
+	 (LIBBPF_MAJOR_VERSION == (major) && LIBBPF_MINOR_VERSION >= (minor)))
+
+/* Add checks for other versions below when planning deprecation of API symbols
+ * with the LIBBPF_DEPRECATED_SINCE macro.
+ */
+#if __LIBBPF_CURRENT_VERSION_GEQ(0, 6)
+#define __LIBBPF_MARK_DEPRECATED_0_6(X) X
+#else
+#define __LIBBPF_MARK_DEPRECATED_0_6(X)
+#endif
+#if __LIBBPF_CURRENT_VERSION_GEQ(0, 7)
+#define __LIBBPF_MARK_DEPRECATED_0_7(X) X
+#else
+#define __LIBBPF_MARK_DEPRECATED_0_7(X)
+#endif
 
 /* Helper macro to declare and initialize libbpf options struct
  *

tools/lib/bpf/libbpf_internal.h

···
 #define BTF_VAR_SECINFO_ENC(type, offset, size) (type), (offset), (size)
 #define BTF_TYPE_FLOAT_ENC(name, sz) \
 	BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_FLOAT, 0, 0), sz)
+#define BTF_TYPE_TAG_ENC(value, type, component_idx) \
+	BTF_TYPE_ENC(value, BTF_INFO_ENC(BTF_KIND_TAG, 0, 0), type), (component_idx)
 
 #ifndef likely
 #define likely(x) __builtin_expect(!!(x), 1)
···
 /* Symbol versioning is different between static and shared library.
  * Properly versioned symbols are needed for shared library, but
  * only the symbol of the new version is needed for static library.
+ * Starting with GNU C 10, use symver attribute instead of .symver assembler
+ * directive, which works better with GCC LTO builds.
  */
-#ifdef SHARED
-# define COMPAT_VERSION(internal_name, api_name, version) \
+#if defined(SHARED) && defined(__GNUC__) && __GNUC__ >= 10
+
+#define DEFAULT_VERSION(internal_name, api_name, version) \
+	__attribute__((symver(#api_name "@@" #version)))
+#define COMPAT_VERSION(internal_name, api_name, version) \
+	__attribute__((symver(#api_name "@" #version)))
+
+#elif defined(SHARED)
+
+#define COMPAT_VERSION(internal_name, api_name, version) \
 	asm(".symver " #internal_name "," #api_name "@" #version);
-# define DEFAULT_VERSION(internal_name, api_name, version) \
+#define DEFAULT_VERSION(internal_name, api_name, version) \
 	asm(".symver " #internal_name "," #api_name "@@" #version);
-#else
-# define COMPAT_VERSION(internal_name, api_name, version)
-# define DEFAULT_VERSION(internal_name, api_name, version) \
+
+#else /* !SHARED */
+
+#define COMPAT_VERSION(internal_name, api_name, version)
+#define DEFAULT_VERSION(internal_name, api_name, version) \
 	extern typeof(internal_name) api_name \
 	__attribute__((alias(#internal_name)));
+
 #endif
 
 extern void libbpf_print(enum libbpf_print_level level,

tools/lib/bpf/libbpf_version.h

···
+/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
+/* Copyright (C) 2021 Facebook */
+#ifndef __LIBBPF_VERSION_H
+#define __LIBBPF_VERSION_H
+
+#define LIBBPF_MAJOR_VERSION 0
+#define LIBBPF_MINOR_VERSION 6
+
+#endif /* __LIBBPF_VERSION_H */

tools/lib/bpf/xsk.c

···
 	return err;
 }
 
+DEFAULT_VERSION(xsk_umem__create_v0_0_4, xsk_umem__create, LIBBPF_0.0.4)
 int xsk_umem__create_v0_0_4(struct xsk_umem **umem_ptr, void *umem_area,
 			    __u64 size, struct xsk_ring_prod *fill,
 			    struct xsk_ring_cons *comp,
···
 	__u32 frame_headroom;
 };
 
+COMPAT_VERSION(xsk_umem__create_v0_0_2, xsk_umem__create, LIBBPF_0.0.2)
 int xsk_umem__create_v0_0_2(struct xsk_umem **umem_ptr, void *umem_area,
 			    __u64 size, struct xsk_ring_prod *fill,
 			    struct xsk_ring_cons *comp,
···
 	return xsk_umem__create_v0_0_4(umem_ptr, umem_area, size, fill, comp,
 					&config);
 }
-COMPAT_VERSION(xsk_umem__create_v0_0_2, xsk_umem__create, LIBBPF_0.0.2)
-DEFAULT_VERSION(xsk_umem__create_v0_0_4, xsk_umem__create, LIBBPF_0.0.4)
 
 static enum xsk_prog get_xsk_prog(void)
 {

tools/testing/selftests/bpf/.gitignore

···
 FEATURE-DUMP.libbpf
 fixdep
 test_dev_cgroup
-/test_progs*
-!test_progs.h
+/test_progs
+/test_progs-no_alu32
+/test_progs-bpf_gcc
 test_verifier_log
 feature
 test_sock

tools/testing/selftests/bpf/Makefile

···
 	$(Q)$(CXX) $(CFLAGS) $(filter %.a %.o %.cpp,$^) $(LDLIBS) -o $@
 
 # Benchmark runner
-$(OUTPUT)/bench_%.o: benchs/bench_%.c bench.h
+$(OUTPUT)/bench_%.o: benchs/bench_%.c bench.h $(BPFOBJ)
 	$(call msg,CC,,$@)
 	$(Q)$(CC) $(CFLAGS) -c $(filter %.c,$^) $(LDLIBS) -o $@
 $(OUTPUT)/bench_rename.o: $(OUTPUT)/test_overhead.skel.h
 $(OUTPUT)/bench_trigger.o: $(OUTPUT)/trigger_bench.skel.h
 $(OUTPUT)/bench_ringbufs.o: $(OUTPUT)/ringbuf_bench.skel.h \
 			    $(OUTPUT)/perfbuf_bench.skel.h
-$(OUTPUT)/bench.o: bench.h testing_helpers.h
+$(OUTPUT)/bench.o: bench.h testing_helpers.h $(BPFOBJ)
 $(OUTPUT)/bench: LDLIBS += -lm
 $(OUTPUT)/bench: $(OUTPUT)/bench.o $(OUTPUT)/testing_helpers.o \
 		 $(OUTPUT)/bench_count.o \

tools/testing/selftests/bpf/README.rst

···
 
 __ https://reviews.llvm.org/D93563
 
+btf_tag test and Clang version
+==============================
+
+The btf_tag selftest require LLVM support to recognize the btf_tag attribute.
+It was introduced in `Clang 14`__.
+
+Without it, the btf_tag selftest will be skipped and you will observe:
+
+.. code-block:: console
+
+  #<test_num> btf_tag:SKIP
+
+__ https://reviews.llvm.org/D106614
+
 Clang dependencies for static linking tests
 ===========================================
 

tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c

···
 
 DEFINE_PER_CPU(int, bpf_testmod_ksym_percpu) = 123;
 
+noinline int bpf_testmod_loop_test(int n)
+{
+	int i, sum = 0;
+
+	/* the primary goal of this test is to test LBR. Create a lot of
+	 * branches in the function, so we can catch it easily.
+	 */
+	for (i = 0; i < n; i++)
+		sum += i;
+	return sum;
+}
+
 noinline ssize_t
 bpf_testmod_test_read(struct file *file, struct kobject *kobj,
 		      struct bin_attribute *bin_attr,
···
 		.len = len,
 	};
 
-	trace_bpf_testmod_test_read(current, &ctx);
+	/* This is always true. Use the check to make sure the compiler
+	 * doesn't remove bpf_testmod_loop_test.
+	 */
+	if (bpf_testmod_loop_test(101) > 100)
+		trace_bpf_testmod_test_read(current, &ctx);
 
 	return -EIO; /* always fail */
 }
···
 MODULE_AUTHOR("Andrii Nakryiko");
 MODULE_DESCRIPTION("BPF selftests module");
 MODULE_LICENSE("Dual BSD/GPL");
-

tools/testing/selftests/bpf/btf_helpers.c

···
 	[BTF_KIND_VAR]		= "VAR",
 	[BTF_KIND_DATASEC]	= "DATASEC",
 	[BTF_KIND_FLOAT]	= "FLOAT",
+	[BTF_KIND_TAG]		= "TAG",
 };
 
 static const char *btf_kind_str(__u16 kind)
 {
-	if (kind > BTF_KIND_DATASEC)
+	if (kind > BTF_KIND_TAG)
 		return "UNKNOWN";
 	return btf_kind_str_mapping[kind];
 }
···
 	}
 	case BTF_KIND_FLOAT:
 		fprintf(out, " size=%u", t->size);
+		break;
+	case BTF_KIND_TAG:
+		fprintf(out, " type_id=%u component_idx=%d",
+			t->type, btf_tag(t)->component_idx);
 		break;
 	default:
 		break;

tools/testing/selftests/bpf/prog_tests/bpf_iter.c

···
 
 static void test_bpf_hash_map(void)
 {
-	__u32 expected_key_a = 0, expected_key_b = 0, expected_key_c = 0;
+	__u32 expected_key_a = 0, expected_key_b = 0;
 	DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
 	struct bpf_iter_bpf_hash_map *skel;
 	int err, i, len, map_fd, iter_fd;
···
 		val = i + 4;
 		expected_key_a += key.a;
 		expected_key_b += key.b;
-		expected_key_c += key.c;
 		expected_val += val;
 
 		err = bpf_map_update_elem(map_fd, &key, &val, BPF_ANY);
···
 
 static void test_bpf_percpu_hash_map(void)
 {
-	__u32 expected_key_a = 0, expected_key_b = 0, expected_key_c = 0;
+	__u32 expected_key_a = 0, expected_key_b = 0;
 	DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
 	struct bpf_iter_bpf_percpu_hash_map *skel;
 	int err, i, j, len, map_fd, iter_fd;
···
 		key.c = i + 3;
 		expected_key_a += key.a;
 		expected_key_b += key.b;
-		expected_key_c += key.c;
 
 		for (j = 0; j < bpf_num_possible_cpus(); j++) {
 			*(__u32 *)(val + j * 8) = i + j;

tools/testing/selftests/bpf/prog_tests/btf.c

···
 #define BTF_END_RAW 0xdeadbeef
 #define NAME_TBD 0xdeadb33f
 
-#define NAME_NTH(N) (0xffff0000 | N)
-#define IS_NAME_NTH(X) ((X & 0xffff0000) == 0xffff0000)
+#define NAME_NTH(N) (0xfffe0000 | N)
+#define IS_NAME_NTH(X) ((X & 0xffff0000) == 0xfffe0000)
 #define GET_NAME_NTH_IDX(X) (X & 0x0000ffff)
 
 #define MAX_NR_RAW_U32 1024
···
 	.err_str = "Invalid type_size",
 },
 
+{
+	.descr = "tag test #1, struct/member, well-formed",
+	.raw_types = {
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+		BTF_STRUCT_ENC(0, 2, 8),			/* [2] */
+		BTF_MEMBER_ENC(NAME_TBD, 1, 0),
+		BTF_MEMBER_ENC(NAME_TBD, 1, 32),
+		BTF_TAG_ENC(NAME_TBD, 2, -1),
+		BTF_TAG_ENC(NAME_TBD, 2, 0),
+		BTF_TAG_ENC(NAME_TBD, 2, 1),
+		BTF_END_RAW,
+	},
+	BTF_STR_SEC("\0m1\0m2\0tag1\0tag2\0tag3"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "tag_type_check_btf",
+	.key_size = sizeof(int),
+	.value_size = 8,
+	.key_type_id = 1,
+	.value_type_id = 2,
+	.max_entries = 1,
+},
+{
+	.descr = "tag test #2, union/member, well-formed",
+	.raw_types = {
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+		BTF_UNION_ENC(NAME_TBD, 2, 4),			/* [2] */
+		BTF_MEMBER_ENC(NAME_TBD, 1, 0),
+		BTF_MEMBER_ENC(NAME_TBD, 1, 0),
+		BTF_TAG_ENC(NAME_TBD, 2, -1),
+		BTF_TAG_ENC(NAME_TBD, 2, 0),
+		BTF_TAG_ENC(NAME_TBD, 2, 1),
+		BTF_END_RAW,
+	},
+	BTF_STR_SEC("\0t\0m1\0m2\0tag1\0tag2\0tag3"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "tag_type_check_btf",
+	.key_size = sizeof(int),
+	.value_size = 4,
+	.key_type_id = 1,
+	.value_type_id = 2,
+	.max_entries = 1,
+},
+{
+	.descr = "tag test #3, variable, well-formed",
+	.raw_types = {
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+		BTF_VAR_ENC(NAME_TBD, 1, 0),			/* [2] */
+		BTF_VAR_ENC(NAME_TBD, 1, 1),			/* [3] */
+		BTF_TAG_ENC(NAME_TBD, 2, -1),
+		BTF_TAG_ENC(NAME_TBD, 3, -1),
+		BTF_END_RAW,
+	},
+	BTF_STR_SEC("\0local\0global\0tag1\0tag2"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "tag_type_check_btf",
+	.key_size = sizeof(int),
+	.value_size = 4,
+	.key_type_id = 1,
+	.value_type_id = 1,
+	.max_entries = 1,
+},
+{
+	.descr = "tag test #4, func/parameter, well-formed",
+	.raw_types = {
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+		BTF_FUNC_PROTO_ENC(0, 2),			/* [2] */
+			BTF_FUNC_PROTO_ARG_ENC(NAME_TBD, 1),
+			BTF_FUNC_PROTO_ARG_ENC(NAME_TBD, 1),
+		BTF_FUNC_ENC(NAME_TBD, 2),			/* [3] */
+		BTF_TAG_ENC(NAME_TBD, 3, -1),
+		BTF_TAG_ENC(NAME_TBD, 3, 0),
+		BTF_TAG_ENC(NAME_TBD, 3, 1),
+		BTF_END_RAW,
+	},
+	BTF_STR_SEC("\0arg1\0arg2\0f\0tag1\0tag2\0tag3"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "tag_type_check_btf",
+	.key_size = sizeof(int),
+	.value_size = 4,
+	.key_type_id = 1,
+	.value_type_id = 1,
+	.max_entries = 1,
+},
+{
+	.descr = "tag test #5, invalid value",
+	.raw_types = {
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+		BTF_VAR_ENC(NAME_TBD, 1, 0),			/* [2] */
+		BTF_TAG_ENC(0, 2, -1),
+		BTF_END_RAW,
+	},
+	BTF_STR_SEC("\0local\0tag"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "tag_type_check_btf",
+	.key_size = sizeof(int),
+	.value_size = 4,
+	.key_type_id = 1,
+	.value_type_id = 1,
+	.max_entries = 1,
+	.btf_load_err = true,
+	.err_str = "Invalid value",
+},
+{
+	.descr = "tag test #6, invalid target type",
+	.raw_types = {
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+		BTF_TAG_ENC(NAME_TBD, 1, -1),
+		BTF_END_RAW,
+	},
+	BTF_STR_SEC("\0tag1"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "tag_type_check_btf",
+	.key_size = sizeof(int),
+	.value_size = 4,
+	.key_type_id = 1,
+	.value_type_id = 1,
+	.max_entries = 1,
+	.btf_load_err = true,
+	.err_str = "Invalid type",
+},
+{
+	.descr = "tag test #7, invalid vlen",
+	.raw_types = {
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+		BTF_VAR_ENC(NAME_TBD, 1, 0),			/* [2] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_TAG, 0, 1), 2), (0),
+		BTF_END_RAW,
+	},
+	BTF_STR_SEC("\0local\0tag1"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "tag_type_check_btf",
+	.key_size = sizeof(int),
+	.value_size = 4,
+	.key_type_id = 1,
+	.value_type_id = 1,
+	.max_entries = 1,
+	.btf_load_err = true,
+	.err_str = "vlen != 0",
+},
+{
+	.descr = "tag test #8, invalid kflag",
+	.raw_types = {
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+		BTF_VAR_ENC(NAME_TBD, 1, 0),			/* [2] */
+		BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_TAG, 1, 0), 2), (-1),
+		BTF_END_RAW,
+	},
+	BTF_STR_SEC("\0local\0tag1"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "tag_type_check_btf",
+	.key_size = sizeof(int),
+	.value_size = 4,
+	.key_type_id = 1,
+	.value_type_id = 1,
+	.max_entries = 1,
+	.btf_load_err = true,
+	.err_str = "Invalid btf_info kind_flag",
+},
+{
+	.descr = "tag test #9, var, invalid component_idx",
+	.raw_types = {
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+		BTF_VAR_ENC(NAME_TBD, 1, 0),			/* [2] */
+		BTF_TAG_ENC(NAME_TBD, 2, 0),
+		BTF_END_RAW,
+	},
+	BTF_STR_SEC("\0local\0tag"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "tag_type_check_btf",
+	.key_size = sizeof(int),
+	.value_size = 4,
+	.key_type_id = 1,
+	.value_type_id = 1,
+	.max_entries = 1,
+	.btf_load_err = true,
+	.err_str = "Invalid component_idx",
+},
+{
+	.descr = "tag test #10, struct member, invalid component_idx",
+	.raw_types = {
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+		BTF_STRUCT_ENC(0, 2, 8),			/* [2] */
+		BTF_MEMBER_ENC(NAME_TBD, 1, 0),
+		BTF_MEMBER_ENC(NAME_TBD, 1, 32),
+		BTF_TAG_ENC(NAME_TBD, 2, 2),
+		BTF_END_RAW,
+	},
+	BTF_STR_SEC("\0m1\0m2\0tag"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "tag_type_check_btf",
+	.key_size = sizeof(int),
+	.value_size = 8,
+	.key_type_id = 1,
+	.value_type_id = 2,
+	.max_entries = 1,
+	.btf_load_err = true,
+	.err_str = "Invalid component_idx",
+},
+{
+	.descr = "tag test #11, func parameter, invalid component_idx",
+	.raw_types = {
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+		BTF_FUNC_PROTO_ENC(0, 2),			/* [2] */
+			BTF_FUNC_PROTO_ARG_ENC(NAME_TBD, 1),
+			BTF_FUNC_PROTO_ARG_ENC(NAME_TBD, 1),
+		BTF_FUNC_ENC(NAME_TBD, 2),			/* [3] */
+		BTF_TAG_ENC(NAME_TBD, 3, 2),
+		BTF_END_RAW,
+	},
+	BTF_STR_SEC("\0arg1\0arg2\0f\0tag"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "tag_type_check_btf",
+	.key_size = sizeof(int),
+	.value_size = 4,
+	.key_type_id = 1,
+	.value_type_id = 1,
+	.max_entries = 1,
+	.btf_load_err = true,
+	.err_str = "Invalid component_idx",
+},
+{
+	.descr = "tag test #12, < -1 component_idx",
+	.raw_types = {
+		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+		BTF_FUNC_PROTO_ENC(0, 2),			/* [2] */
+			BTF_FUNC_PROTO_ARG_ENC(NAME_TBD, 1),
+			BTF_FUNC_PROTO_ARG_ENC(NAME_TBD, 1),
+		BTF_FUNC_ENC(NAME_TBD, 2),			/* [3] */
+		BTF_TAG_ENC(NAME_TBD, 3, -2),
+		BTF_END_RAW,
+	},
+	BTF_STR_SEC("\0arg1\0arg2\0f\0tag"),
+	.map_type = BPF_MAP_TYPE_ARRAY,
+	.map_name = "tag_type_check_btf",
+	.key_size = sizeof(int),
+	.value_size = 4,
+	.key_type_id = 1,
+	.value_type_id = 1,
+	.max_entries = 1,
+	.btf_load_err = true,
+	.err_str = "Invalid component_idx",
+},
+
 }; /* struct btf_raw_test raw_tests[] */
 
