Merge tag 'x86-apic-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 APIC updates from Thomas Gleixner:
"Rework of APIC enumeration and topology evaluation.

The current implementation has a couple of shortcomings:

- It fails to handle hybrid systems correctly.

- The APIC registration code which handles CPU number assignents is
in the middle of the APIC code and detached from the topology
evaluation.

- The various mechanisms which enumerate APICs, ACPI, MPPARSE and
guest specific ones, tweak global variables as they see fit or in
case of XENPV just hack around the generic mechanisms completely.

- The CPUID topology evaluation code is sprinkled all over the vendor
code and reevaluates global variables on every hotplug operation.

- There is no way to analyze topology on the boot CPU before bringing
up the APs. This causes problems for infrastructure like PERF which
needs to size certain aspects upfront or could be simplified if
that would be possible.

- The APIC admission and CPU number association logic is
incomprehensible and overly complex and needs to be kept around
after boot instead of completing this right after the APIC
enumeration.

This update addresses these shortcomings with the following changes:

- Rework the CPUID evaluation code so it is common for all vendors
and provides information about the APIC ID segments in a uniform
way independent of the number of segments (Thread, Core, Module,
..., Die, Package) so that this information can be computed instead
of rewriting global variables of dubious value over and over.

- A few cleanups and simplifcations of the APIC, IO/APIC and related
interfaces to prepare for the topology evaluation changes.

- Seperation of the parser stages so the early evaluation which tries
to find the APIC address can be seperately overridden from the late
evaluation which enumerates and registers the local APIC as further
preparation for sanitizing the topology evaluation.

- A new registration and admission logic which

- encapsulates the inner workings so that parsers and guest logic
cannot longer fiddle in it

- uses the APIC ID segments to build topology bitmaps at
registration time

- provides a sane admission logic

- allows to detect the crash kernel case, where CPU0 does not run
on the real BSP, automatically. This is required to prevent
sending INIT/SIPI sequences to the real BSP which would reset
the whole machine. This was so far handled by a tedious command
line parameter, which does not even work in nested crash
scenarios.

- Associates CPU number after the enumeration completed and
prevents the late registration of APICs, which was somehow
tolerated before.

- Converting all parsers and guest enumeration mechanisms over to the
new interfaces.

This allows to get rid of all global variable tweaking from the
parsers and enumeration mechanisms and sanitizes the XEN[PV]
handling so it can use CPUID evaluation for the first time.

- Mopping up existing sins by taking the information from the APIC ID
segment bitmaps.

This evaluates hybrid systems correctly on the boot CPU and allows
for cleanups and fixes in the related drivers, e.g. PERF.

The series has been extensively tested and the minimal late fallout
due to a broken ACPI/MADT table has been addressed by tightening the
admission logic further"

* tag 'x86-apic-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (76 commits)
x86/topology: Ignore non-present APIC IDs in a present package
x86/apic: Build the x86 topology enumeration functions on UP APIC builds too
smp: Provide 'setup_max_cpus' definition on UP too
smp: Avoid 'setup_max_cpus' namespace collision/shadowing
x86/bugs: Use fixed addressing for VERW operand
x86/cpu/topology: Get rid of cpuinfo::x86_max_cores
x86/cpu/topology: Provide __num_[cores|threads]_per_package
x86/cpu/topology: Rename topology_max_die_per_package()
x86/cpu/topology: Rename smp_num_siblings
x86/cpu/topology: Retrieve cores per package from topology bitmaps
x86/cpu/topology: Use topology logical mapping mechanism
x86/cpu/topology: Provide logical pkg/die mapping
x86/cpu/topology: Simplify cpu_mark_primary_thread()
x86/cpu/topology: Mop up primary thread mask handling
x86/cpu/topology: Use topology bitmaps for sizing
x86/cpu/topology: Let XEN/PV use topology from CPUID/MADT
x86/xen/smp_pv: Count number of vCPUs early
x86/cpu/topology: Assign hotpluggable CPUIDs during init
x86/cpu/topology: Reject unknown APIC IDs on ACPI hotplug
x86/topology: Add a mechanism to track topology via APIC IDs
...

Documentation/admin-guide/kdump/kdump.rst

···
    CPU is enough for kdump kernel to dump vmcore on most of systems.
 
    However, you can also specify nr_cpus=X to enable multiple processors
-   in kdump kernel. In this case, "disable_cpu_apicid=" is needed to
-   tell kdump kernel which cpu is 1st kernel's BSP. Please refer to
-   admin-guide/kernel-parameters.txt for more details.
+   in kdump kernel.
 
    With CONFIG_SMP=n, the above things are not related.
 
···
   to use multi-thread programs with it, such as parallel dump feature of
   makedumpfile. Otherwise, the multi-thread program may have a great
   performance degradation. To enable multi-cpu support, you should bring up an
-  SMP dump-capture kernel and specify maxcpus/nr_cpus, disable_cpu_apicid=[X]
-  options while loading it.
+  SMP dump-capture kernel and specify maxcpus/nr_cpus options while loading it.
 
 * For s390x there are two kdump modes: If a ELF header is specified with
   the elfcorehdr= kernel parameter, it is used by the kdump kernel as it

Documentation/admin-guide/kernel-parameters.txt

···
 			Disable TLBIE instruction. Currently does not work
 			with KVM, with HASH MMU, or with coherent accelerators.
 
-	disable_cpu_apicid= [X86,APIC,SMP]
-			Format: <int>
-			The number of initial APIC ID for the
-			corresponding CPU to be disabled at boot,
-			mostly used for the kdump 2nd kernel to
-			disable BSP to wake up multiple CPUs without
-			causing system reset or hang due to sending
-			INIT from AP to BSP.
-
 	disable_ddw	[PPC/PSERIES,EARLY]
 			Disable Dynamic DMA Window support. Use this
 			to workaround buggy firmware.

Documentation/arch/x86/topology.rst

···
 
 Package-related topology information in the kernel:
 
-  - cpuinfo_x86.x86_max_cores:
+  - topology_num_threads_per_package()
 
-    The number of cores in a package. This information is retrieved via CPUID.
+    The number of threads in a package.
 
-  - cpuinfo_x86.x86_max_dies:
+  - topology_num_cores_per_package()
 
-    The number of dies in a package. This information is retrieved via CPUID.
+    The number of cores in a package.
+
+  - topology_max_dies_per_package()
+
+    The maximum number of dies in a package.
 
   - cpuinfo_x86.topo.die_id:
 
-    The physical ID of the die. This information is retrieved via CPUID.
+    The physical ID of the die.
 
   - cpuinfo_x86.topo.pkg_id:
 
···
 
 AMDs nomenclature for a CMT core is "Compute Unit". The kernel always uses
 "core".
-
-Core-related topology information in the kernel:
-
-  - smp_num_siblings:
-
-    The number of threads in a core. The number of threads in a package can be
-    calculated by::
-
-	threads_per_package = cpuinfo_x86.x86_max_cores * smp_num_siblings
-
 
 Threads
 =======

arch/x86/events/amd/core.c

···
 	if (!x86_pmu.amd_nb_constraints)
 		return;
 
-	nb_id = topology_die_id(cpu);
+	nb_id = topology_amd_node_id(cpu);
 	WARN_ON_ONCE(nb_id == BAD_APICID);
 
 	for_each_online_cpu(i) {

arch/x86/events/intel/cstate.c

···
 	}
 
 	if (has_cstate_pkg) {
-		if (topology_max_die_per_package() > 1) {
+		if (topology_max_dies_per_package() > 1) {
 			err = perf_pmu_register(&cstate_pkg_pmu,
 						"cstate_die", -1);
 		} else {

arch/x86/events/intel/uncore.c

···
 		return -ENODEV;
 
 	__uncore_max_dies =
-		topology_max_packages() * topology_max_die_per_package();
+		topology_max_packages() * topology_max_dies_per_package();
 
 	id = x86_match_cpu(intel_uncore_match);
 	if (!id) {

arch/x86/events/intel/uncore_nhmex.c

···
 		uncore_nhmex = true;
 	else
 		nhmex_uncore_mbox.event_descs = wsmex_uncore_mbox_events;
-	if (nhmex_uncore_cbox.num_boxes > boot_cpu_data.x86_max_cores)
-		nhmex_uncore_cbox.num_boxes = boot_cpu_data.x86_max_cores;
+	if (nhmex_uncore_cbox.num_boxes > topology_num_cores_per_package())
+		nhmex_uncore_cbox.num_boxes = topology_num_cores_per_package();
 	uncore_msr_uncores = nhmex_msr_uncores;
 }
 /* end of Nehalem-EX uncore support */

arch/x86/events/intel/uncore_snb.c

···
 void snb_uncore_cpu_init(void)
 {
 	uncore_msr_uncores = snb_msr_uncores;
-	if (snb_uncore_cbox.num_boxes > boot_cpu_data.x86_max_cores)
-		snb_uncore_cbox.num_boxes = boot_cpu_data.x86_max_cores;
+	if (snb_uncore_cbox.num_boxes > topology_num_cores_per_package())
+		snb_uncore_cbox.num_boxes = topology_num_cores_per_package();
 }
 
 static void skl_uncore_msr_init_box(struct intel_uncore_box *box)
···
 void skl_uncore_cpu_init(void)
 {
 	uncore_msr_uncores = skl_msr_uncores;
-	if (skl_uncore_cbox.num_boxes > boot_cpu_data.x86_max_cores)
-		skl_uncore_cbox.num_boxes = boot_cpu_data.x86_max_cores;
+	if (skl_uncore_cbox.num_boxes > topology_num_cores_per_package())
+		skl_uncore_cbox.num_boxes = topology_num_cores_per_package();
 	snb_uncore_arb.ops = &skl_uncore_msr_ops;
 }
 

arch/x86/events/intel/uncore_snbep.c

···
 
 void snbep_uncore_cpu_init(void)
 {
-	if (snbep_uncore_cbox.num_boxes > boot_cpu_data.x86_max_cores)
-		snbep_uncore_cbox.num_boxes = boot_cpu_data.x86_max_cores;
+	if (snbep_uncore_cbox.num_boxes > topology_num_cores_per_package())
+		snbep_uncore_cbox.num_boxes = topology_num_cores_per_package();
 	uncore_msr_uncores = snbep_msr_uncores;
 }
 
···
 	 */
 	for (i = 0; i < 8; i++) {
 		if (nodeid == GIDNIDMAP(gidnid, i)) {
-			if (topology_max_die_per_package() > 1)
+			if (topology_max_dies_per_package() > 1)
 				die_id = i;
 			else
 				die_id = topology_phys_to_logical_pkg(i);
···
 
 void ivbep_uncore_cpu_init(void)
 {
-	if (ivbep_uncore_cbox.num_boxes > boot_cpu_data.x86_max_cores)
-		ivbep_uncore_cbox.num_boxes = boot_cpu_data.x86_max_cores;
+	if (ivbep_uncore_cbox.num_boxes > topology_num_cores_per_package())
+		ivbep_uncore_cbox.num_boxes = topology_num_cores_per_package();
 	uncore_msr_uncores = ivbep_msr_uncores;
 }
 
···
 
 void hswep_uncore_cpu_init(void)
 {
-	if (hswep_uncore_cbox.num_boxes > boot_cpu_data.x86_max_cores)
-		hswep_uncore_cbox.num_boxes = boot_cpu_data.x86_max_cores;
+	if (hswep_uncore_cbox.num_boxes > topology_num_cores_per_package())
+		hswep_uncore_cbox.num_boxes = topology_num_cores_per_package();
 
 	/* Detect 6-8 core systems with only two SBOXes */
 	if (hswep_has_limit_sbox(HSWEP_PCU_DID))
···
 
 void bdx_uncore_cpu_init(void)
 {
-	if (bdx_uncore_cbox.num_boxes > boot_cpu_data.x86_max_cores)
-		bdx_uncore_cbox.num_boxes = boot_cpu_data.x86_max_cores;
+	if (bdx_uncore_cbox.num_boxes > topology_num_cores_per_package())
+		bdx_uncore_cbox.num_boxes = topology_num_cores_per_package();
 	uncore_msr_uncores = bdx_msr_uncores;
 
 	/* Detect systems with no SBOXes */

arch/x86/events/rapl.c

···
 
 static int __init init_rapl_pmus(void)
 {
-	int maxdie = topology_max_packages() * topology_max_die_per_package();
+	int maxdie = topology_max_packages() * topology_max_dies_per_package();
 	size_t size;
 
 	size = sizeof(*rapl_pmus) + maxdie * sizeof(struct rapl_pmu *);

arch/x86/hyperv/hv_vtl.c

···
 	x86_init.timers.timer_init = x86_init_noop;
 