 static const char *get_next_str(const char *start, const char *end)
···
 				BTF_MEMBER_ENC(NAME_NTH(4), 5, 64),	/* const int *a;	*/
 				BTF_MEMBER_ENC(NAME_NTH(5), 2, 128),	/* int b[16];		*/
 				BTF_MEMBER_ENC(NAME_NTH(6), 1, 640),	/* int c;		*/
-				BTF_MEMBER_ENC(NAME_NTH(8), 13, 672),	/* float d;		*/
+				BTF_MEMBER_ENC(NAME_NTH(8), 15, 672),	/* float d;		*/
 			/* ptr -> [3] struct s */
 			BTF_PTR_ENC(3),							/* [4] */
 			/* ptr -> [6] const int */
 			BTF_PTR_ENC(6),							/* [5] */
 			/* const -> [1] int */
 			BTF_CONST_ENC(1),						/* [6] */
+			/* tag -> [3] struct s */
+			BTF_TAG_ENC(NAME_NTH(2), 3, -1),				/* [7] */
+			/* tag -> [3] struct s, member 1 */
+			BTF_TAG_ENC(NAME_NTH(2), 3, 1),					/* [8] */
 
 			/* full copy of the above */
-			BTF_TYPE_INT_ENC(NAME_NTH(1), BTF_INT_SIGNED, 0, 32, 4),	/* [7] */
-			BTF_TYPE_ARRAY_ENC(7, 7, 16),					/* [8] */
-			BTF_STRUCT_ENC(NAME_NTH(2), 5, 88),				/* [9] */
-				BTF_MEMBER_ENC(NAME_NTH(3), 10, 0),
-				BTF_MEMBER_ENC(NAME_NTH(4), 11, 64),
-				BTF_MEMBER_ENC(NAME_NTH(5), 8, 128),
-				BTF_MEMBER_ENC(NAME_NTH(6), 7, 640),
-				BTF_MEMBER_ENC(NAME_NTH(8), 13, 672),
-			BTF_PTR_ENC(9),							/* [10] */
-			BTF_PTR_ENC(12),						/* [11] */
-			BTF_CONST_ENC(7),						/* [12] */
-			BTF_TYPE_FLOAT_ENC(NAME_NTH(7), 4),				/* [13] */
+			BTF_TYPE_INT_ENC(NAME_NTH(1), BTF_INT_SIGNED, 0, 32, 4),	/* [9] */
+			BTF_TYPE_ARRAY_ENC(9, 9, 16),					/* [10] */
+			BTF_STRUCT_ENC(NAME_NTH(2), 5, 88),				/* [11] */
+				BTF_MEMBER_ENC(NAME_NTH(3), 12, 0),
+				BTF_MEMBER_ENC(NAME_NTH(4), 13, 64),
+				BTF_MEMBER_ENC(NAME_NTH(5), 10, 128),
+				BTF_MEMBER_ENC(NAME_NTH(6), 9, 640),
+				BTF_MEMBER_ENC(NAME_NTH(8), 15, 672),
+			BTF_PTR_ENC(11),						/* [12] */
+			BTF_PTR_ENC(14),						/* [13] */
+			BTF_CONST_ENC(9),						/* [14] */
+			BTF_TYPE_FLOAT_ENC(NAME_NTH(7), 4),				/* [15] */
+			BTF_TAG_ENC(NAME_NTH(2), 11, -1),				/* [16] */
+			BTF_TAG_ENC(NAME_NTH(2), 11, 1),				/* [17] */
 			BTF_END_RAW,
 		},
 		BTF_STR_SEC("\0int\0s\0next\0a\0b\0c\0float\0d"),
···
 				BTF_MEMBER_ENC(NAME_NTH(1), 5, 64),	/* const int *a;	*/
 				BTF_MEMBER_ENC(NAME_NTH(2), 2, 128),	/* int b[16];		*/
 				BTF_MEMBER_ENC(NAME_NTH(3), 1, 640),	/* int c;		*/
-				BTF_MEMBER_ENC(NAME_NTH(4), 7, 672),	/* float d;		*/
+				BTF_MEMBER_ENC(NAME_NTH(4), 9, 672),	/* float d;		*/
 			/* ptr -> [3] struct s */
 			BTF_PTR_ENC(3),							/* [4] */
 			/* ptr -> [6] const int */
 			BTF_PTR_ENC(6),							/* [5] */
 			/* const -> [1] int */
 			BTF_CONST_ENC(1),						/* [6] */
-			BTF_TYPE_FLOAT_ENC(NAME_NTH(7), 4),				/* [7] */
+			BTF_TAG_ENC(NAME_NTH(2), 3, -1),				/* [7] */
+			BTF_TAG_ENC(NAME_NTH(2), 3, 1),					/* [8] */
+			BTF_TYPE_FLOAT_ENC(NAME_NTH(7), 4),				/* [9] */
 			BTF_END_RAW,
 		},
 		BTF_STR_SEC("\0a\0b\0c\0d\0int\0float\0next\0s"),
···
 				BTF_FUNC_PROTO_ARG_ENC(NAME_TBD, 8),
 			BTF_FUNC_ENC(NAME_TBD, 12),					/* [13] func */
 			BTF_TYPE_FLOAT_ENC(NAME_TBD, 2),				/* [14] float */
+			BTF_TAG_ENC(NAME_TBD, 13, -1),					/* [15] tag */
+			BTF_TAG_ENC(NAME_TBD, 13, 1),					/* [16] tag */
 			BTF_END_RAW,
 		},
-		BTF_STR_SEC("\0A\0B\0C\0D\0E\0F\0G\0H\0I\0J\0K\0L\0M\0N"),
+		BTF_STR_SEC("\0A\0B\0C\0D\0E\0F\0G\0H\0I\0J\0K\0L\0M\0N\0O\0P"),
 	},
 	.expect = {
 		.raw_types = {
···
 				BTF_FUNC_PROTO_ARG_ENC(NAME_TBD, 8),
 			BTF_FUNC_ENC(NAME_TBD, 12),					/* [13] func */
 			BTF_TYPE_FLOAT_ENC(NAME_TBD, 2),				/* [14] float */
+			BTF_TAG_ENC(NAME_TBD, 13, -1),					/* [15] tag */
+			BTF_TAG_ENC(NAME_TBD, 13, 1),					/* [16] tag */
 			BTF_END_RAW,
 		},
-		BTF_STR_SEC("\0A\0B\0C\0D\0E\0F\0G\0H\0I\0J\0K\0L\0M\0N"),
+		BTF_STR_SEC("\0A\0B\0C\0D\0E\0F\0G\0H\0I\0J\0K\0L\0M\0N\0O\0P"),
 	},
 	.opts = {
 		.dont_resolve_fwds = false,
···
 		.dedup_table_size = 1
 	},
 },
+{
+	.descr = "dedup: func/func_arg/var tags",
+	.input = {
+		.raw_types = {
+			/* int */
+			BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+			/* static int t */
+			BTF_VAR_ENC(NAME_NTH(1), 1, 0),			/* [2] */
+			/* void f(int a1, int a2) */
+			BTF_FUNC_PROTO_ENC(0, 2),			/* [3] */
+				BTF_FUNC_PROTO_ARG_ENC(NAME_NTH(2), 1),
+				BTF_FUNC_PROTO_ARG_ENC(NAME_NTH(3), 1),
+			BTF_FUNC_ENC(NAME_NTH(4), 2),			/* [4] */
+			/* tag -> t */
+			BTF_TAG_ENC(NAME_NTH(5), 2, -1),		/* [5] */
+			BTF_TAG_ENC(NAME_NTH(5), 2, -1),		/* [6] */
+			/* tag -> func */
+			BTF_TAG_ENC(NAME_NTH(5), 4, -1),		/* [7] */
+			BTF_TAG_ENC(NAME_NTH(5), 4, -1),		/* [8] */
+			/* tag -> func arg a1 */
+			BTF_TAG_ENC(NAME_NTH(5), 4, 1),			/* [9] */
+			BTF_TAG_ENC(NAME_NTH(5), 4, 1),			/* [10] */
+			BTF_END_RAW,
+		},
+		BTF_STR_SEC("\0t\0a1\0a2\0f\0tag"),
+	},
+	.expect = {
+		.raw_types = {
+			BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+			BTF_VAR_ENC(NAME_NTH(1), 1, 0),			/* [2] */
+			BTF_FUNC_PROTO_ENC(0, 2),			/* [3] */
+				BTF_FUNC_PROTO_ARG_ENC(NAME_NTH(2), 1),
+				BTF_FUNC_PROTO_ARG_ENC(NAME_NTH(3), 1),
+			BTF_FUNC_ENC(NAME_NTH(4), 2),			/* [4] */
+			BTF_TAG_ENC(NAME_NTH(5), 2, -1),		/* [5] */
+			BTF_TAG_ENC(NAME_NTH(5), 4, -1),		/* [6] */
+			BTF_TAG_ENC(NAME_NTH(5), 4, 1),			/* [7] */
+			BTF_END_RAW,
+		},
+		BTF_STR_SEC("\0t\0a1\0a2\0f\0tag"),
+	},
+	.opts = {
+		.dont_resolve_fwds = false,
+	},
+},
+{
+	.descr = "dedup: func/func_param tags",
+	.input = {
+		.raw_types = {
+			/* int */
+			BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+			/* void f(int a1, int a2) */
+			BTF_FUNC_PROTO_ENC(0, 2),			/* [2] */
+				BTF_FUNC_PROTO_ARG_ENC(NAME_NTH(1), 1),
+				BTF_FUNC_PROTO_ARG_ENC(NAME_NTH(2), 1),
+			BTF_FUNC_ENC(NAME_NTH(3), 2),			/* [3] */
+			/* void f(int a1, int a2) */
+			BTF_FUNC_PROTO_ENC(0, 2),			/* [4] */
+				BTF_FUNC_PROTO_ARG_ENC(NAME_NTH(1), 1),
+				BTF_FUNC_PROTO_ARG_ENC(NAME_NTH(2), 1),
+			BTF_FUNC_ENC(NAME_NTH(3), 4),			/* [5] */
+			/* tag -> f: tag1, tag2 */
+			BTF_TAG_ENC(NAME_NTH(4), 3, -1),		/* [6] */
+			BTF_TAG_ENC(NAME_NTH(5), 3, -1),		/* [7] */
+			/* tag -> f/a2: tag1, tag2 */
+			BTF_TAG_ENC(NAME_NTH(4), 3, 1),			/* [8] */
+			BTF_TAG_ENC(NAME_NTH(5), 3, 1),			/* [9] */
+			/* tag -> f: tag1, tag3 */
+			BTF_TAG_ENC(NAME_NTH(4), 5, -1),		/* [10] */
+			BTF_TAG_ENC(NAME_NTH(6), 5, -1),		/* [11] */
+			/* tag -> f/a2: tag1, tag3 */
+			BTF_TAG_ENC(NAME_NTH(4), 5, 1),			/* [12] */
+			BTF_TAG_ENC(NAME_NTH(6), 5, 1),			/* [13] */
+			BTF_END_RAW,
+		},
+		BTF_STR_SEC("\0a1\0a2\0f\0tag1\0tag2\0tag3"),
+	},
+	.expect = {
+		.raw_types = {
+			BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+			BTF_FUNC_PROTO_ENC(0, 2),			/* [2] */
+				BTF_FUNC_PROTO_ARG_ENC(NAME_NTH(1), 1),
+				BTF_FUNC_PROTO_ARG_ENC(NAME_NTH(2), 1),
+			BTF_FUNC_ENC(NAME_NTH(3), 2),			/* [3] */
+			BTF_TAG_ENC(NAME_NTH(4), 3, -1),		/* [4] */
+			BTF_TAG_ENC(NAME_NTH(5), 3, -1),		/* [5] */
+			BTF_TAG_ENC(NAME_NTH(6), 3, -1),		/* [6] */
+			BTF_TAG_ENC(NAME_NTH(4), 3, 1),			/* [7] */
+			BTF_TAG_ENC(NAME_NTH(5), 3, 1),			/* [8] */
+			BTF_TAG_ENC(NAME_NTH(6), 3, 1),			/* [9] */
+			BTF_END_RAW,
+		},
+		BTF_STR_SEC("\0a1\0a2\0f\0tag1\0tag2\0tag3"),
+	},
+	.opts = {
+		.dont_resolve_fwds = false,
+	},
+},
+{
+	.descr = "dedup: struct/struct_member tags",
+	.input = {
+		.raw_types = {
+			/* int */
+			BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+			BTF_STRUCT_ENC(NAME_NTH(1), 2, 8),		/* [2] */
+				BTF_MEMBER_ENC(NAME_NTH(2), 1, 0),
+				BTF_MEMBER_ENC(NAME_NTH(3), 1, 32),
+			BTF_STRUCT_ENC(NAME_NTH(1), 2, 8),		/* [3] */
+				BTF_MEMBER_ENC(NAME_NTH(2), 1, 0),
+				BTF_MEMBER_ENC(NAME_NTH(3), 1, 32),
+			/* tag -> t: tag1, tag2 */
+			BTF_TAG_ENC(NAME_NTH(4), 2, -1),		/* [4] */
+			BTF_TAG_ENC(NAME_NTH(5), 2, -1),		/* [5] */
+			/* tag -> t/m2: tag1, tag2 */
+			BTF_TAG_ENC(NAME_NTH(4), 2, 1),			/* [6] */
+			BTF_TAG_ENC(NAME_NTH(5), 2, 1),			/* [7] */
+			/* tag -> t: tag1, tag3 */
+			BTF_TAG_ENC(NAME_NTH(4), 3, -1),		/* [8] */
+			BTF_TAG_ENC(NAME_NTH(6), 3, -1),		/* [9] */
+			/* tag -> t/m2: tag1, tag3 */
+			BTF_TAG_ENC(NAME_NTH(4), 3, 1),			/* [10] */
+			BTF_TAG_ENC(NAME_NTH(6), 3, 1),			/* [11] */
+			BTF_END_RAW,
+		},
+		BTF_STR_SEC("\0t\0m1\0m2\0tag1\0tag2\0tag3"),
+	},
+	.expect = {
+		.raw_types = {
+			BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
+			BTF_STRUCT_ENC(NAME_NTH(1), 2, 8),		/* [2] */
+				BTF_MEMBER_ENC(NAME_NTH(2), 1, 0),
+				BTF_MEMBER_ENC(NAME_NTH(3), 1, 32),
+			BTF_TAG_ENC(NAME_NTH(4), 2, -1),		/* [3] */
+			BTF_TAG_ENC(NAME_NTH(5), 2, -1),		/* [4] */
+			BTF_TAG_ENC(NAME_NTH(6), 2, -1),		/* [5] */
+			BTF_TAG_ENC(NAME_NTH(4), 2, 1),			/* [6] */
+			BTF_TAG_ENC(NAME_NTH(5), 2, 1),			/* [7] */
+			BTF_TAG_ENC(NAME_NTH(6), 2, 1),			/* [8] */
+			BTF_END_RAW,
+		},
+		BTF_STR_SEC("\0t\0m1\0m2\0tag1\0tag2\0tag3"),
+	},
+	.opts = {
+		.dont_resolve_fwds = false,
+	},
+},
 