 	/* Avoid searching for BIOS MP tables */
-	x86_init.mpparse.find_smp_config = x86_init_noop;
-	x86_init.mpparse.get_smp_config = x86_init_uint_noop;
+	x86_init.mpparse.find_mptable = x86_init_noop;
+	x86_init.mpparse.early_parse_smp_cfg = x86_init_noop;
+	x86_init.mpparse.parse_smp_cfg = x86_init_noop;
 
 	x86_platform.get_wallclock = get_rtc_noop;
 	x86_platform.set_wallclock = set_rtc_noop;

arch/x86/include/asm/apic.h

···
 static inline void x86_32_probe_apic(void) { }
 #endif
 
+extern u32 cpuid_to_apicid[];
+
+#define CPU_ACPIID_INVALID	U32_MAX
+
 #ifdef CONFIG_X86_LOCAL_APIC
 
 extern int apic_verbosity;
···
 
 extern bool apic_is_disabled;
 extern unsigned int lapic_timer_period;
-
-extern u32 cpuid_to_apicid[];
 
 extern enum apic_intr_mode_id apic_intr_mode;
 enum apic_intr_mode_id {
···
 
 extern void apic_send_IPI_allbutself(unsigned int vector);
 
+extern void topology_register_apic(u32 apic_id, u32 acpi_id, bool present);
+extern void topology_register_boot_apic(u32 apic_id);
+extern int topology_hotplug_apic(u32 apic_id, u32 acpi_id);
+extern void topology_hotunplug_apic(unsigned int cpu);
+extern void topology_apply_cmdline_limits_early(void);
+extern void topology_init_possible_cpus(void);
+extern void topology_reset_possible_cpus_up(void);
+
 #else /* !CONFIG_X86_LOCAL_APIC */
 static inline void lapic_shutdown(void) { }
 #define local_apic_timer_c2_ok		1
···
 static inline void lapic_assign_system_vectors(void) { }
 static inline void lapic_assign_legacy_vector(unsigned int i, bool r) { }
 static inline bool apic_needs_pit(void) { return true; }
+static inline void topology_apply_cmdline_limits_early(void) { }
+static inline void topology_init_possible_cpus(void) { }
 #endif /* !CONFIG_X86_LOCAL_APIC */
 
 #ifdef CONFIG_X86_X2APIC
···
 	/* Probe, setup and smpboot functions */
 	int	(*probe)(void);
 	int	(*acpi_madt_oem_check)(char *oem_id, char *oem_table_id);
-	bool	(*apic_id_registered)(void);
 
-	bool	(*check_apicid_used)(physid_mask_t *map, u32 apicid);
 	void	(*init_apic_ldr)(void);
-	void	(*ioapic_phys_id_map)(physid_mask_t *phys_map, physid_mask_t *retmap);
 	u32	(*cpu_present_to_apicid)(int mps_cpu);
-	u32	(*phys_pkg_id)(u32 cpuid_apic, int index_msb);
 
 	u32	(*get_apic_id)(u32 id);
-	u32	(*set_apic_id)(u32 apicid);
 
 	/* wakeup_secondary_cpu */
 	int	(*wakeup_secondary_cpu)(u32 apicid, unsigned long start_eip);
···
 extern u32 apic_default_calc_apicid(unsigned int cpu);
 extern u32 apic_flat_calc_apicid(unsigned int cpu);
 
-extern void default_ioapic_phys_id_map(physid_mask_t *phys_map, physid_mask_t *retmap);
 extern u32 default_cpu_present_to_apicid(int mps_cpu);
 
 void apic_send_nmi_to_offline_cpu(unsigned int cpu);

arch/x86/include/asm/cpu.h

···
 #include <linux/percpu.h>
 #include <asm/ibt.h>
 
-#ifdef CONFIG_SMP
-
-extern void prefill_possible_map(void);
-
-#else /* CONFIG_SMP */
-
-static inline void prefill_possible_map(void) {}
-
+#ifndef CONFIG_SMP
 #define cpu_physical_id(cpu)			boot_cpu_physical_apicid
 #define cpu_acpi_id(cpu)			0
 #define safe_smp_processor_id()			0
-
 #endif /* CONFIG_SMP */
 
 #ifdef CONFIG_HOTPLUG_CPU

arch/x86/include/asm/cpuid.h

···
 	return edx;
 }
 
+static inline void __cpuid_read(unsigned int leaf, unsigned int subleaf, u32 *regs)
+{
+	regs[CPUID_EAX] = leaf;
+	regs[CPUID_ECX] = subleaf;
+	__cpuid(regs + CPUID_EAX, regs + CPUID_EBX, regs + CPUID_ECX, regs + CPUID_EDX);
+}
+
+#define cpuid_subleaf(leaf, subleaf, regs) {		\
+	static_assert(sizeof(*(regs)) == 16);		\
+	__cpuid_read(leaf, subleaf, (u32 *)(regs));	\
+}
+
+#define cpuid_leaf(leaf, regs) {			\
+	static_assert(sizeof(*(regs)) == 16);		\
+	__cpuid_read(leaf, 0, (u32 *)(regs));		\
+}
+
+static inline void __cpuid_read_reg(unsigned int leaf, unsigned int subleaf,
+				    enum cpuid_regs_idx regidx, u32 *reg)
+{
+	u32 regs[4];
+
+	__cpuid_read(leaf, subleaf, regs);
+	*reg = regs[regidx];
+}
+
+#define cpuid_subleaf_reg(leaf, subleaf, regidx, reg) {		\
+	static_assert(sizeof(*(reg)) == 4);			\
+	__cpuid_read_reg(leaf, subleaf, regidx, (u32 *)(reg));	\
+}
+
+#define cpuid_leaf_reg(leaf, regidx, reg) {			\
+	static_assert(sizeof(*(reg)) == 4);			\
+	__cpuid_read_reg(leaf, 0, regidx, (u32 *)(reg));	\
+}
+
 static __always_inline bool cpuid_function_is_indexed(u32 function)
 {
 	switch (function) {

arch/x86/include/asm/io_apic.h

···
 extern int restore_ioapic_entries(void);
 
 extern void setup_ioapic_ids_from_mpc(void);
-extern void setup_ioapic_ids_from_mpc_nocheck(void);
 
 extern int mp_find_ioapic(u32 gsi);
 extern int mp_find_ioapic_pin(int ioapic, u32 gsi);

arch/x86/include/asm/mpspec.h

···
 #ifndef _ASM_X86_MPSPEC_H
 #define _ASM_X86_MPSPEC_H
 
+#include <linux/types.h>
 
 #include <asm/mpspec_def.h>
 #include <asm/x86_init.h>
···
 # define smp_found_config 0
 #endif
 