 };
 
···
 		return base_size + sizeof(struct btf_var);
 	case BTF_KIND_DATASEC:
 		return base_size + vlen * sizeof(struct btf_var_secinfo);
+	case BTF_KIND_TAG:
+		return base_size + sizeof(struct btf_tag);
 	default:
 		fprintf(stderr, "Unsupported BTF_KIND:%u\n", kind);
 		return -EINVAL;

tools/testing/selftests/bpf/prog_tests/btf_tag.c

···
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2021 Facebook */
+#include <test_progs.h>
+#include "tag.skel.h"
+
+void test_btf_tag(void)
+{
+	struct tag *skel;
+
+	skel = tag__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "btf_tag"))
+		return;
+
+	if (skel->rodata->skip_tests) {
+		printf("%s:SKIP: btf_tag attribute not supported", __func__);
+		test__skip();
+	}
+
+	tag__destroy(skel);
+}

tools/testing/selftests/bpf/prog_tests/btf_write.c

···
 		     "[17] DATASEC 'datasec1' size=12 vlen=1\n"
 		     "\ttype_id=1 offset=4 size=8", "raw_dump");
 
+	/* TAG */
+	id = btf__add_tag(btf, "tag1", 16, -1);
+	ASSERT_EQ(id, 18, "tag_id");
+	t = btf__type_by_id(btf, 18);
+	ASSERT_STREQ(btf__str_by_offset(btf, t->name_off), "tag1", "tag_value");
+	ASSERT_EQ(btf_kind(t), BTF_KIND_TAG, "tag_kind");
+	ASSERT_EQ(t->type, 16, "tag_type");
+	ASSERT_EQ(btf_tag(t)->component_idx, -1, "tag_component_idx");
+	ASSERT_STREQ(btf_type_raw_dump(btf, 18),
+		     "[18] TAG 'tag1' type_id=16 component_idx=-1", "raw_dump");
+
+	id = btf__add_tag(btf, "tag2", 14, 1);
+	ASSERT_EQ(id, 19, "tag_id");
+	t = btf__type_by_id(btf, 19);
+	ASSERT_STREQ(btf__str_by_offset(btf, t->name_off), "tag2", "tag_value");
+	ASSERT_EQ(btf_kind(t), BTF_KIND_TAG, "tag_kind");
+	ASSERT_EQ(t->type, 14, "tag_type");
+	ASSERT_EQ(btf_tag(t)->component_idx, 1, "tag_component_idx");
+	ASSERT_STREQ(btf_type_raw_dump(btf, 19),
+		     "[19] TAG 'tag2' type_id=14 component_idx=1", "raw_dump");
+
 	btf__free(btf);
 }

tools/testing/selftests/bpf/prog_tests/core_reloc.c

···
 	.output_len = sizeof(struct core_reloc_module_output),		\
 	.prog_sec_name = sec_name,					\
 	.raw_tp_name = tp_name,						\
-	.trigger = trigger_module_test_read,				\
+	.trigger = __trigger_module_test_read,				\
 	.needs_testmod = true,						\
 }
 
···
 #define SIZE_CASE_COMMON(name)						\
 	.case_name = #name,						\
 	.bpf_obj_file = "test_core_reloc_size.o",			\
-	.btf_src_file = "btf__core_reloc_" #name ".o",			\
-	.relaxed_core_relocs = true
+	.btf_src_file = "btf__core_reloc_" #name ".o"
 
 #define SIZE_OUTPUT_DATA(type)						\
 	STRUCT_TO_CHAR_PTR(core_reloc_size_output) {			\
···
 	return 0;
 }
 
-static int trigger_module_test_read(const struct core_reloc_test_case *test)
+static int __trigger_module_test_read(const struct core_reloc_test_case *test)
 {
 	struct core_reloc_module_output *exp = (void *)test->output;
-	int fd, err;
 
-	fd = open("/sys/kernel/bpf_testmod", O_RDONLY);
-	err = -errno;
-	if (CHECK(fd < 0, "testmod_file_open", "failed: %d\n", err))
-		return err;
-
-	read(fd, NULL, exp->len); /* request expected number of bytes */
-	close(fd);
-
+	trigger_module_test_read(exp->len);
 	return 0;
 }
 

tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c

···
 	struct bpf_object *obj = NULL, *tgt_obj;
 	__u32 retval, tgt_prog_id, info_len;
 	struct bpf_prog_info prog_info = {};
-	struct bpf_program **prog = NULL;
+	struct bpf_program **prog = NULL, *p;
 	struct bpf_link **link = NULL;
 	int err, tgt_fd, i;
 	struct btf *btf;
···
 			    &tgt_obj, &tgt_fd);
 	if (!ASSERT_OK(err, "tgt_prog_load"))
 		return;
-	DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts,
-			    .attach_prog_fd = tgt_fd,
-			   );
 
 	info_len = sizeof(prog_info);
 	err = bpf_obj_get_info_by_fd(tgt_fd, &prog_info, &info_len);
···
 	if (!ASSERT_OK_PTR(prog, "prog_ptr"))
 		goto close_prog;
 
-	obj = bpf_object__open_file(obj_file, &opts);
+	obj = bpf_object__open_file(obj_file, NULL);
 	if (!ASSERT_OK_PTR(obj, "obj_open"))
 		goto close_prog;
+
+	bpf_object__for_each_program(p, obj) {
+		err = bpf_program__set_attach_target(p, tgt_fd, NULL);
+		ASSERT_OK(err, "set_attach_target");
+	}
 
 	err = bpf_object__load(obj);
 	if (!ASSERT_OK(err, "obj_load"))
···
 	struct bpf_link *freplace_link = NULL;
 	struct bpf_program *prog;
 	__u32 duration = 0;
-	int err, pkt_fd;
+	int err, pkt_fd, attach_prog_fd;
 
 	err = bpf_prog_load(tgt_name, BPF_PROG_TYPE_UNSPEC,
 			    &pkt_obj, &pkt_fd);
···
 	if (CHECK(err, "tgt_prog_load", "file %s err %d errno %d\n",
 		  tgt_name, err, errno))
 		return;
-	opts.attach_prog_fd = pkt_fd;
 
-	freplace_obj = bpf_object__open_file(freplace_name, &opts);
+	freplace_obj = bpf_object__open_file(freplace_name, NULL);
 	if (!ASSERT_OK_PTR(freplace_obj, "freplace_obj_open"))
 		goto out;
+
+	prog = bpf_program__next(NULL, freplace_obj);
+	err = bpf_program__set_attach_target(prog, pkt_fd, NULL);
+	ASSERT_OK(err, "freplace__set_attach_target");
 
 	err = bpf_object__load(freplace_obj);
 	if (CHECK(err, "freplace_obj_load", "err %d\n", err))
 		goto out;
 
-	prog = bpf_program__next(NULL, freplace_obj);
 	freplace_link = bpf_program__attach_trace(prog);
 	if (!ASSERT_OK_PTR(freplace_link, "freplace_attach_trace"))
 		goto out;
 
-	opts.attach_prog_fd = bpf_program__fd(prog);
-	fmod_obj = bpf_object__open_file(fmod_ret_name, &opts);
+	fmod_obj = bpf_object__open_file(fmod_ret_name, NULL);
 	if (!ASSERT_OK_PTR(fmod_obj, "fmod_obj_open"))
 		goto out;
+
+	attach_prog_fd = bpf_program__fd(prog);
+	prog = bpf_program__next(NULL, fmod_obj);
+	err = bpf_program__set_attach_target(prog, attach_prog_fd, NULL);
+	ASSERT_OK(err, "fmod_ret_set_attach_target");
 
 	err = bpf_object__load(fmod_obj);
 	if (CHECK(!err, "fmod_obj_load", "loading fmod_ret should fail\n"))
···
 }
 
 static void test_obj_load_failure_common(const char *obj_file,
-					  const char *target_obj_file)
-
+					 const char *target_obj_file)
 {
 	/*
 	 * standalone test that asserts failure to load freplace prog
 	 * because of invalid return code.
 	 */
 	struct bpf_object *obj = NULL, *pkt_obj;
+	struct bpf_program *prog;
 	int err, pkt_fd;
 	__u32 duration = 0;
 
···
 	if (CHECK(err, "tgt_prog_load", "file %s err %d errno %d\n",
 		  target_obj_file, err, errno))
 		return;
-	DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts,
-			    .attach_prog_fd = pkt_fd,
-			   );
 
-	obj = bpf_object__open_file(obj_file, &opts);
+	obj = bpf_object__open_file(obj_file, NULL);
 	if (!ASSERT_OK_PTR(obj, "obj_open"))
 		goto close_prog;
+
+	prog = bpf_program__next(NULL, obj);
+	err = bpf_program__set_attach_target(prog, pkt_fd, NULL);
+	ASSERT_OK(err, "set_attach_target");
 
 	/* It should fail to load the program */
 	err = bpf_object__load(obj);

tools/testing/selftests/bpf/prog_tests/get_branch_snapshot.c

···
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2021 Facebook */
+#include <test_progs.h>
+#include "get_branch_snapshot.skel.h"
+
+static int *pfd_array;
+static int cpu_cnt;
+
+static int create_perf_events(void)
+{
+	struct perf_event_attr attr = {0};
+	int cpu;
+
+	/* create perf event */
+	attr.size = sizeof(attr);
+	attr.type = PERF_TYPE_RAW;
+	attr.config = 0x1b00;
+	attr.sample_type = PERF_SAMPLE_BRANCH_STACK;
+	attr.branch_sample_type = PERF_SAMPLE_BRANCH_KERNEL |
+		PERF_SAMPLE_BRANCH_USER | PERF_SAMPLE_BRANCH_ANY;
+
+	cpu_cnt = libbpf_num_possible_cpus();
+	pfd_array = malloc(sizeof(int) * cpu_cnt);
+	if (!pfd_array) {
+		cpu_cnt = 0;
+		return 1;
+	}
+
+	for (cpu = 0; cpu < cpu_cnt; cpu++) {
+		pfd_array[cpu] = syscall(__NR_perf_event_open, &attr,
+					 -1, cpu, -1, PERF_FLAG_FD_CLOEXEC);
+		if (pfd_array[cpu] < 0)
+			break;
+	}
+
+	return cpu == 0;
+}
+
+static void close_perf_events(void)
+{
+	int cpu = 0;
+	int fd;
+
+	while (cpu++ < cpu_cnt) {
+		fd = pfd_array[cpu];
+		if (fd < 0)
+			break;
+		close(fd);
+	}
+	free(pfd_array);
+}
+
+void test_get_branch_snapshot(void)
+{
+	struct get_branch_snapshot *skel = NULL;
+	int err;
+
+	if (create_perf_events()) {
+		test__skip();  /* system doesn't support LBR */
+		goto cleanup;
+	}
+
+	skel = get_branch_snapshot__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "get_branch_snapshot__open_and_load"))
+		goto cleanup;
+
+	err = kallsyms_find("bpf_testmod_loop_test", &skel->bss->address_low);
+	if (!ASSERT_OK(err, "kallsyms_find"))
+		goto cleanup;
+
+	err = kallsyms_find_next("bpf_testmod_loop_test", &skel->bss->address_high);
+	if (!ASSERT_OK(err, "kallsyms_find_next"))
+		goto cleanup;
+
+	err = get_branch_snapshot__attach(skel);
+	if (!ASSERT_OK(err, "get_branch_snapshot__attach"))
+		goto cleanup;
+
+	trigger_module_test_read(100);
+
+	if (skel->bss->total_entries < 16) {
+		/* too few entries for the hit/waste test */
+		test__skip();
+		goto cleanup;
+	}
+
+	ASSERT_GT(skel->bss->test1_hits, 6, "find_looptest_in_lbr");
+
+	/* Given we stop LBR in software, we will waste a few entries.
+	 * But we should try to waste as few as possible entries. We are at
+	 * about 7 on x86_64 systems.
+	 * Add a check for < 10 so that we get heads-up when something
+	 * changes and wastes too many entries.
+	 */
+	ASSERT_LT(skel->bss->wasted_entries, 10, "check_wasted_entries");
+
+cleanup:
+	get_branch_snapshot__destroy(skel);
+	close_perf_events();
+}

tools/testing/selftests/bpf/prog_tests/module_attach.c

···
 
 static int duration;
 