-static inline void get_smp_config(void)
-{
-	x86_init.mpparse.get_smp_config(0);
-}
-
-static inline void early_get_smp_config(void)
-{
-	x86_init.mpparse.get_smp_config(1);
-}
-
-static inline void find_smp_config(void)
-{
-	x86_init.mpparse.find_smp_config();
-}
-
 #ifdef CONFIG_X86_MPPARSE
 extern void e820__memblock_alloc_reserved_mpc_new(void);
 extern int enable_update_mptable;
-extern void default_find_smp_config(void);
-extern void default_get_smp_config(unsigned int early);
+extern void mpparse_find_mptable(void);
+extern void mpparse_parse_early_smp_config(void);
+extern void mpparse_parse_smp_config(void);
 #else
 static inline void e820__memblock_alloc_reserved_mpc_new(void) { }
-#define enable_update_mptable 0
-#define default_find_smp_config x86_init_noop
-#define default_get_smp_config x86_init_uint_noop
+#define enable_update_mptable		0
+#define mpparse_find_mptable		x86_init_noop
+#define mpparse_parse_early_smp_config	x86_init_noop
+#define mpparse_parse_smp_config	x86_init_noop
 #endif
 
-int generic_processor_info(int apicid);
+extern DECLARE_BITMAP(phys_cpu_present_map, MAX_LOCAL_APIC);
 
-#define PHYSID_ARRAY_SIZE	BITS_TO_LONGS(MAX_LOCAL_APIC)
-
-struct physid_mask {
-	unsigned long mask[PHYSID_ARRAY_SIZE];
-};
-
-typedef struct physid_mask physid_mask_t;
-
-#define physid_set(physid, map)			set_bit(physid, (map).mask)
-#define physid_isset(physid, map)		test_bit(physid, (map).mask)
-
-#define physids_or(dst, src1, src2)					\
-	bitmap_or((dst).mask, (src1).mask, (src2).mask, MAX_LOCAL_APIC)
-
-#define physids_clear(map)					\
-	bitmap_zero((map).mask, MAX_LOCAL_APIC)
-
-#define physids_empty(map)					\
-	bitmap_empty((map).mask, MAX_LOCAL_APIC)
-
-static inline void physids_promote(unsigned long physids, physid_mask_t *map)
+static inline void reset_phys_cpu_present_map(u32 apicid)
 {
-	physids_clear(*map);
-	map->mask[0] = physids;
+	bitmap_zero(phys_cpu_present_map, MAX_LOCAL_APIC);
+	set_bit(apicid, phys_cpu_present_map);
 }
 
-static inline void physid_set_mask_of_physid(int physid, physid_mask_t *map)
+static inline void copy_phys_cpu_present_map(unsigned long *dst)
 {
-	physids_clear(*map);
-	physid_set(physid, *map);
+	bitmap_copy(dst, phys_cpu_present_map, MAX_LOCAL_APIC);
 }
-
-#define PHYSID_MASK_ALL		{ {[0 ... PHYSID_ARRAY_SIZE-1] = ~0UL} }
-#define PHYSID_MASK_NONE	{ {[0 ... PHYSID_ARRAY_SIZE-1] = 0UL} }
-
-extern physid_mask_t phys_cpu_present_map;
 
 #endif /* _ASM_X86_MPSPEC_H */

arch/x86/include/asm/nospec-branch.h

···
  * Note: Only the memory operand variant of VERW clears the CPU buffers.
  */
 .macro CLEAR_CPU_BUFFERS
-	ALTERNATIVE "", __stringify(verw _ASM_RIP(mds_verw_sel)), X86_FEATURE_CLEAR_CPU_BUF
+	ALTERNATIVE "", __stringify(verw mds_verw_sel), X86_FEATURE_CLEAR_CPU_BUF
 .endm
 
 #else /* __ASSEMBLY__ */

arch/x86/include/asm/perf_event_p4.h

···
 static inline int p4_ht_active(void)
 {
 #ifdef CONFIG_SMP
-	return smp_num_siblings > 1;
+	return __max_threads_per_core > 1;
 #endif
 	return 0;
 }
···
 static inline int p4_ht_thread(int cpu)
 {
 #ifdef CONFIG_SMP
-	if (smp_num_siblings == 2)
+	if (__max_threads_per_core == 2)
 		return cpu != cpumask_first(this_cpu_cpumask_var_ptr(cpu_sibling_map));
 #endif
 	return 0;

arch/x86/include/asm/processor.h

···
 	u32			logical_pkg_id;
 	u32			logical_die_id;
 
+	// AMD Node ID and Nodes per Package info
+	u32			amd_node_id;
+
 	// Cache level topology IDs
 	u32			llc_id;
 	u32			l2c_id;
···
 #endif
 	__u8			x86_virt_bits;
 	__u8			x86_phys_bits;
-	/* CPUID returned core id bits: */
-	__u8			x86_coreid_bits;
 	/* Max extended CPUID function supported: */
 	__u32			extended_cpuid_level;
 	/* Maximum supported CPUID level, -1=no CPUID: */
···
 	unsigned long		loops_per_jiffy;
 	/* protected processor identification number */
 	u64			ppin;
-	/* cpuid returned max cores value: */
-	u16			x86_max_cores;
 	u16			x86_clflush_size;
 	/* number of cores as seen by the OS: */
 	u16			booted_cores;
···
 }
 
 #ifdef CONFIG_CPU_SUP_AMD
-extern u32 amd_get_nodes_per_socket(void);
 extern u32 amd_get_highest_perf(void);
 extern void amd_clear_divider(void);
 extern void amd_check_microcode(void);
 #else
-static inline u32 amd_get_nodes_per_socket(void)	{ return 0; }
 static inline u32 amd_get_highest_perf(void)		{ return 0; }
 static inline void amd_clear_divider(void)		{ }
 static inline void amd_check_microcode(void)		{ }

arch/x86/include/asm/prom.h

···
 extern u64 initial_dtb;
 extern void add_dtb(u64 data);
 void x86_of_pci_init(void);
-void x86_dtb_init(void);
+void x86_dtb_parse_smp_config(void);
 #else
 static inline void add_dtb(u64 data) { }
 static inline void x86_of_pci_init(void) { }
-static inline void x86_dtb_init(void) { }
+static inline void x86_dtb_parse_smp_config(void) { }
 #define of_ioapic 0
 #endif
 

arch/x86/include/asm/smp.h

···
 #include <asm/current.h>
 #include <asm/thread_info.h>
 
-extern int smp_num_siblings;
-extern unsigned int num_processors;
-
 DECLARE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_sibling_map);
 DECLARE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_core_map);
 DECLARE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_die_map);
···
 void native_smp_prepare_boot_cpu(void);
 void smp_prepare_cpus_common(void);
 void native_smp_prepare_cpus(unsigned int max_cpus);
-void calculate_max_logical_packages(void);
 void native_smp_cpus_done(unsigned int max_cpus);
 int common_cpu_up(unsigned int cpunum, struct task_struct *tidle);
 int native_kick_ap(unsigned int cpu, struct task_struct *tidle);
···
 	return (struct cpumask *)cpumask_of(0);
 }
 #endif /* CONFIG_SMP */
-
-extern unsigned disabled_cpus;
 
 #ifdef CONFIG_DEBUG_NMI_SELFTEST
 extern void nmi_selftest(void);

arch/x86/include/asm/topology.h

···
 
 #include <asm-generic/topology.h>
 
+/* Topology information */
+enum x86_topology_domains {
+	TOPO_SMT_DOMAIN,
+	TOPO_CORE_DOMAIN,
+	TOPO_MODULE_DOMAIN,
+	TOPO_TILE_DOMAIN,
+	TOPO_DIE_DOMAIN,
+	TOPO_DIEGRP_DOMAIN,
+	TOPO_PKG_DOMAIN,
+	TOPO_MAX_DOMAIN,
+};
+
+struct x86_topology_system {
+	unsigned int	dom_shifts[TOPO_MAX_DOMAIN];
+	unsigned int	dom_size[TOPO_MAX_DOMAIN];
+};
+
+extern struct x86_topology_system x86_topo_system;
+
+static inline unsigned int topology_get_domain_size(enum x86_topology_domains dom)
+{
+	return x86_topo_system.dom_size[dom];
+}
+
+static inline unsigned int topology_get_domain_shift(enum x86_topology_domains dom)
+{
+	return dom == TOPO_SMT_DOMAIN ? 0 : x86_topo_system.dom_shifts[dom - 1];
+}
+
 extern const struct cpumask *cpu_coregroup_mask(int cpu);
 extern const struct cpumask *cpu_clustergroup_mask(int cpu);
 
···
 #define topology_core_id(cpu)			(cpu_data(cpu).topo.core_id)
 #define topology_ppin(cpu)			(cpu_data(cpu).ppin)
 
-extern unsigned int __max_die_per_package;
+#define topology_amd_node_id(cpu)		(cpu_data(cpu).topo.amd_node_id)
+
+extern unsigned int __max_dies_per_package;
+extern unsigned int __max_logical_packages;
+extern unsigned int __max_threads_per_core;
+extern unsigned int __num_threads_per_package;
+extern unsigned int __num_cores_per_package;
+
+static inline unsigned int topology_max_packages(void)
+{
+	return __max_logical_packages;
+}
+
+static inline unsigned int topology_max_dies_per_package(void)
+{
+	return __max_dies_per_package;
+}
+
+static inline unsigned int topology_num_cores_per_package(void)
+{
+	return __num_cores_per_package;
+}
+
+static inline unsigned int topology_num_threads_per_package(void)
+{
+	return __num_threads_per_package;
+}
+
+#ifdef CONFIG_X86_LOCAL_APIC
+int topology_get_logical_id(u32 apicid, enum x86_topology_domains at_level);
+#else
+static inline int topology_get_logical_id(u32 apicid, enum x86_topology_domains at_level)
+{
+	return 0;
+}
+#endif
 
 #ifdef CONFIG_SMP
 #define topology_cluster_id(cpu)		(cpu_data(cpu).topo.l2c_id)
···
 #define topology_core_cpumask(cpu)		(per_cpu(cpu_core_map, cpu))
 #define topology_sibling_cpumask(cpu)		(per_cpu(cpu_sibling_map, cpu))
 
-extern unsigned int __max_logical_packages;
-#define topology_max_packages()			(__max_logical_packages)
 
-static inline int topology_max_die_per_package(void)
+static inline int topology_phys_to_logical_pkg(unsigned int pkg)
 {
-	return __max_die_per_package;
+	return topology_get_logical_id(pkg << x86_topo_system.dom_shifts[TOPO_PKG_DOMAIN],
+				       TOPO_PKG_DOMAIN);
 }
 
 extern int __max_smt_threads;
···
 
 #include <linux/cpu_smt.h>
 
-int topology_update_package_map(unsigned int apicid, unsigned int cpu);
-int topology_update_die_map(unsigned int dieid, unsigned int cpu);
-int topology_phys_to_logical_pkg(unsigned int pkg);
+extern unsigned int __amd_nodes_per_pkg;
+
+static inline unsigned int topology_amd_nodes_per_pkg(void)
+{
+	return __amd_nodes_per_pkg;
+}
 
 extern struct cpumask __cpu_primary_thread_mask;
 #define cpu_primary_thread_mask ((const struct cpumask *)&__cpu_primary_thread_mask)
···
 {
 	return cpumask_test_cpu(cpu, cpu_primary_thread_mask);
 }
+
 #else /* CONFIG_SMP */
-#define topology_max_packages()			(1)
-static inline int
-topology_update_package_map(unsigned int apicid, unsigned int cpu) { return 0; }
-static inline int
-topology_update_die_map(unsigned int dieid, unsigned int cpu) { return 0; }
 static inline int topology_phys_to_logical_pkg(unsigned int pkg) { return 0; }
-static inline int topology_max_die_per_package(void) { return 1; }
 static inline int topology_max_smt_threads(void) { return 1; }
 static inline bool topology_is_primary_thread(unsigned int cpu) { return true; }
+static inline unsigned int topology_amd_nodes_per_pkg(void) { return 0; };
 #endif /* !CONFIG_SMP */
 