-static int trigger_module_test_read(int read_sz)
-{
-	int fd, err;
-
-	fd = open("/sys/kernel/bpf_testmod", O_RDONLY);
-	err = -errno;
-	if (CHECK(fd < 0, "testmod_file_open", "failed: %d\n", err))
-		return err;
-
-	read(fd, NULL, read_sz);
-	close(fd);
-
-	return 0;
-}
-
-static int trigger_module_test_write(int write_sz)
-{
-	int fd, err;
-	char *buf = malloc(write_sz);
-
-	if (!buf)
-		return -ENOMEM;
-
-	memset(buf, 'a', write_sz);
-	buf[write_sz-1] = '\0';
-
-	fd = open("/sys/kernel/bpf_testmod", O_WRONLY);
-	err = -errno;
-	if (CHECK(fd < 0, "testmod_file_open", "failed: %d\n", err)) {
-		free(buf);
-		return err;
-	}
-
-	write(fd, buf, write_sz);
-	close(fd);
-	free(buf);
-	return 0;
-}
-
 static int delete_module(const char *name, int flags)
 {
 	return syscall(__NR_delete_module, name, flags);

tools/testing/selftests/bpf/prog_tests/skb_ctx.c

···
 		.cb[3] = 4,
 		.cb[4] = 5,
 		.priority = 6,
+		.ingress_ifindex = 11,
 		.ifindex = 1,
 		.tstamp = 7,
 		.wire_len = 100,
 		.gso_segs = 8,
 		.mark = 9,
 		.gso_size = 10,
+		.hwtstamp = 11,
 	};
 	struct bpf_prog_test_run_attr tattr = {
 		.data_in = &pkt_v4,
···
 		   "ctx_out_ifindex",
 		   "skb->ifindex == %d, expected %d\n",
 		   skb.ifindex, 1);
+	CHECK_ATTR(skb.ingress_ifindex != 11,
+		   "ctx_out_ingress_ifindex",
+		   "skb->ingress_ifindex == %d, expected %d\n",
+		   skb.ingress_ifindex, 11);
 	CHECK_ATTR(skb.tstamp != 8,
 		   "ctx_out_tstamp",
 		   "skb->tstamp == %lld, expected %d\n",

tools/testing/selftests/bpf/prog_tests/skeleton.c

···
 	struct test_skeleton__data *data;
 	struct test_skeleton__rodata *rodata;
 	struct test_skeleton__kconfig *kcfg;
+	const void *elf_bytes;
+	size_t elf_bytes_sz = 0;
 
 	skel = test_skeleton__open();
 	if (CHECK(!skel, "skel_open", "failed to open skeleton\n"))
···
 	      "got %d != exp %d\n", bss->bpf_syscall, kcfg->CONFIG_BPF_SYSCALL);
 	CHECK(bss->kern_ver != kcfg->LINUX_KERNEL_VERSION, "ext2",
 	      "got %d != exp %d\n", bss->kern_ver, kcfg->LINUX_KERNEL_VERSION);
+
+	elf_bytes = test_skeleton__elf_bytes(&elf_bytes_sz);
+	ASSERT_OK_PTR(elf_bytes, "elf_bytes");
+	ASSERT_GE(elf_bytes_sz, 0, "elf_bytes_sz");
 
 cleanup:
 	test_skeleton__destroy(skel);

tools/testing/selftests/bpf/prog_tests/tailcalls.c

···
 	bpf_object__close(obj);
 }
 
-/* test_tailcall_3 checks that the count value of the tail call limit
- * enforcement matches with expectations.
- */
-static void test_tailcall_3(void)
+static void test_tailcall_count(const char *which)
 {
 	int err, map_fd, prog_fd, main_fd, data_fd, i, val;
 	struct bpf_map *prog_array, *data_map;
···
 	__u32 retval, duration;
 	char buff[128] = {};
 
-	err = bpf_prog_load("tailcall3.o", BPF_PROG_TYPE_SCHED_CLS, &obj,
+	err = bpf_prog_load(which, BPF_PROG_TYPE_SCHED_CLS, &obj,
 			    &prog_fd);
 	if (CHECK_FAIL(err))
 		return;
···
 	      err, errno, retval);
 out:
 	bpf_object__close(obj);
+}
+
+/* test_tailcall_3 checks that the count value of the tail call limit
+ * enforcement matches with expectations. JIT uses direct jump.
+ */
+static void test_tailcall_3(void)
+{
+	test_tailcall_count("tailcall3.o");
+}
+
+/* test_tailcall_6 checks that the count value of the tail call limit
+ * enforcement matches with expectations. JIT uses indirect jump.
+ */
+static void test_tailcall_6(void)
+{
+	test_tailcall_count("tailcall6.o");
 }
 
 /* test_tailcall_4 checks that the kernel properly selects indirect jump
···
 		test_tailcall_4();
 	if (test__start_subtest("tailcall_5"))
 		test_tailcall_5();
+	if (test__start_subtest("tailcall_6"))
+		test_tailcall_6();
 	if (test__start_subtest("tailcall_bpf2bpf_1"))
 		test_tailcall_bpf2bpf_1();
 	if (test__start_subtest("tailcall_bpf2bpf_2"))

tools/testing/selftests/bpf/prog_tests/tc_redirect.c

···
 	struct nstoken *nstoken = NULL;
 	int err;
 	int tunnel_pid = -1;
-	int src_fd, target_fd;
+	int src_fd, target_fd = -1;
 	int ifindex;
 
 	/* Start a L3 TUN/TAP tunnel between the src and dst namespaces.

tools/testing/selftests/bpf/progs/bpf_cubic.c

···
 	ca->sample_cnt = 0;
 }
 
-/* "struct_ops/" prefix is not a requirement
- * It will be recognized as BPF_PROG_TYPE_STRUCT_OPS
- * as long as it is used in one of the func ptr
- * under SEC(".struct_ops").
- */
+/* "struct_ops/" prefix is a requirement */
 SEC("struct_ops/bpf_cubic_init")
 void BPF_PROG(bpf_cubic_init, struct sock *sk)
 {
···
 		tcp_sk(sk)->snd_ssthresh = initial_ssthresh;
 }
 
-/* No prefix in SEC will also work.
- * The remaining tcp-cubic functions have an easier way.
- */
-SEC("no-sec-prefix-bictcp_cwnd_event")
+/* "struct_ops" prefix is a requirement */
+SEC("struct_ops/bpf_cubic_cwnd_event")
 void BPF_PROG(bpf_cubic_cwnd_event, struct sock *sk, enum tcp_ca_event event)
 {
 	if (event == CA_EVENT_TX_START) {

tools/testing/selftests/bpf/progs/get_branch_snapshot.c

···
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2021 Facebook */
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+char _license[] SEC("license") = "GPL";
+
+__u64 test1_hits = 0;
+__u64 address_low = 0;
+__u64 address_high = 0;
+int wasted_entries = 0;
+long total_entries = 0;
+
+#define ENTRY_CNT 32
+struct perf_branch_entry entries[ENTRY_CNT] = {};
+
+static inline bool in_range(__u64 val)
+{
+	return (val >= address_low) && (val < address_high);
+}
+
+SEC("fexit/bpf_testmod_loop_test")
+int BPF_PROG(test1, int n, int ret)
+{
+	long i;
+
+	total_entries = bpf_get_branch_snapshot(entries, sizeof(entries), 0);
+	total_entries /= sizeof(struct perf_branch_entry);
+
+	for (i = 0; i < ENTRY_CNT; i++) {
+		if (i >= total_entries)
+			break;
+		if (in_range(entries[i].from) && in_range(entries[i].to))
+			test1_hits++;
+		else if (!test1_hits)
+			wasted_entries++;
+	}
+	return 0;
+}

tools/testing/selftests/bpf/progs/tag.c

···
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2021 Facebook */
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+#ifndef __has_attribute
+#define __has_attribute(x) 0
+#endif
+
+#if __has_attribute(btf_tag)
+#define __tag1 __attribute__((btf_tag("tag1")))
+#define __tag2 __attribute__((btf_tag("tag2")))
+volatile const bool skip_tests __tag1 __tag2 = false;
+#else
+#define __tag1
+#define __tag2
+volatile const bool skip_tests = true;
+#endif
+
+struct key_t {
+	int a;
+	int b __tag1 __tag2;
+	int c;
+} __tag1 __tag2;
+
+struct {
+	__uint(type, BPF_MAP_TYPE_HASH);
+	__uint(max_entries, 3);
+	__type(key, struct key_t);
+	__type(value, __u64);
+} hashmap1 SEC(".maps");
+
+
+static __noinline int foo(int x __tag1 __tag2) __tag1 __tag2
+{
+	struct key_t key;
+	__u64 val = 1;
+
+	key.a = key.b = key.c = x;
+	bpf_map_update_elem(&hashmap1, &key, &val, 0);
+	return 0;
+}
+
+SEC("fentry/bpf_fentry_test1")
+int BPF_PROG(sub, int x)
+{
+	return foo(x);
+}

tools/testing/selftests/bpf/progs/tailcall6.c

···
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+
+#include <bpf/bpf_helpers.h>
+
+struct {
+	__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
+	__uint(max_entries, 1);
+	__uint(key_size, sizeof(__u32));
+	__uint(value_size, sizeof(__u32));
+} jmp_table SEC(".maps");
+
+int count, which;
+
+SEC("classifier/0")
+int bpf_func_0(struct __sk_buff *skb)
+{
+	count++;
+	if (__builtin_constant_p(which))
+		__bpf_unreachable();
+	bpf_tail_call(skb, &jmp_table, which);
+	return 1;
+}
+
+SEC("classifier")
+int entry(struct __sk_buff *skb)
+{
+	if (__builtin_constant_p(which))
+		__bpf_unreachable();
+	bpf_tail_call(skb, &jmp_table, which);
+	return 0;
+}
+
+char __license[] SEC("license") = "GPL";

tools/testing/selftests/bpf/progs/test_skb_ctx.c

···
 		return 1;
 	if (skb->gso_size != 10)
 		return 1;
+	if (skb->ingress_ifindex != 11)
+		return 1;
+	if (skb->ifindex != 1)
+		return 1;
+	if (skb->hwtstamp != 11)
+		return 1;
 
 	return 0;
 }

tools/testing/selftests/bpf/test_btf.h

···
 #define BTF_TYPE_FLOAT_ENC(name, sz) \
 	BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_FLOAT, 0, 0), sz)
 
+#define BTF_TAG_ENC(value, type, component_idx)	\
+	BTF_TYPE_ENC(value, BTF_INFO_ENC(BTF_KIND_TAG, 0, 0), type), (component_idx)
+
 #endif /* _TEST_BTF_H */

tools/testing/selftests/bpf/test_progs.c

···
 	return chdir(flavor);
 }
 
+int trigger_module_test_read(int read_sz)
+{
+	int fd, err;
+
+	fd = open("/sys/kernel/bpf_testmod", O_RDONLY);
+	err = -errno;
+	if (!ASSERT_GE(fd, 0, "testmod_file_open"))
+		return err;
+
+	read(fd, NULL, read_sz);
+	close(fd);
+
+	return 0;
+}
+
+int trigger_module_test_write(int write_sz)
+{
+	int fd, err;
+	char *buf = malloc(write_sz);
+
+	if (!buf)
+		return -ENOMEM;
+
+	memset(buf, 'a', write_sz);
+	buf[write_sz-1] = '\0';
+
+	fd = open("/sys/kernel/bpf_testmod", O_WRONLY);
+	err = -errno;
+	if (!ASSERT_GE(fd, 0, "testmod_file_open")) {
+		free(buf);
+		return err;
+	}
+
+	write(fd, buf, write_sz);
+	close(fd);
+	free(buf);
+	return 0;
+}
+
 #define MAX_BACKTRACE_SZ 128
 void crash_handler(int signum)
 {

tools/testing/selftests/bpf/test_progs.h

···
 int compare_stack_ips(int smap_fd, int amap_fd, int stack_trace_len);
 int extract_build_id(char *build_id, size_t size);
 int kern_sync_rcu(void);
+int trigger_module_test_read(int read_sz);
+int trigger_module_test_write(int write_sz);
 
 #ifdef __x86_64__
 #define SYS_NANOSLEEP_KPROBE_NAME "__x64_sys_nanosleep"

tools/testing/selftests/bpf/trace_helpers.c

···
 // SPDX-License-Identifier: GPL-2.0
+#include <ctype.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
···
 		if (strcmp(name, sym) == 0) {
 			*addr = value;
 			goto out;
+		}
+	}
+	err = -ENOENT;
+
+out:
+	fclose(f);
+	return err;
+}
+
+/* find the address of the next symbol of the same type, this can be used
+ * to determine the end of a function.
+ */
+int kallsyms_find_next(const char *sym, unsigned long long *addr)
+{
+	char type, found_type, name[500];
+	unsigned long long value;
+	bool found = false;
+	int err = 0;
+	FILE *f;
+
+	f = fopen("/proc/kallsyms", "r");
+	if (!f)
+		return -EINVAL;
+
+	while (fscanf(f, "%llx %c %499s%*[^\n]\n", &value, &type, name) > 0) {
+		/* Different types of symbols in kernel modules are mixed
+		 * in /proc/kallsyms. Only return the next matching type.
+		 * Use tolower() for type so that 'T' matches 't'.
+		 */
+		if (found && found_type == tolower(type)) {
+			*addr = value;
+			goto out;
+		}
+		if (strcmp(name, sym) == 0) {
+			found = true;
+			found_type = tolower(type);
 		}
 	}
 	err = -ENOENT;

tools/testing/selftests/bpf/trace_helpers.h

···
 /* open kallsyms and find addresses on the fly, faster than load + search. */
 int kallsyms_find(const char *sym, unsigned long long *addr);
 
+/* find the address of the next symbol, this can be used to determine the
+ * end of a function
+ */
+int kallsyms_find_next(const char *sym, unsigned long long *addr);
+
 void read_trace_pipe(void);
 
 ssize_t get_uprobe_offset(const void *addr, ssize_t base);

tools/testing/selftests/bpf/verifier/ctx_skb.c

···
 	.prog_type = BPF_PROG_TYPE_SCHED_CLS,
 },
 {
+	"padding after gso_size is not accessible",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+		    offsetofend(struct __sk_buff, gso_size)),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = REJECT,
+	.result_unpriv = REJECT,
+	.errstr = "invalid bpf_context access off=180 size=4",
+	.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+},
+{
+	"read hwtstamp from CGROUP_SKB",
+	.insns = {
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1,
+		    offsetof(struct __sk_buff, hwtstamp)),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_CGROUP_SKB,
+},
+{
+	"read hwtstamp from CGROUP_SKB",
+	.insns = {
+	BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_1,
+		    offsetof(struct __sk_buff, hwtstamp)),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_CGROUP_SKB,
+},
+{
+	"write hwtstamp from CGROUP_SKB",
+	.insns = {
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0,
+		    offsetof(struct __sk_buff, hwtstamp)),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = REJECT,
+	.result_unpriv = REJECT,
+	.errstr = "invalid bpf_context access off=184 size=8",
+	.prog_type = BPF_PROG_TYPE_CGROUP_SKB,
+},
+{
+	"read hwtstamp from CLS",
+	.insns = {
+	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1,
+		    offsetof(struct __sk_buff, hwtstamp)),
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_SCHED_CLS,
+},
+{
 	"check wire_len is not readable by sockets",
 	.insns = {
 		BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,

tools/testing/selftests/bpf/verifier/jit.c

···
 	BPF_JMP_REG(BPF_JEQ, BPF_REG_3, BPF_REG_2, 2),
 	BPF_MOV64_IMM(BPF_REG_0, 1),
 	BPF_EXIT_INSN(),
+	BPF_LD_IMM64(BPF_REG_3, 0xfefefeULL),
+	BPF_ALU64_IMM(BPF_MUL, BPF_REG_3, 0xefefef),
+	BPF_JMP_REG(BPF_JEQ, BPF_REG_3, BPF_REG_2, 2),
+	BPF_MOV64_IMM(BPF_REG_0, 1),
+	BPF_EXIT_INSN(),
 	BPF_MOV32_REG(BPF_REG_2, BPF_REG_2),
 	BPF_LD_IMM64(BPF_REG_0, 0xfefefeULL),
 	BPF_ALU32_REG(BPF_MUL, BPF_REG_0, BPF_REG_1),
···
 	BPF_JMP_REG(BPF_JEQ, BPF_REG_3, BPF_REG_2, 2),
 	BPF_MOV64_IMM(BPF_REG_0, 1),
 	BPF_EXIT_INSN(),
+	BPF_LD_IMM64(BPF_REG_3, 0xfefefeULL),
+	BPF_ALU32_IMM(BPF_MUL, BPF_REG_3, 0xefefef),
+	BPF_JMP_REG(BPF_JEQ, BPF_REG_3, BPF_REG_2, 2),
+	BPF_MOV64_IMM(BPF_REG_0, 1),
+	BPF_EXIT_INSN(),
+	BPF_LD_IMM64(BPF_REG_0, 0xfefefeULL),
+	BPF_LD_IMM64(BPF_REG_2, 0x2ad4d4aaULL),
+	BPF_ALU32_IMM(BPF_MUL, BPF_REG_0, 0x2b),
+	BPF_JMP_REG(BPF_JEQ, BPF_REG_0, BPF_REG_2, 2),
+	BPF_MOV64_IMM(BPF_REG_0, 1),
+	BPF_EXIT_INSN(),
 	BPF_LD_IMM64(BPF_REG_0, 0x952a7bbcULL),
 	BPF_LD_IMM64(BPF_REG_1, 0xfefefeULL),
-	BPF_LD_IMM64(BPF_REG_2, 0xeeff0d413122ULL),
-	BPF_ALU32_REG(BPF_MUL, BPF_REG_2, BPF_REG_1),
-	BPF_JMP_REG(BPF_JEQ, BPF_REG_2, BPF_REG_0, 2),
+	BPF_LD_IMM64(BPF_REG_5, 0xeeff0d413122ULL),
+	BPF_ALU32_REG(BPF_MUL, BPF_REG_5, BPF_REG_1),
+	BPF_JMP_REG(BPF_JEQ, BPF_REG_5, BPF_REG_0, 2),
 	BPF_MOV64_IMM(BPF_REG_0, 1),
 	BPF_EXIT_INSN(),
 	BPF_MOV64_IMM(BPF_REG_0, 2),

tools/testing/selftests/bpf/xdpxceiver.c

···
  * Virtual Ethernet interfaces.
  *
  * For each mode, the following tests are run:
- *    a. nopoll - soft-irq processing
+ *    a. nopoll - soft-irq processing in run-to-completion mode
  *    b. poll - using poll() syscall
  *    c. Socket Teardown
  *       Create a Tx and a Rx socket, Tx from one socket, Rx on another. Destroy
···
  *       Configure sockets at indexes 0 and 1, run a traffic on queue ids 0,
  *       then remove xsk sockets from queue 0 on both veth interfaces and
  *       finally run a traffic on queues ids 1
+ *    g. unaligned mode
+ *    h. tests for invalid and corner case Tx descriptors so that the correct ones
+ *       are discarded and let through, respectively.
+ *    i. 2K frame size tests
  *
  * Total tests: 12
  *
···
 
 #define exit_with_error(error) __exit_with_error(error, __FILE__, __func__, __LINE__)
 
-#define print_ksft_result(void)\
-	(ksft_test_result_pass("PASS: %s %s %s%s%s%s\n", configured_mode ? "DRV" : "SKB",\
-			       test_type == TEST_TYPE_POLL ? "POLL" : "NOPOLL",\
-			       test_type == TEST_TYPE_TEARDOWN ? "Socket Teardown" : "",\
-			       test_type == TEST_TYPE_BIDI ? "Bi-directional Sockets" : "",\
-			       test_type == TEST_TYPE_STATS ? "Stats" : "",\
-			       test_type == TEST_TYPE_BPF_RES ? "BPF RES" : ""))
+#define mode_string(test) (test)->ifobj_tx->xdp_flags & XDP_FLAGS_SKB_MODE ? "SKB" : "DRV"
+
+#define print_ksft_result(test)						\
+	(ksft_test_result_pass("PASS: %s %s\n", mode_string(test), (test)->name))
 
 static void memset32_htonl(void *dest, u32 val, u32 size)
 {
···
 	    udp_csum(ip_hdr->saddr, ip_hdr->daddr, UDP_PKT_SIZE, IPPROTO_UDP, (u16 *)udp_hdr);
 }
 
-static void xsk_configure_umem(struct ifobject *data, void *buffer, u64 size, int idx)
+static int xsk_configure_umem(struct xsk_umem_info *umem, void *buffer, u64 size)
 {
 	struct xsk_umem_config cfg = {
 		.fill_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,
 		.comp_size = XSK_RING_CONS__DEFAULT_NUM_DESCS,
-		.frame_size = XSK_UMEM__DEFAULT_FRAME_SIZE,
-		.frame_headroom = frame_headroom,
+		.frame_size = umem->frame_size,
+		.frame_headroom = umem->frame_headroom,
 		.flags = XSK_UMEM__DEFAULT_FLAGS
 	};
-	struct xsk_umem_info *umem;
 	int ret;
 
-	umem = calloc(1, sizeof(struct xsk_umem_info));
-	if (!umem)
-		exit_with_error(errno);
+	if (umem->unaligned_mode)
+		cfg.flags |= XDP_UMEM_UNALIGNED_CHUNK_FLAG;
 
 	ret = xsk_umem__create(&umem->umem, buffer, size,
 			       &umem->fq, &umem->cq, &cfg);
 	if (ret)
-		exit_with_error(-ret);
+		return ret;
 
 	umem->buffer = buffer;
-
-	data->umem_arr[idx] = umem;
+	return 0;
 }
 
-static void xsk_populate_fill_ring(struct xsk_umem_info *umem)
-{
-	int ret, i;
-	u32 idx = 0;
-
-	ret = xsk_ring_prod__reserve(&umem->fq, XSK_RING_PROD__DEFAULT_NUM_DESCS, &idx);
-	if (ret != XSK_RING_PROD__DEFAULT_NUM_DESCS)
-		exit_with_error(-ret);
-	for (i = 0; i < XSK_RING_PROD__DEFAULT_NUM_DESCS; i++)
-		*xsk_ring_prod__fill_addr(&umem->fq, idx++) = i * XSK_UMEM__DEFAULT_FRAME_SIZE;
-	xsk_ring_prod__submit(&umem->fq, XSK_RING_PROD__DEFAULT_NUM_DESCS);
-}
-
-static int xsk_configure_socket(struct ifobject *ifobject, int idx)
+static int xsk_configure_socket(struct xsk_socket_info *xsk, struct xsk_umem_info *umem,
+				struct ifobject *ifobject, u32 qid)
 {
 	struct xsk_socket_config cfg;
-	struct xsk_socket_info *xsk;
 	struct xsk_ring_cons *rxr;
 	struct xsk_ring_prod *txr;
-	int ret;
 
-	xsk = calloc(1, sizeof(struct xsk_socket_info));
-	if (!xsk)
-		exit_with_error(errno);
-
-	xsk->umem = ifobject->umem;
-	cfg.rx_size = rxqsize;
+	xsk->umem = umem;
+	cfg.rx_size = xsk->rxqsize;
 	cfg.tx_size = XSK_RING_PROD__DEFAULT_NUM_DESCS;
 	cfg.libbpf_flags = 0;
-	cfg.xdp_flags = xdp_flags;
-	cfg.bind_flags = xdp_bind_flags;
+	cfg.xdp_flags = ifobject->xdp_flags;
+	cfg.bind_flags = ifobject->bind_flags;
 
-	if (test_type != TEST_TYPE_BIDI) {
-		rxr = (ifobject->fv.vector == rx) ? &xsk->rx : NULL;
-		txr = (ifobject->fv.vector == tx) ? &xsk->tx : NULL;
-	} else {
-		rxr = &xsk->rx;
-		txr = &xsk->tx;
-	}
-
-	ret = xsk_socket__create(&xsk->xsk, ifobject->ifname, idx,
-				 ifobject->umem->umem, rxr, txr, &cfg);
-	if (ret)
-		return 1;
-
-	ifobject->xsk_arr[idx] = xsk;
-
-	return 0;
+	txr = ifobject->tx_on ? &xsk->tx : NULL;
+	rxr = ifobject->rx_on ? &xsk->rx : NULL;
+	return xsk_socket__create(&xsk->xsk, ifobject->ifname, qid, umem->umem, rxr, txr, &cfg);
 }
 
 static struct option long_options[] = {
···
 	return nsfd;
 }
 
-static int validate_interfaces(void)
+static bool validate_interface(struct ifobject *ifobj)
 {
-	bool ret = true;
-
-	for (int i = 0; i < MAX_INTERFACES; i++) {
-		if (!strcmp(ifdict[i]->ifname, "")) {
-			ret = false;
-			ksft_test_result_fail("ERROR: interfaces: -i <int>,<ns> -i <int>,<ns>.");
-		}
-	}
-	return ret;
+	if (!strcmp(ifobj->ifname, ""))
+		return false;
+	return true;
 }
 
-static void parse_command_line(int argc, char **argv)
+static void parse_command_line(struct ifobject *ifobj_tx, struct ifobject *ifobj_rx, int argc,
+			       char **argv)
 {
-	int option_index, interface_index = 0, c;
+	struct ifobject *ifobj;
+	u32 interface_nb = 0;
+	int option_index, c;
 
 	opterr = 0;
 
 	for (;;) {
-		c = getopt_long(argc, argv, "i:Dv", long_options, &option_index);
+		char *sptr, *token;
 
+		c = getopt_long(argc, argv, "i:Dv", long_options, &option_index);
 		if (c == -1)
 			break;
 
 		switch (c) {
 		case 'i':
-			if (interface_index == MAX_INTERFACES)
+			if (interface_nb == 0)
+				ifobj = ifobj_tx;
+			else if (interface_nb == 1)
+				ifobj = ifobj_rx;
+			else
 				break;
-			char *sptr, *token;
 
 			sptr = strndupa(optarg, strlen(optarg));
-			memcpy(ifdict[interface_index]->ifname,
-			       strsep(&sptr, ","), MAX_INTERFACE_NAME_CHARS);
+			memcpy(ifobj->ifname, strsep(&sptr, ","), MAX_INTERFACE_NAME_CHARS);
 			token = strsep(&sptr, ",");
 			if (token)
-				memcpy(ifdict[interface_index]->nsname, token,
-				       MAX_INTERFACES_NAMESPACE_CHARS);
-			interface_index++;
+				memcpy(ifobj->nsname, token, MAX_INTERFACES_NAMESPACE_CHARS);
+			interface_nb++;
 			break;
 		case 'D':
 			opt_pkt_dump = true;
···
 			ksft_exit_xfail();
 		}
 	}
+}
 
-	if (!validate_interfaces()) {
-		usage(basename(argv[0]));
-		ksft_exit_xfail();
+static void __test_spec_init(struct test_spec *test, struct ifobject *ifobj_tx,
+			     struct ifobject *ifobj_rx)
+{
+	u32 i, j;
+
+	for (i = 0; i < MAX_INTERFACES; i++) {
+		struct ifobject *ifobj = i ? ifobj_rx : ifobj_tx;
+
+		ifobj->umem = &ifobj->umem_arr[0];
+		ifobj->xsk = &ifobj->xsk_arr[0];
+		ifobj->use_poll = false;
+		ifobj->pkt_stream = test->pkt_stream_default;
+
+		if (i == 0) {
+			ifobj->rx_on = false;
+			ifobj->tx_on = true;
+		} else {
+			ifobj->rx_on = true;
+			ifobj->tx_on = false;
+		}
+
+		for (j = 0; j < MAX_SOCKETS; j++) {
+			memset(&ifobj->umem_arr[j], 0, sizeof(ifobj->umem_arr[j]));
+			memset(&ifobj->xsk_arr[j], 0, sizeof(ifobj->xsk_arr[j]));
+			ifobj->umem_arr[j].num_frames = DEFAULT_UMEM_BUFFERS;
+			ifobj->umem_arr[j].frame_size = XSK_UMEM__DEFAULT_FRAME_SIZE;
+			ifobj->xsk_arr[j].rxqsize = XSK_RING_CONS__DEFAULT_NUM_DESCS;
+		}
 	}
+
+	test->ifobj_tx = ifobj_tx;
+	test->ifobj_rx = ifobj_rx;
+	test->current_step = 0;
+	test->total_steps = 1;
+	test->nb_sockets = 1;
+}
+
+static void test_spec_init(struct test_spec *test, struct ifobject *ifobj_tx,
+			   struct ifobject *ifobj_rx, enum test_mode mode)
+{
+	struct pkt_stream *pkt_stream;
+	u32 i;
+
+	pkt_stream = test->pkt_stream_default;
+	memset(test, 0, sizeof(*test));
+	test->pkt_stream_default = pkt_stream;
+
+	for (i = 0; i < MAX_INTERFACES; i++) {
+		struct ifobject *ifobj = i ? ifobj_rx : ifobj_tx;
+
+		ifobj->xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
+		if (mode == TEST_MODE_SKB)
+			ifobj->xdp_flags |= XDP_FLAGS_SKB_MODE;
+		else
+			ifobj->xdp_flags |= XDP_FLAGS_DRV_MODE;
+
+		ifobj->bind_flags = XDP_USE_NEED_WAKEUP | XDP_COPY;
+	}
+
+	__test_spec_init(test, ifobj_tx, ifobj_rx);
+}
+
+static void test_spec_reset(struct test_spec *test)
+{
+	__test_spec_init(test, test->ifobj_tx, test->ifobj_rx);
+}
+
+static void test_spec_set_name(struct test_spec *test, const char *name)
+{
+	strncpy(test->name, name, MAX_TEST_NAME_SIZE);
 }
 
 static struct pkt *pkt_stream_get_pkt(struct pkt_stream *pkt_stream, u32 pkt_nb)
···
 	return &pkt_stream->pkts[pkt_nb];
 }
 