 static inline void arch_fix_phys_package_id(int num, u32 slot)

arch/x86/include/asm/x86_init.h

···
 /**
  * struct x86_init_mpparse - platform specific mpparse ops
  * @setup_ioapic_ids:		platform specific ioapic id override
- * @find_smp_config:		find the smp configuration
- * @get_smp_config:		get the smp configuration
+ * @find_mptable:		Find MPTABLE early to reserve the memory region
+ * @early_parse_smp_cfg:	Parse the SMP configuration data early before initmem_init()
+ * @parse_smp_cfg:		Parse the SMP configuration data
  */
 struct x86_init_mpparse {
 	void (*setup_ioapic_ids)(void);
-	void (*find_smp_config)(void);
-	void (*get_smp_config)(unsigned int early);
+	void (*find_mptable)(void);
+	void (*early_parse_smp_cfg)(void);
+	void (*parse_smp_cfg)(void);
 };
 
 /**

arch/x86/kernel/acpi/boot.c

···
 	return 0;
 }
 
-/**
- * acpi_register_lapic - register a local apic and generates a logic cpu number
- * @id: local apic id to register
- * @acpiid: ACPI id to register
- * @enabled: this cpu is enabled or not
- *
- * Returns the logic cpu number which maps to the local apic
- */
-static int acpi_register_lapic(int id, u32 acpiid, u8 enabled)
-{
-	int cpu;
-
-	if (id >= MAX_LOCAL_APIC) {
-		pr_info("skipped apicid that is too big\n");
-		return -EINVAL;
-	}
-
-	if (!enabled) {
-		++disabled_cpus;
-		return -EINVAL;
-	}
-
-	cpu = generic_processor_info(id);
-	if (cpu >= 0)
-		early_per_cpu(x86_cpu_to_acpiid, cpu) = acpiid;
-
-	return cpu;
-}
-
 static bool __init acpi_is_processor_usable(u32 lapic_flags)
 {
 	if (lapic_flags & ACPI_MADT_ENABLED)
···
 		return 0;
 	}
 
-	acpi_register_lapic(apic_id, processor->uid, enabled);
+	topology_register_apic(apic_id, processor->uid, enabled);
 #else
 	pr_warn("x2apic entry ignored\n");
 #endif
···
 	 * to not preallocating memory for all NR_CPUS
 	 * when we use CPU hotplug.
 	 */
-	acpi_register_lapic(processor->id,	/* APIC ID */
-			    processor->processor_id, /* ACPI ID */
-			    processor->lapic_flags & ACPI_MADT_ENABLED);
+	topology_register_apic(processor->id,	/* APIC ID */
+			       processor->processor_id, /* ACPI ID */
+			       processor->lapic_flags & ACPI_MADT_ENABLED);
 
 	has_lapic_cpus = true;
 	return 0;
···
 
 	acpi_table_print_madt_entry(&header->common);
 
-	acpi_register_lapic((processor->id << 8) | processor->eid,/* APIC ID */
-			    processor->processor_id, /* ACPI ID */
-			    processor->lapic_flags & ACPI_MADT_ENABLED);
+	topology_register_apic((processor->id << 8) | processor->eid,/* APIC ID */
+			       processor->processor_id, /* ACPI ID */
+			       processor->lapic_flags & ACPI_MADT_ENABLED);
 
 	return 0;
 }
···
 	return 0;
 }
 
-int acpi_map_cpu(acpi_handle handle, phys_cpuid_t physid, u32 acpi_id,
-		 int *pcpu)
+int acpi_map_cpu(acpi_handle handle, phys_cpuid_t physid, u32 acpi_id, int *pcpu)
 {
-	int cpu;
+	int cpu = topology_hotplug_apic(physid, acpi_id);
 
-	cpu = acpi_register_lapic(physid, acpi_id, ACPI_MADT_ENABLED);
 	if (cpu < 0) {
 		pr_info("Unable to map lapic to logical cpu number\n");
 		return cpu;
···
 #ifdef CONFIG_ACPI_NUMA
 	set_apicid_to_node(per_cpu(x86_cpu_to_apicid, cpu), NUMA_NO_NODE);
 #endif
-
-	per_cpu(x86_cpu_to_apicid, cpu) = BAD_APICID;
-	set_cpu_present(cpu, false);
-	num_processors--;
-
-	return (0);
+	topology_hotunplug_apic(cpu);
+	return 0;
 }
 EXPORT_SYMBOL(acpi_unmap_cpu);
-#endif				/* CONFIG_ACPI_HOTPLUG_CPU */
+#endif	/* CONFIG_ACPI_HOTPLUG_CPU */
 
 int acpi_register_ioapic(acpi_handle handle, u64 phys_addr, u32 gsi_base)
 {

arch/x86/kernel/amd_nb.c

···
 
 int amd_get_subcaches(int cpu)
 {
-	struct pci_dev *link = node_to_amd_nb(topology_die_id(cpu))->link;
+	struct pci_dev *link = node_to_amd_nb(topology_amd_node_id(cpu))->link;
 	unsigned int mask;
 
 	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
···
 int amd_set_subcaches(int cpu, unsigned long mask)
 {
 	static unsigned int reset, ban;
-	struct amd_northbridge *nb = node_to_amd_nb(topology_die_id(cpu));
+	struct amd_northbridge *nb = node_to_amd_nb(topology_amd_node_id(cpu));
 	unsigned int reg;
 	int cuid;
 

arch/x86/kernel/apic/apic.c

···
 #include <linux/kernel_stat.h>
 #include <linux/mc146818rtc.h>
 #include <linux/acpi_pmtmr.h>
+#include <linux/bitmap.h>
 #include <linux/clockchips.h>
 #include <linux/interrupt.h>
 #include <linux/memblock.h>
···
 
 #include "local.h"
 