-static struct pkt_stream *pkt_stream_generate(u32 nb_pkts, u32 pkt_len)
+static struct pkt *pkt_stream_get_next_rx_pkt(struct pkt_stream *pkt_stream)
+{
+	while (pkt_stream->rx_pkt_nb < pkt_stream->nb_pkts) {
+		if (pkt_stream->pkts[pkt_stream->rx_pkt_nb].valid)
+			return &pkt_stream->pkts[pkt_stream->rx_pkt_nb++];
+		pkt_stream->rx_pkt_nb++;
+	}
+	return NULL;
+}
+
+static void pkt_stream_delete(struct pkt_stream *pkt_stream)
+{
+	free(pkt_stream->pkts);
+	free(pkt_stream);
+}
+
+static void pkt_stream_restore_default(struct test_spec *test)
+{
+	if (test->ifobj_tx->pkt_stream != test->pkt_stream_default) {
+		pkt_stream_delete(test->ifobj_tx->pkt_stream);
+		test->ifobj_tx->pkt_stream = test->pkt_stream_default;
+	}
+	test->ifobj_rx->pkt_stream = test->pkt_stream_default;
+}
+
+static struct pkt_stream *__pkt_stream_alloc(u32 nb_pkts)
+{
+	struct pkt_stream *pkt_stream;
+
+	pkt_stream = calloc(1, sizeof(*pkt_stream));
+	if (!pkt_stream)
+		return NULL;
+
+	pkt_stream->pkts = calloc(nb_pkts, sizeof(*pkt_stream->pkts));
+	if (!pkt_stream->pkts) {
+		free(pkt_stream);
+		return NULL;
+	}
+
+	pkt_stream->nb_pkts = nb_pkts;
+	return pkt_stream;
+}
+
+static struct pkt_stream *pkt_stream_generate(struct xsk_umem_info *umem, u32 nb_pkts, u32 pkt_len)
 {
 	struct pkt_stream *pkt_stream;
 	u32 i;
 
-	pkt_stream = malloc(sizeof(*pkt_stream));
+	pkt_stream = __pkt_stream_alloc(nb_pkts);
 	if (!pkt_stream)
-		exit_with_error(ENOMEM);
-
-	pkt_stream->pkts = calloc(nb_pkts, sizeof(*pkt_stream->pkts));
-	if (!pkt_stream->pkts)
 		exit_with_error(ENOMEM);
 
 	pkt_stream->nb_pkts = nb_pkts;
 	for (i = 0; i < nb_pkts; i++) {
-		pkt_stream->pkts[i].addr = (i % num_frames) * XSK_UMEM__DEFAULT_FRAME_SIZE;
+		pkt_stream->pkts[i].addr = (i % umem->num_frames) * umem->frame_size +
+			DEFAULT_OFFSET;
 		pkt_stream->pkts[i].len = pkt_len;
 		pkt_stream->pkts[i].payload = i;
+
+		if (pkt_len > umem->frame_size)
+			pkt_stream->pkts[i].valid = false;
+		else
+			pkt_stream->pkts[i].valid = true;
 	}
 
 	return pkt_stream;
+}
+
+static struct pkt_stream *pkt_stream_clone(struct xsk_umem_info *umem,
+					   struct pkt_stream *pkt_stream)
+{
+	return pkt_stream_generate(umem, pkt_stream->nb_pkts, pkt_stream->pkts[0].len);
+}
+
+static void pkt_stream_replace(struct test_spec *test, u32 nb_pkts, u32 pkt_len)
+{
+	struct pkt_stream *pkt_stream;
+
+	pkt_stream = pkt_stream_generate(test->ifobj_tx->umem, nb_pkts, pkt_len);
+	test->ifobj_tx->pkt_stream = pkt_stream;
+	test->ifobj_rx->pkt_stream = pkt_stream;
+}
+
+static void pkt_stream_replace_half(struct test_spec *test, u32 pkt_len, u32 offset)
+{
+	struct xsk_umem_info *umem = test->ifobj_tx->umem;
+	struct pkt_stream *pkt_stream;
+	u32 i;
+
+	pkt_stream = pkt_stream_clone(umem, test->pkt_stream_default);
+	for (i = 0; i < test->pkt_stream_default->nb_pkts; i += 2) {
+		pkt_stream->pkts[i].addr = (i % umem->num_frames) * umem->frame_size + offset;
+		pkt_stream->pkts[i].len = pkt_len;
+	}
+
+	test->ifobj_tx->pkt_stream = pkt_stream;
+	test->ifobj_rx->pkt_stream = pkt_stream;
 }
 
 static struct pkt *pkt_generate(struct ifobject *ifobject, u32 pkt_nb)
···
 
 	if (!pkt)
 		return NULL;
+	if (!pkt->valid || pkt->len < PKT_SIZE)
+		return pkt;
 
 	data = xsk_umem__get_data(ifobject->umem->buffer, pkt->addr);
 	udp_hdr = (struct udphdr *)(data + sizeof(struct ethhdr) + sizeof(struct iphdr));
···
 	gen_eth_hdr(ifobject, eth_hdr);
 
 	return pkt;
+}
+
+static void pkt_stream_generate_custom(struct test_spec *test, struct pkt *pkts, u32 nb_pkts)
+{
+	struct pkt_stream *pkt_stream;
+	u32 i;
+
+	pkt_stream = __pkt_stream_alloc(nb_pkts);
+	if (!pkt_stream)
+		exit_with_error(ENOMEM);
+
+	test->ifobj_tx->pkt_stream = pkt_stream;
+	test->ifobj_rx->pkt_stream = pkt_stream;
+
+	for (i = 0; i < nb_pkts; i++) {
+		pkt_stream->pkts[i].addr = pkts[i].addr;
+		pkt_stream->pkts[i].len = pkts[i].len;
+		pkt_stream->pkts[i].payload = i;
+		pkt_stream->pkts[i].valid = pkts[i].valid;
+	}
 }
 
 static void pkt_dump(void *pkt, u32 len)
···
 	fprintf(stdout, "---------------------------------------\n");
 }
 
-static bool is_pkt_valid(struct pkt *pkt, void *buffer, const struct xdp_desc *desc)
+static bool is_pkt_valid(struct pkt *pkt, void *buffer, u64 addr, u32 len)
 {
-	void *data = xsk_umem__get_data(buffer, desc->addr);
+	void *data = xsk_umem__get_data(buffer, addr);
 	struct iphdr *iphdr = (struct iphdr *)(data + sizeof(struct ethhdr));
 
 	if (!pkt) {
···
 		return false;
 	}
 
+	if (len < PKT_SIZE) {
+		/*Do not try to verify packets that are smaller than minimum size. */
+		return true;
+	}
+
+	if (pkt->len != len) {
+		ksft_test_result_fail
+			("ERROR: [%s] expected length [%d], got length [%d]\n",
+			 __func__, pkt->len, len);
+		return false;
+	}
+
 	if (iphdr->version == IP_PKT_VER && iphdr->tos == IP_PKT_TOS) {
 		u32 seqnum = ntohl(*((u32 *)(data + PKT_HDR_SIZE)));
 
-		if (opt_pkt_dump && test_type != TEST_TYPE_STATS)
+		if (opt_pkt_dump)
 			pkt_dump(data, PKT_SIZE);
-
-		if (pkt->len != desc->len) {
-			ksft_test_result_fail
-				("ERROR: [%s] expected length [%d], got length [%d]\n",
-					__func__, pkt->len, desc->len);
-			return false;
-		}
 
 		if (pkt->payload != seqnum) {
 			ksft_test_result_fail
···
 	unsigned int rcvd;
 	u32 idx;
 
-	if (!xsk->outstanding_tx)
-		return;
-
 	if (xsk_ring_prod__needs_wakeup(&xsk->tx))
 		kick_tx(xsk);
 
 	rcvd = xsk_ring_cons__peek(&xsk->umem->cq, batch_size, &idx);
 	if (rcvd) {
+		if (rcvd > xsk->outstanding_tx) {
+			u64 addr = *xsk_ring_cons__comp_addr(&xsk->umem->cq, idx + rcvd - 1);
+
+			ksft_test_result_fail("ERROR: [%s] Too many packets completed\n",
+					      __func__);
+			ksft_print_msg("Last completion address: %llx\n", addr);
+			return;
+		}
+
 		xsk_ring_cons__release(&xsk->umem->cq, rcvd);
 		xsk->outstanding_tx -= rcvd;
 	}
···
 static void receive_pkts(struct pkt_stream *pkt_stream, struct xsk_socket_info *xsk,
 			 struct pollfd *fds)
 {
-	u32 idx_rx = 0, idx_fq = 0, rcvd, i, pkt_count = 0;
-	struct pkt *pkt;
+	struct pkt *pkt = pkt_stream_get_next_rx_pkt(pkt_stream);
+	u32 idx_rx = 0, idx_fq = 0, rcvd, i;
 	int ret;
 
-	pkt = pkt_stream_get_pkt(pkt_stream, pkt_count++);
 	while (pkt) {
 		rcvd = xsk_ring_cons__peek(&xsk->rx, BATCH_SIZE, &idx_rx);
 		if (!rcvd) {
···
 			const struct xdp_desc *desc = xsk_ring_cons__rx_desc(&xsk->rx, idx_rx++);
 			u64 addr = desc->addr, orig;
 
+			if (!pkt) {
+				ksft_test_result_fail("ERROR: [%s] Received too many packets.\n",
+						      __func__);
+				ksft_print_msg("Last packet has addr: %llx len: %u\n",
+					       addr, desc->len);
+				return;
+			}
+
 			orig = xsk_umem__extract_addr(addr);
 			addr = xsk_umem__add_offset_to_addr(addr);
-			if (!is_pkt_valid(pkt, xsk->umem->buffer, desc))
+			if (!is_pkt_valid(pkt, xsk->umem->buffer, addr, desc->len))
 				return;
 
 			*xsk_ring_prod__fill_addr(&xsk->umem->fq, idx_fq++) = orig;
-			pkt = pkt_stream_get_pkt(pkt_stream, pkt_count++);
+			pkt = pkt_stream_get_next_rx_pkt(pkt_stream);
 		}
 
 		xsk_ring_prod__submit(&xsk->umem->fq, rcvd);
···
 static u32 __send_pkts(struct ifobject *ifobject, u32 pkt_nb)
 {
 	struct xsk_socket_info *xsk = ifobject->xsk;
-	u32 i, idx;
+	u32 i, idx, valid_pkts = 0;
 
 	while (xsk_ring_prod__reserve(&xsk->tx, BATCH_SIZE, &idx) < BATCH_SIZE)
 		complete_pkts(xsk, BATCH_SIZE);
···
 		tx_desc->addr = pkt->addr;
 		tx_desc->len = pkt->len;
 		pkt_nb++;
+		if (pkt->valid)
+			valid_pkts++;
 	}
 
 	xsk_ring_prod__submit(&xsk->tx, i);
-	if (stat_test_type != STAT_TEST_TX_INVALID)
-		xsk->outstanding_tx += i;
-	else if (xsk_ring_prod__needs_wakeup(&xsk->tx))
-		kick_tx(xsk);
-	complete_pkts(xsk, i);
+	xsk->outstanding_tx += valid_pkts;
+	complete_pkts(xsk, BATCH_SIZE);
 
 	return i;
 }
···
 
 static void send_pkts(struct ifobject *ifobject)
 {
-	struct pollfd fds[MAX_SOCKS] = { };
+	struct pollfd fds = { };
 	u32 pkt_cnt = 0;
 
-	fds[0].fd = xsk_socket__fd(ifobject->xsk->xsk);
-	fds[0].events = POLLOUT;
+	fds.fd = xsk_socket__fd(ifobject->xsk->xsk);
+	fds.events = POLLOUT;
 
 	while (pkt_cnt < ifobject->pkt_stream->nb_pkts) {
 		u32 sent;
 
-		if (test_type == TEST_TYPE_POLL) {
+		if (ifobject->use_poll) {
 			int ret;
 
-			ret = poll(fds, 1, POLL_TMOUT);
+			ret = poll(&fds, 1, POLL_TMOUT);
 			if (ret <= 0)
 				continue;
 
-			if (!(fds[0].revents & POLLOUT))
+			if (!(fds.revents & POLLOUT))
 				continue;
 		}
 
···
 	optlen = sizeof(stats);
 	err = getsockopt(fd, SOL_XDP, XDP_STATISTICS, &stats, &optlen);
 	if (err) {
-		ksft_test_result_fail("ERROR: [%s] getsockopt(XDP_STATISTICS) error %u %s\n",
+		ksft_test_result_fail("ERROR Rx: [%s] getsockopt(XDP_STATISTICS) error %u %s\n",
 				      __func__, -err, strerror(-err));
 		return true;
 	}
···
 	optlen = sizeof(stats);
 	err = getsockopt(fd, SOL_XDP, XDP_STATISTICS, &stats, &optlen);
 	if (err) {
-		ksft_test_result_fail("ERROR: [%s] getsockopt(XDP_STATISTICS) error %u %s\n",
+		ksft_test_result_fail("ERROR Tx: [%s] getsockopt(XDP_STATISTICS) error %u %s\n",
 				      __func__, -err, strerror(-err));
 		return;
 	}
···
 			      __func__, stats.tx_invalid_descs, ifobject->pkt_stream->nb_pkts);
 }
 
-static void thread_common_ops(struct ifobject *ifobject, void *bufs)
+static void thread_common_ops(struct test_spec *test, struct ifobject *ifobject)
 {
-	u64 umem_sz = num_frames * XSK_UMEM__DEFAULT_FRAME_SIZE;
 	int mmap_flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE;
-	size_t mmap_sz = umem_sz;
-	int ctr = 0;
-	int ret;
+	u32 i;
 
 	ifobject->ns_fd = switch_namespace(ifobject->nsname);
 
-	if (test_type == TEST_TYPE_BPF_RES)
-		mmap_sz *= 2;
+	if (ifobject->umem->unaligned_mode)
+		mmap_flags |= MAP_HUGETLB;
 
-	bufs = mmap(NULL, mmap_sz, PROT_READ | PROT_WRITE, mmap_flags, -1, 0);
-	if (bufs == MAP_FAILED)
-		exit_with_error(errno);
+	for (i = 0; i < test->nb_sockets; i++) {
+		u64 umem_sz = ifobject->umem->num_frames * ifobject->umem->frame_size;
+		u32 ctr = 0;
+		void *bufs;
 
-	while (ctr++ < SOCK_RECONF_CTR) {
-		xsk_configure_umem(ifobject, bufs, umem_sz, 0);
-		ifobject->umem = ifobject->umem_arr[0];
-		ret = xsk_configure_socket(ifobject, 0);
-		if (!ret)
-			break;
+		bufs = mmap(NULL, umem_sz, PROT_READ | PROT_WRITE, mmap_flags, -1, 0);
+		if (bufs == MAP_FAILED)
+			exit_with_error(errno);
 
-		/* Retry Create Socket if it fails as xsk_socket__create() is asynchronous */
-		usleep(USLEEP_MAX);
-		if (ctr >= SOCK_RECONF_CTR)
-			exit_with_error(-ret);
+		while (ctr++ < SOCK_RECONF_CTR) {
+			int ret;
+
+			ret = xsk_configure_umem(&ifobject->umem_arr[i], bufs, umem_sz);
+			if (ret)
+				exit_with_error(-ret);
+
+			ret = xsk_configure_socket(&ifobject->xsk_arr[i], &ifobject->umem_arr[i],
+						   ifobject, i);
+			if (!ret)
+				break;
+
+			/* Retry if it fails as xsk_socket__create() is asynchronous */
+			if (ctr >= SOCK_RECONF_CTR)
+				exit_with_error(-ret);
+			usleep(USLEEP_MAX);
+		}
 	}
 
-	ifobject->umem = ifobject->umem_arr[0];
-	ifobject->xsk = ifobject->xsk_arr[0];
-
-	if (test_type == TEST_TYPE_BPF_RES) {
-		xsk_configure_umem(ifobject, (u8 *)bufs + umem_sz, umem_sz, 1);
-		ifobject->umem = ifobject->umem_arr[1];
-		ret = xsk_configure_socket(ifobject, 1);
-	}
-
-	ifobject->umem = ifobject->umem_arr[0];
-	ifobject->xsk = ifobject->xsk_arr[0];
-	print_verbose("Interface [%s] vector [%s]\n",
-		      ifobject->ifname, ifobject->fv.vector == tx ? "Tx" : "Rx");
-}
-
-static bool testapp_is_test_two_stepped(void)
-{
-	return (test_type != TEST_TYPE_BIDI && test_type != TEST_TYPE_BPF_RES) || second_step;
+	ifobject->umem = &ifobject->umem_arr[0];
+	ifobject->xsk = &ifobject->xsk_arr[0];
 }
 
 static void testapp_cleanup_xsk_res(struct ifobject *ifobj)
 {
-	if (testapp_is_test_two_stepped()) {
-		xsk_socket__delete(ifobj->xsk->xsk);
-		(void)xsk_umem__delete(ifobj->umem->umem);
-	}
+	print_verbose("Destroying socket\n");
+	xsk_socket__delete(ifobj->xsk->xsk);
+	munmap(ifobj->umem->buffer, ifobj->umem->num_frames * ifobj->umem->frame_size);
+	xsk_umem__delete(ifobj->umem->umem);
 }
 
 static void *worker_testapp_validate_tx(void *arg)
 {
-	struct ifobject *ifobject = (struct ifobject *)arg;
-	void *bufs = NULL;
+	struct test_spec *test = (struct test_spec *)arg;
+	struct ifobject *ifobject = test->ifobj_tx;
 
-	if (!second_step)
-		thread_common_ops(ifobject, bufs);
+	if (test->current_step == 1)
+		thread_common_ops(test, ifobject);
 
 	print_verbose("Sending %d packets on interface %s\n", ifobject->pkt_stream->nb_pkts,
 		      ifobject->ifname);
···
 	if (stat_test_type == STAT_TEST_TX_INVALID)
 		tx_stats_validate(ifobject);
 
-	testapp_cleanup_xsk_res(ifobject);
+	if (test->total_steps == test->current_step)
+		testapp_cleanup_xsk_res(ifobject);
 	pthread_exit(NULL);
+}
+
+static void xsk_populate_fill_ring(struct xsk_umem_info *umem, struct pkt_stream *pkt_stream)
+{
+	u32 idx = 0, i;
+	int ret;
+
+	ret = xsk_ring_prod__reserve(&umem->fq, XSK_RING_PROD__DEFAULT_NUM_DESCS, &idx);
+	if (ret != XSK_RING_PROD__DEFAULT_NUM_DESCS)
+		exit_with_error(ENOSPC);
+	for (i = 0; i < XSK_RING_PROD__DEFAULT_NUM_DESCS; i++) {
+		u64 addr;
+
+		if (pkt_stream->use_addr_for_fill) {
+			struct pkt *pkt = pkt_stream_get_pkt(pkt_stream, i);
+
+			if (!pkt)
+				break;
+			addr = pkt->addr;
+		} else {
+			addr = (i % umem->num_frames) * umem->frame_size + DEFAULT_OFFSET;
+		}
+
+		*xsk_ring_prod__fill_addr(&umem->fq, idx++) = addr;
+	}
+	xsk_ring_prod__submit(&umem->fq, XSK_RING_PROD__DEFAULT_NUM_DESCS);
 }
 
 static void *worker_testapp_validate_rx(void *arg)
 {
-	struct ifobject *ifobject = (struct ifobject *)arg;
-	struct pollfd fds[MAX_SOCKS] = { };
-	void *bufs = NULL;
+	struct test_spec *test = (struct test_spec *)arg;
+	struct ifobject *ifobject = test->ifobj_rx;
+	struct pollfd fds = { };
 
-	if (!second_step)
-		thread_common_ops(ifobject, bufs);
+	if (test->current_step == 1)
+		thread_common_ops(test, ifobject);
 
-	if (stat_test_type != STAT_TEST_RX_FILL_EMPTY)
-		xsk_populate_fill_ring(ifobject->umem);
+	xsk_populate_fill_ring(ifobject->umem, ifobject->pkt_stream);
 
-	fds[0].fd = xsk_socket__fd(ifobject->xsk->xsk);
-	fds[0].events = POLLIN;
+	fds.fd = xsk_socket__fd(ifobject->xsk->xsk);
+	fds.events = POLLIN;
 
 	pthread_barrier_wait(&barr);
 
···
 		while (!rx_stats_are_valid(ifobject))
 			continue;
 	else
-		receive_pkts(ifobject->pkt_stream, ifobject->xsk, fds);
+		receive_pkts(ifobject->pkt_stream, ifobject->xsk, &fds);
 
-	if (test_type == TEST_TYPE_TEARDOWN)
-		print_verbose("Destroying socket\n");
-
-	testapp_cleanup_xsk_res(ifobject);
+	if (test->total_steps == test->current_step)
+		testapp_cleanup_xsk_res(ifobject);
 	pthread_exit(NULL);
 }
 
-static void testapp_validate(void)
+static void testapp_validate_traffic(struct test_spec *test)
 {
-	bool bidi = test_type == TEST_TYPE_BIDI;
-	bool bpf = test_type == TEST_TYPE_BPF_RES;
-	struct pkt_stream *pkt_stream;
+	struct ifobject *ifobj_tx = test->ifobj_tx;
+	struct ifobject *ifobj_rx = test->ifobj_rx;
+	pthread_t t0, t1;
 
 	if (pthread_barrier_init(&barr, NULL, 2))
 		exit_with_error(errno);
 
-	if (stat_test_type == STAT_TEST_TX_INVALID)
-		pkt_stream = pkt_stream_generate(DEFAULT_PKT_CNT, XSK_UMEM__INVALID_FRAME_SIZE);
-	else
-		pkt_stream = pkt_stream_generate(DEFAULT_PKT_CNT, PKT_SIZE);
-	ifdict_tx->pkt_stream = pkt_stream;
-	ifdict_rx->pkt_stream = pkt_stream;
+	test->current_step++;
 
 	/*Spawn RX thread */
-	pthread_create(&t0, NULL, ifdict_rx->func_ptr, ifdict_rx);
+	pthread_create(&t0, NULL, ifobj_rx->func_ptr, test);
 
 	pthread_barrier_wait(&barr);
 	if (pthread_barrier_destroy(&barr))
 		exit_with_error(errno);
 
 	/*Spawn TX thread */
-	pthread_create(&t1, NULL, ifdict_tx->func_ptr, ifdict_tx);
+	pthread_create(&t1, NULL, ifobj_tx->func_ptr, test);
 
 	pthread_join(t1, NULL);
 	pthread_join(t0, NULL);
-
-	if (!(test_type == TEST_TYPE_TEARDOWN) && !bidi && !bpf && !(test_type == TEST_TYPE_STATS))
-		print_ksft_result();
 }
 
-static void testapp_teardown(void)
+static void testapp_teardown(struct test_spec *test)
 {
 	int i;
 
+	test_spec_set_name(test, "TEARDOWN");
 	for (i = 0; i < MAX_TEARDOWN_ITER; i++) {
-		print_verbose("Creating socket\n");
-		testapp_validate();
+		testapp_validate_traffic(test);
+		test_spec_reset(test);
 	}
-
-	print_ksft_result();
 }
 
-static void swap_vectors(struct ifobject *ifobj1, struct ifobject *ifobj2)
+static void swap_directions(struct ifobject **ifobj1, struct ifobject **ifobj2)
 {
-	void *(*tmp_func_ptr)(void *) = ifobj1->func_ptr;
-	enum fvector tmp_vector = ifobj1->fv.vector;
+	thread_func_t tmp_func_ptr = (*ifobj1)->func_ptr;
+	struct ifobject *tmp_ifobj = (*ifobj1);
 
-	ifobj1->func_ptr = ifobj2->func_ptr;
-	ifobj1->fv.vector = ifobj2->fv.vector;
+	(*ifobj1)->func_ptr = (*ifobj2)->func_ptr;
+	(*ifobj2)->func_ptr = tmp_func_ptr;
 
-	ifobj2->func_ptr = tmp_func_ptr;
-	ifobj2->fv.vector = tmp_vector;
-
-	ifdict_tx = ifobj1;
-	ifdict_rx = ifobj2;
+	*ifobj1 = *ifobj2;
+	*ifobj2 = tmp_ifobj;
 }
 
-static void testapp_bidi(void)
+static void testapp_bidi(struct test_spec *test)
 {
-	for (int i = 0; i < MAX_BIDI_ITER; i++) {
-		print_verbose("Creating socket\n");
-		testapp_validate();
-		if (!second_step) {
-			print_verbose("Switching Tx/Rx vectors\n");
-			swap_vectors(ifdict[1], ifdict[0]);
-		}
-		second_step = true;
-	}
+	test_spec_set_name(test, "BIDIRECTIONAL");
+	test->ifobj_tx->rx_on = true;
+	test->ifobj_rx->tx_on = true;
+	test->total_steps = 2;
+	testapp_validate_traffic(test);
 
-	swap_vectors(ifdict[0], ifdict[1]);
+	print_verbose("Switching Tx/Rx vectors\n");
+	swap_directions(&test->ifobj_rx, &test->ifobj_tx);
+	testapp_validate_traffic(test);
 
-	print_ksft_result();
+	swap_directions(&test->ifobj_rx, &test->ifobj_tx);
 }
 
-static void swap_xsk_res(void)
+static void swap_xsk_resources(struct ifobject *ifobj_tx, struct ifobject *ifobj_rx)
 {
-	xsk_socket__delete(ifdict_tx->xsk->xsk);
-	xsk_umem__delete(ifdict_tx->umem->umem);
-	xsk_socket__delete(ifdict_rx->xsk->xsk);
-	xsk_umem__delete(ifdict_rx->umem->umem);
-	ifdict_tx->umem = ifdict_tx->umem_arr[1];
-	ifdict_tx->xsk = ifdict_tx->xsk_arr[1];
-	ifdict_rx->umem = ifdict_rx->umem_arr[1];
-	ifdict_rx->xsk = ifdict_rx->xsk_arr[1];
+	xsk_socket__delete(ifobj_tx->xsk->xsk);
+	xsk_umem__delete(ifobj_tx->umem->umem);
+	xsk_socket__delete(ifobj_rx->xsk->xsk);
+	xsk_umem__delete(ifobj_rx->umem->umem);
+	ifobj_tx->umem = &ifobj_tx->umem_arr[1];
+	ifobj_tx->xsk = &ifobj_tx->xsk_arr[1];
+	ifobj_rx->umem = &ifobj_rx->umem_arr[1];
+	ifobj_rx->xsk = &ifobj_rx->xsk_arr[1];
 }
 
-static void testapp_bpf_res(void)
+static void testapp_bpf_res(struct test_spec *test)
+{
+	test_spec_set_name(test, "BPF_RES");
+	test->total_steps = 2;
+	test->nb_sockets = 2;
+	testapp_validate_traffic(test);
+
+	swap_xsk_resources(test->ifobj_tx, test->ifobj_rx);
+	testapp_validate_traffic(test);
+}
+
+static void testapp_stats(struct test_spec *test)
 {
 	int i;
 
-	for (i = 0; i < MAX_BPF_ITER; i++) {
-		print_verbose("Creating socket\n");
-		testapp_validate();
-		if (!second_step)
-			swap_xsk_res();
-		second_step = true;
-	}
-
-	print_ksft_result();
-}
-
-static void testapp_stats(void)
-{
-	for (int i = 0; i < STAT_TEST_TYPE_MAX; i++) {
+	for (i = 0; i < STAT_TEST_TYPE_MAX; i++) {
+		test_spec_reset(test);
 		stat_test_type = i;
-
-		/* reset defaults */
-		rxqsize = XSK_RING_CONS__DEFAULT_NUM_DESCS;
-		frame_headroom = XSK_UMEM__DEFAULT_FRAME_HEADROOM;
 
 		switch (stat_test_type) {
 		case STAT_TEST_RX_DROPPED:
-			frame_headroom = XSK_UMEM__DEFAULT_FRAME_SIZE -
-						XDP_PACKET_HEADROOM - 1;
+			test_spec_set_name(test, "STAT_RX_DROPPED");
+			test->ifobj_rx->umem->frame_headroom = test->ifobj_rx->umem->frame_size -
+				XDP_PACKET_HEADROOM - 1;
+			testapp_validate_traffic(test);
 			break;
 		case STAT_TEST_RX_FULL:
-			rxqsize = RX_FULL_RXQSIZE;
+			test_spec_set_name(test, "STAT_RX_FULL");
+			test->ifobj_rx->xsk->rxqsize = RX_FULL_RXQSIZE;
+			testapp_validate_traffic(test);
 			break;
 		case STAT_TEST_TX_INVALID:
-			continue;
+			test_spec_set_name(test, "STAT_TX_INVALID");
+			pkt_stream_replace(test, DEFAULT_PKT_CNT, XSK_UMEM__INVALID_FRAME_SIZE);
+			testapp_validate_traffic(test);
+
+			pkt_stream_restore_default(test);
+			break;
+		case STAT_TEST_RX_FILL_EMPTY:
+			test_spec_set_name(test, "STAT_RX_FILL_EMPTY");
+			test->ifobj_rx->pkt_stream = pkt_stream_generate(test->ifobj_rx->umem, 0,
+									 MIN_PKT_SIZE);
+			if (!test->ifobj_rx->pkt_stream)
+				exit_with_error(ENOMEM);
+			test->ifobj_rx->pkt_stream->use_addr_for_fill = true;
+			testapp_validate_traffic(test);
+
+			pkt_stream_restore_default(test);
+			break;
 		default:
 			break;
 		}
-		testapp_validate();
 	}
 
-	print_ksft_result();
+	/* To only see the whole stat set being completed unless an individual test fails. */
+	test_spec_set_name(test, "STATS");
 }
 