-unsigned int num_processors;
-
-unsigned disabled_cpus;
-
 /* Processor that is doing the boot up */
 u32 boot_cpu_physical_apicid __ro_after_init = BAD_APICID;
 EXPORT_SYMBOL_GPL(boot_cpu_physical_apicid);
 
 u8 boot_cpu_apic_version __ro_after_init;
-
-/*
- * Bitmask of physically existing CPUs:
- */
-physid_mask_t phys_cpu_present_map;
-
-/*
- * Processor to be disabled specified by kernel parameter
- * disable_cpu_apicid=<int>, mostly used for the kdump 2nd kernel to
- * avoid undefined behaviour caused by sending INIT from AP to BSP.
- */
-static u32 disabled_cpu_apicid __ro_after_init = BAD_APICID;
 
 /*
  * This variable controls which CPUs receive external NMIs.  By default,
···
 {
 	return x2apic_mode || apic_mmio_base;
 }
-
-/*
- * Map cpu index to physical APIC ID
- */
-DEFINE_EARLY_PER_CPU_READ_MOSTLY(u32, x86_cpu_to_apicid, BAD_APICID);
-DEFINE_EARLY_PER_CPU_READ_MOSTLY(u32, x86_cpu_to_acpiid, U32_MAX);
-EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_apicid);
-EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_acpiid);
 
 #ifdef CONFIG_X86_32
 /* Local APIC was disabled by the BIOS and enabled by the kernel */
···
 
 	return icr1 | ((u64)icr2 << 32);
 }
-
-#ifdef CONFIG_X86_32
-/**
- * get_physical_broadcast - Get number of physical broadcast IDs
- */
-int get_physical_broadcast(void)
-{
-	return modern_apic() ? 0xff : 0xf;
-}
-#endif
 
 /**
  * lapic_get_maxlvt - get the maximum number of local vector table entries
···
 		apic_write(APIC_ESR, 0);
 	}
 #endif
-	/* Validate that the APIC is registered if required */
-	BUG_ON(apic->apic_id_registered && !apic->apic_id_registered());
-
 	/*
 	 * Intel recommends to set DFR, LDR and TPR before enabling
 	 * an APIC.  See e.g. "AP-388 82489DX User's Manual" (Intel
···
 	end_local_APIC_setup();
 }
 
-static __init void cpu_set_boot_apic(void);
-
 static __init void apic_read_boot_cpu_id(bool x2apic)
 {
 	/*
···
 		boot_cpu_physical_apicid = read_apic_id();
 		boot_cpu_apic_version = GET_APIC_VERSION(apic_read(APIC_LVR));
 	}
-	cpu_set_boot_apic();
+	topology_register_boot_apic(boot_cpu_physical_apicid);
+	x86_32_probe_bigsmp_early();
 }
 
 #ifdef CONFIG_X86_X2APIC
···
 			pr_info("APIC: disable apic facility\n");
 			apic_disable();
 		}
-		num_processors = 1;
 	}
 }
 
···
 	apic_write(APIC_LVT1, value);
 }
 
-/*
- * The number of allocated logical CPU IDs. Since logical CPU IDs are allocated
- * contiguously, it equals to current allocated max logical CPU ID plus 1.
- * All allocated CPU IDs should be in the [0, nr_logical_cpuids) range,
- * so the maximum of nr_logical_cpuids is nr_cpu_ids.
- *
- * NOTE: Reserve 0 for BSP.
- */
-static int nr_logical_cpuids = 1;
-
-/*
- * Used to store mapping between logical CPU IDs and APIC IDs.
- */
-u32 cpuid_to_apicid[] = { [0 ... NR_CPUS - 1] = BAD_APICID, };
-
-bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
-{
-	return phys_id == (u64)cpuid_to_apicid[cpu];
-}
-
-#ifdef CONFIG_SMP
-static void cpu_mark_primary_thread(unsigned int cpu, unsigned int apicid)
-{
-	/* Isolate the SMT bit(s) in the APICID and check for 0 */
-	u32 mask = (1U << (fls(smp_num_siblings) - 1)) - 1;
-
-	if (smp_num_siblings == 1 || !(apicid & mask))
-		cpumask_set_cpu(cpu, &__cpu_primary_thread_mask);
-}
-
-/*
- * Due to the utter mess of CPUID evaluation smp_num_siblings is not valid
- * during early boot. Initialize the primary thread mask before SMP
- * bringup.
- */
-static int __init smp_init_primary_thread_mask(void)
-{
-	unsigned int cpu;
-
-	/*
-	 * XEN/PV provides either none or useless topology information.
-	 * Pretend that all vCPUs are primary threads.
-	 */
-	if (xen_pv_domain()) {
-		cpumask_copy(&__cpu_primary_thread_mask, cpu_possible_mask);
-		return 0;
-	}
-
-	for (cpu = 0; cpu < nr_logical_cpuids; cpu++)
-		cpu_mark_primary_thread(cpu, cpuid_to_apicid[cpu]);
-	return 0;
-}
-early_initcall(smp_init_primary_thread_mask);
-#else
-static inline void cpu_mark_primary_thread(unsigned int cpu, unsigned int apicid) { }
-#endif
-
-/*
- * Should use this API to allocate logical CPU IDs to keep nr_logical_cpuids
- * and cpuid_to_apicid[] synchronized.
- */
-static int allocate_logical_cpuid(int apicid)
-{
-	int i;
-
-	/*
-	 * cpuid <-> apicid mapping is persistent, so when a cpu is up,
-	 * check if the kernel has allocated a cpuid for it.
-	 */
-	for (i = 0; i < nr_logical_cpuids; i++) {
-		if (cpuid_to_apicid[i] == apicid)
-			return i;
-	}
-
-	/* Allocate a new cpuid. */
-	if (nr_logical_cpuids >= nr_cpu_ids) {
-		WARN_ONCE(1, "APIC: NR_CPUS/possible_cpus limit of %u reached. "
-			     "Processor %d/0x%x and the rest are ignored.\n",
-			     nr_cpu_ids, nr_logical_cpuids, apicid);
-		return -EINVAL;
-	}
-
-	cpuid_to_apicid[nr_logical_cpuids] = apicid;
-	return nr_logical_cpuids++;
-}
-
-static void cpu_update_apic(int cpu, u32 apicid)
-{
-#if defined(CONFIG_SMP) || defined(CONFIG_X86_64)
-	early_per_cpu(x86_cpu_to_apicid, cpu) = apicid;
-#endif
-	set_cpu_possible(cpu, true);
-	physid_set(apicid, phys_cpu_present_map);
-	set_cpu_present(cpu, true);
-	num_processors++;
-
-	if (system_state != SYSTEM_BOOTING)
-		cpu_mark_primary_thread(cpu, apicid);
-}
-
-static __init void cpu_set_boot_apic(void)
-{
-	cpuid_to_apicid[0] = boot_cpu_physical_apicid;
-	cpu_update_apic(0, boot_cpu_physical_apicid);
-	x86_32_probe_bigsmp_early();
-}
-
-int generic_processor_info(int apicid)
-{
-	int cpu, max = nr_cpu_ids;
-
-	/* The boot CPU must be set before MADT/MPTABLE parsing happens */
-	if (cpuid_to_apicid[0] == BAD_APICID)
-		panic("Boot CPU APIC not registered yet\n");
-
-	if (apicid == boot_cpu_physical_apicid)
-		return 0;
-
-	if (disabled_cpu_apicid == apicid) {
-		int thiscpu = num_processors + disabled_cpus;
-
-		pr_warn("APIC: Disabling requested cpu. Processor %d/0x%x ignored.\n",
-			thiscpu, apicid);
-
-		disabled_cpus++;
-		return -ENODEV;
-	}
-
-	if (num_processors >= nr_cpu_ids) {
-		int thiscpu = max + disabled_cpus;
-
-		pr_warn("APIC: NR_CPUS/possible_cpus limit of %i reached. "
-			"Processor %d/0x%x ignored.\n", max, thiscpu, apicid);
-
-		disabled_cpus++;
-		return -EINVAL;
-	}
-
-	cpu = allocate_logical_cpuid(apicid);
-	if (cpu < 0) {
-		disabled_cpus++;
-		return -EINVAL;
-	}
-
-	cpu_update_apic(cpu, apicid);
-	return cpu;
-}
-
-
 void __irq_msi_compose_msg(struct irq_cfg *cfg, struct msi_msg *msg,
 			   bool dmar)
 {
···
 