-static void init_iface(struct ifobject *ifobj, const char *dst_mac,
-		       const char *src_mac, const char *dst_ip,
-		       const char *src_ip, const u16 dst_port,
-		       const u16 src_port, enum fvector vector)
+/* Simple test */
+static bool hugepages_present(struct ifobject *ifobject)
+{
+	const size_t mmap_sz = 2 * ifobject->umem->num_frames * ifobject->umem->frame_size;
+	void *bufs;
+
+	bufs = mmap(NULL, mmap_sz, PROT_READ | PROT_WRITE,
+		    MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE | MAP_HUGETLB, -1, 0);
+	if (bufs == MAP_FAILED)
+		return false;
+
+	munmap(bufs, mmap_sz);
+	return true;
+}
+
+static bool testapp_unaligned(struct test_spec *test)
+{
+	if (!hugepages_present(test->ifobj_tx)) {
+		ksft_test_result_skip("No 2M huge pages present.\n");
+		return false;
+	}
+
+	test_spec_set_name(test, "UNALIGNED_MODE");
+	test->ifobj_tx->umem->unaligned_mode = true;
+	test->ifobj_rx->umem->unaligned_mode = true;
+	/* Let half of the packets straddle a buffer boundrary */
+	pkt_stream_replace_half(test, PKT_SIZE, test->ifobj_tx->umem->frame_size - 32);
+	test->ifobj_rx->pkt_stream->use_addr_for_fill = true;
+	testapp_validate_traffic(test);
+
+	pkt_stream_restore_default(test);
+	return true;
+}
+
+static void testapp_invalid_desc(struct test_spec *test)
+{
+	struct pkt pkts[] = {
+		/* Zero packet length at address zero allowed */
+		{0, 0, 0, true},
+		/* Zero packet length allowed */
+		{0x1000, 0, 0, true},
+		/* Straddling the start of umem */
+		{-2, PKT_SIZE, 0, false},
+		/* Packet too large */
+		{0x2000, XSK_UMEM__INVALID_FRAME_SIZE, 0, false},
+		/* After umem ends */
+		{UMEM_SIZE, PKT_SIZE, 0, false},
+		/* Straddle the end of umem */
+		{UMEM_SIZE - PKT_SIZE / 2, PKT_SIZE, 0, false},
+		/* Straddle a page boundrary */
+		{0x3000 - PKT_SIZE / 2, PKT_SIZE, 0, false},
+		/* Straddle a 2K boundrary */
+		{0x3800 - PKT_SIZE / 2, PKT_SIZE, 0, true},
+		/* Valid packet for synch so that something is received */
+		{0x4000, PKT_SIZE, 0, true}};
+
+	if (test->ifobj_tx->umem->unaligned_mode) {
+		/* Crossing a page boundrary allowed */
+		pkts[6].valid = true;
+	}
+	if (test->ifobj_tx->umem->frame_size == XSK_UMEM__DEFAULT_FRAME_SIZE / 2) {
+		/* Crossing a 2K frame size boundrary not allowed */
+		pkts[7].valid = false;
+	}
+
+	pkt_stream_generate_custom(test, pkts, ARRAY_SIZE(pkts));
+	testapp_validate_traffic(test);
+	pkt_stream_restore_default(test);
+}
+
+static void init_iface(struct ifobject *ifobj, const char *dst_mac, const char *src_mac,
+		       const char *dst_ip, const char *src_ip, const u16 dst_port,
+		       const u16 src_port, thread_func_t func_ptr)
 {
 	struct in_addr ip;
 
···
 	ifobj->dst_port = dst_port;
 	ifobj->src_port = src_port;
 
-	if (vector == tx) {
-		ifobj->fv.vector = tx;
-		ifobj->func_ptr = worker_testapp_validate_tx;
-		ifdict_tx = ifobj;
-	} else {
-		ifobj->fv.vector = rx;
-		ifobj->func_ptr = worker_testapp_validate_rx;
-		ifdict_rx = ifobj;
-	}
+	ifobj->func_ptr = func_ptr;
 }
 
-static void run_pkt_test(int mode, int type)
+static void run_pkt_test(struct test_spec *test, enum test_mode mode, enum test_type type)
 {
 	test_type = type;
 
 	/* reset defaults after potential previous test */
-	xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
-	second_step = 0;
 	stat_test_type = -1;
-	rxqsize = XSK_RING_CONS__DEFAULT_NUM_DESCS;
-	frame_headroom = XSK_UMEM__DEFAULT_FRAME_HEADROOM;
-
-	configured_mode = mode;
-
-	switch (mode) {
-	case (TEST_MODE_SKB):
-		xdp_flags |= XDP_FLAGS_SKB_MODE;
-		break;
-	case (TEST_MODE_DRV):
-		xdp_flags |= XDP_FLAGS_DRV_MODE;
-		break;
-	default:
-		break;
-	}
 
 	switch (test_type) {
 	case TEST_TYPE_STATS:
-		testapp_stats();
+		testapp_stats(test);
 		break;
 	case TEST_TYPE_TEARDOWN:
-		testapp_teardown();
+		testapp_teardown(test);
 		break;
 	case TEST_TYPE_BIDI:
-		testapp_bidi();
+		testapp_bidi(test);
 		break;
 	case TEST_TYPE_BPF_RES:
-		testapp_bpf_res();
+		testapp_bpf_res(test);
+		break;
+	case TEST_TYPE_RUN_TO_COMPLETION:
+		test_spec_set_name(test, "RUN_TO_COMPLETION");
+		testapp_validate_traffic(test);
+		break;
+	case TEST_TYPE_RUN_TO_COMPLETION_2K_FRAME:
+		test_spec_set_name(test, "RUN_TO_COMPLETION_2K_FRAME_SIZE");
+		test->ifobj_tx->umem->frame_size = 2048;
+		test->ifobj_rx->umem->frame_size = 2048;
+		pkt_stream_replace(test, DEFAULT_PKT_CNT, MIN_PKT_SIZE);
+		testapp_validate_traffic(test);
+
+		pkt_stream_restore_default(test);
+		break;
+	case TEST_TYPE_POLL:
+		test->ifobj_tx->use_poll = true;
+		test->ifobj_rx->use_poll = true;
+		test_spec_set_name(test, "POLL");
+		testapp_validate_traffic(test);
+		break;
+	case TEST_TYPE_ALIGNED_INV_DESC:
+		test_spec_set_name(test, "ALIGNED_INV_DESC");
+		testapp_invalid_desc(test);
+		break;
+	case TEST_TYPE_ALIGNED_INV_DESC_2K_FRAME:
+		test_spec_set_name(test, "ALIGNED_INV_DESC_2K_FRAME_SIZE");
+		test->ifobj_tx->umem->frame_size = 2048;
+		test->ifobj_rx->umem->frame_size = 2048;
+		testapp_invalid_desc(test);
+		break;
+	case TEST_TYPE_UNALIGNED_INV_DESC:
+		test_spec_set_name(test, "UNALIGNED_INV_DESC");
+		test->ifobj_tx->umem->unaligned_mode = true;
+		test->ifobj_rx->umem->unaligned_mode = true;
+		testapp_invalid_desc(test);
+		break;
+	case TEST_TYPE_UNALIGNED:
+		if (!testapp_unaligned(test))
+			return;
 		break;
 	default:
-		testapp_validate();
 		break;
 	}
+
+	print_ksft_result(test);
 }
 
 static struct ifobject *ifobject_create(void)
···
 	if (!ifobj)
 		return NULL;
 
-	ifobj->xsk_arr = calloc(2, sizeof(struct xsk_socket_info *));
+	ifobj->xsk_arr = calloc(MAX_SOCKETS, sizeof(*ifobj->xsk_arr));
 	if (!ifobj->xsk_arr)
 		goto out_xsk_arr;
 
-	ifobj->umem_arr = calloc(2, sizeof(struct xsk_umem_info *));
+	ifobj->umem_arr = calloc(MAX_SOCKETS, sizeof(*ifobj->umem_arr));
 	if (!ifobj->umem_arr)
 		goto out_umem_arr;
 
···
 int main(int argc, char **argv)
 {
 	struct rlimit _rlim = { RLIM_INFINITY, RLIM_INFINITY };
-	int i, j;
+	struct pkt_stream *pkt_stream_default;
+	struct ifobject *ifobj_tx, *ifobj_rx;
+	struct test_spec test;
+	u32 i, j;
 
 	if (setrlimit(RLIMIT_MEMLOCK, &_rlim))
 		exit_with_error(errno);
 
-	for (i = 0; i < MAX_INTERFACES; i++) {
-		ifdict[i] = ifobject_create();
-		if (!ifdict[i])
-			exit_with_error(ENOMEM);
-	}
+	ifobj_tx = ifobject_create();
+	if (!ifobj_tx)
+		exit_with_error(ENOMEM);
+	ifobj_rx = ifobject_create();
+	if (!ifobj_rx)
+		exit_with_error(ENOMEM);
 
 	setlocale(LC_ALL, "");
 
-	parse_command_line(argc, argv);
+	parse_command_line(ifobj_tx, ifobj_rx, argc, argv);
 
-	init_iface(ifdict[tx], MAC1, MAC2, IP1, IP2, UDP_PORT1, UDP_PORT2, tx);
-	init_iface(ifdict[rx], MAC2, MAC1, IP2, IP1, UDP_PORT2, UDP_PORT1, rx);
+	if (!validate_interface(ifobj_tx) || !validate_interface(ifobj_rx)) {
+		usage(basename(argv[0]));
+		ksft_exit_xfail();
+	}
+
+	init_iface(ifobj_tx, MAC1, MAC2, IP1, IP2, UDP_PORT1, UDP_PORT2,
+		   worker_testapp_validate_tx);
+	init_iface(ifobj_rx, MAC2, MAC1, IP2, IP1, UDP_PORT2, UDP_PORT1,
+		   worker_testapp_validate_rx);
+
+	test_spec_init(&test, ifobj_tx, ifobj_rx, 0);
+	pkt_stream_default = pkt_stream_generate(ifobj_tx->umem, DEFAULT_PKT_CNT, PKT_SIZE);
+	if (!pkt_stream_default)
+		exit_with_error(ENOMEM);
+	test.pkt_stream_default = pkt_stream_default;
 
 	ksft_set_plan(TEST_MODE_MAX * TEST_TYPE_MAX);
 
 	for (i = 0; i < TEST_MODE_MAX; i++)
 		for (j = 0; j < TEST_TYPE_MAX; j++) {
-			run_pkt_test(i, j);
+			test_spec_init(&test, ifobj_tx, ifobj_rx, i);
+			run_pkt_test(&test, i, j);
 			usleep(USLEEP_MAX);
 		}
 
-	for (i = 0; i < MAX_INTERFACES; i++)
-		ifobject_delete(ifdict[i]);
+	pkt_stream_delete(pkt_stream_default);
+	ifobject_delete(ifobj_tx);
+	ifobject_delete(ifobj_rx);
 
 	ksft_exit_pass();
 	return 0;

tools/testing/selftests/bpf/xdpxceiver.h

···
 #define MAX_INTERFACES 2
 #define MAX_INTERFACE_NAME_CHARS 7
 #define MAX_INTERFACES_NAMESPACE_CHARS 10
-#define MAX_SOCKS 1
+#define MAX_SOCKETS 2
+#define MAX_TEST_NAME_SIZE 32
 #define MAX_TEARDOWN_ITER 10
-#define MAX_BIDI_ITER 2
-#define MAX_BPF_ITER 2
 #define PKT_HDR_SIZE (sizeof(struct ethhdr) + sizeof(struct iphdr) + \
 			sizeof(struct udphdr))
 #define MIN_PKT_SIZE 64
···
 #define BATCH_SIZE 8
 #define POLL_TMOUT 1000
 #define DEFAULT_PKT_CNT (4 * 1024)
+#define DEFAULT_UMEM_BUFFERS (DEFAULT_PKT_CNT / 4)
+#define UMEM_SIZE (DEFAULT_UMEM_BUFFERS * XSK_UMEM__DEFAULT_FRAME_SIZE)
 #define RX_FULL_RXQSIZE 32
+#define DEFAULT_OFFSET 256
 #define XSK_UMEM__INVALID_FRAME_SIZE (XSK_UMEM__DEFAULT_FRAME_SIZE + 1)
 
 #define print_verbose(x...) do { if (opt_verbose) ksft_print_msg(x); } while (0)
···
 };
 
 enum test_type {
-	TEST_TYPE_NOPOLL,
+	TEST_TYPE_RUN_TO_COMPLETION,
+	TEST_TYPE_RUN_TO_COMPLETION_2K_FRAME,
 	TEST_TYPE_POLL,
+	TEST_TYPE_UNALIGNED,
+	TEST_TYPE_ALIGNED_INV_DESC,
+	TEST_TYPE_ALIGNED_INV_DESC_2K_FRAME,
+	TEST_TYPE_UNALIGNED_INV_DESC,
 	TEST_TYPE_TEARDOWN,
 	TEST_TYPE_BIDI,
 	TEST_TYPE_STATS,
···
 	STAT_TEST_TYPE_MAX
 };
 
-static int configured_mode;
 static bool opt_pkt_dump;
-static u32 num_frames = DEFAULT_PKT_CNT / 4;
-static bool second_step;
 static int test_type;
 
 static bool opt_verbose;
-
-static u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
-static u32 xdp_bind_flags = XDP_USE_NEED_WAKEUP | XDP_COPY;
 static int stat_test_type;
-static u32 rxqsize;
-static u32 frame_headroom;
 
 struct xsk_umem_info {
 	struct xsk_ring_prod fq;
 	struct xsk_ring_cons cq;
 	struct xsk_umem *umem;
+	u32 num_frames;
+	u32 frame_headroom;
 	void *buffer;
+	u32 frame_size;
+	bool unaligned_mode;
 };
 
 struct xsk_socket_info {
···
 	struct xsk_umem_info *umem;
 	struct xsk_socket *xsk;
 	u32 outstanding_tx;
-};
-
-struct flow_vector {
-	enum fvector {
-		tx,
-		rx,
-	} vector;
+	u32 rxqsize;
 };
 
 struct pkt {
 	u64 addr;
 	u32 len;
 	u32 payload;
+	bool valid;
 };
 
 struct pkt_stream {
 	u32 nb_pkts;
+	u32 rx_pkt_nb;
 	struct pkt *pkts;
+	bool use_addr_for_fill;
 };
+
+typedef void *(*thread_func_t)(void *arg);
 
 struct ifobject {
 	char ifname[MAX_INTERFACE_NAME_CHARS];
 	char nsname[MAX_INTERFACES_NAMESPACE_CHARS];
 	struct xsk_socket_info *xsk;
-	struct xsk_socket_info **xsk_arr;
-	struct xsk_umem_info **umem_arr;
+	struct xsk_socket_info *xsk_arr;
 	struct xsk_umem_info *umem;
-	void *(*func_ptr)(void *arg);
-	struct flow_vector fv;
+	struct xsk_umem_info *umem_arr;
+	thread_func_t func_ptr;
 	struct pkt_stream *pkt_stream;
 	int ns_fd;
 	u32 dst_ip;
 	u32 src_ip;
+	u32 xdp_flags;
+	u32 bind_flags;
 	u16 src_port;
 	u16 dst_port;
+	bool tx_on;
+	bool rx_on;
+	bool use_poll;
 	u8 dst_mac[ETH_ALEN];
 	u8 src_mac[ETH_ALEN];
 };
 
-static struct ifobject *ifdict[MAX_INTERFACES];
-static struct ifobject *ifdict_rx;
-static struct ifobject *ifdict_tx;
+struct test_spec {
+	struct ifobject *ifobj_tx;
+	struct ifobject *ifobj_rx;
+	struct pkt_stream *pkt_stream_default;
+	u16 total_steps;
+	u16 current_step;
+	u16 nb_sockets;
+	char name[MAX_TEST_NAME_SIZE];
+};
 
-/*threads*/
 pthread_barrier_t barr;
-pthread_t t0, t1;
 
 #endif				/* XDPXCEIVER_H */