 static void __init apic_bsp_up_setup(void)
 {
-#ifdef CONFIG_X86_64
-	apic_write(APIC_ID, apic->set_apic_id(boot_cpu_physical_apicid));
-#endif
-	physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
+	reset_phys_cpu_present_map(boot_cpu_physical_apicid);
 }
 
 /**
···
  * that is using request_resource
  */
 late_initcall(lapic_insert_resource);
-
-static int __init apic_set_disabled_cpu_apicid(char *arg)
-{
-	if (!arg || !get_option(&arg, &disabled_cpu_apicid))
-		return -EINVAL;
-
-	return 0;
-}
-early_param("disable_cpu_apicid", apic_set_disabled_cpu_apicid);
 
 static int __init apic_set_extnmi(char *arg)
 {

arch/x86/kernel/apic/apic_common.c

···
 	return 1U << cpu;
 }
 
-bool default_check_apicid_used(physid_mask_t *map, u32 apicid)
-{
-	return physid_isset(apicid, *map);
-}
-
-void default_ioapic_phys_id_map(physid_mask_t *phys_map, physid_mask_t *retmap)
-{
-	*retmap = *phys_map;
-}
-
 u32 default_cpu_present_to_apicid(int mps_cpu)
 {
 	if (mps_cpu < nr_cpu_ids && cpu_present(mps_cpu))
···
 		return BAD_APICID;
 }
 EXPORT_SYMBOL_GPL(default_cpu_present_to_apicid);
-
-bool default_apic_id_registered(void)
-{
-	return physid_isset(read_apic_id(), phys_cpu_present_map);
-}
 
 /*
  * Set up the logical destination ID when the APIC operates in logical

arch/x86/kernel/apic/apic_flat_64.c

···
 	return (x >> 24) & 0xFF;
 }
 
-static u32 set_apic_id(u32 id)
-{
-	return (id & 0xFF) << 24;
-}
-
-static u32 flat_phys_pkg_id(u32 initial_apic_id, int index_msb)
-{
-	return initial_apic_id >> index_msb;
-}
-
 static int flat_probe(void)
 {
 	return 1;
···
 	.name				= "flat",
 	.probe				= flat_probe,
 	.acpi_madt_oem_check		= flat_acpi_madt_oem_check,
-	.apic_id_registered		= default_apic_id_registered,
 
 	.dest_mode_logical		= true,
 
···
 
 	.init_apic_ldr			= default_init_apic_ldr,
 	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
-	.phys_pkg_id			= flat_phys_pkg_id,
 
 	.max_apic_id			= 0xFE,
 	.get_apic_id			= flat_get_apic_id,
-	.set_apic_id			= set_apic_id,
 
 	.calc_dest_apicid		= apic_flat_calc_apicid,
 
···
 	.name				= "physical flat",
 	.probe				= physflat_probe,
 	.acpi_madt_oem_check		= physflat_acpi_madt_oem_check,
-	.apic_id_registered		= default_apic_id_registered,
 
 	.dest_mode_logical		= false,
 
 	.disable_esr			= 0,
 
 	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
-	.phys_pkg_id			= flat_phys_pkg_id,
 
 	.max_apic_id			= 0xFE,
 	.get_apic_id			= flat_get_apic_id,
-	.set_apic_id			= set_apic_id,
 
 	.calc_dest_apicid		= apic_default_calc_apicid,
 

arch/x86/kernel/apic/apic_noop.c

···
 static void noop_apic_icr_write(u32 low, u32 id) { }
 static int noop_wakeup_secondary_cpu(u32 apicid, unsigned long start_eip) { return -1; }
 static u64 noop_apic_icr_read(void) { return 0; }
-static u32 noop_phys_pkg_id(u32 cpuid_apic, int index_msb) { return 0; }
 static u32 noop_get_apic_id(u32 apicid) { return 0; }
 static void noop_apic_eoi(void) { }
 
···
 
 	.disable_esr			= 0,
 
-	.check_apicid_used		= default_check_apicid_used,
-	.ioapic_phys_id_map		= default_ioapic_phys_id_map,
 	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
-
-	.phys_pkg_id			= noop_phys_pkg_id,
 
 	.max_apic_id			= 0xFE,
 	.get_apic_id			= noop_get_apic_id,

arch/x86/kernel/apic/apic_numachip.c

···
 	return id;
 }
 
-static u32 numachip1_set_apic_id(u32 id)
-{
-	return (id & 0xff) << 24;
-}
-
 static u32 numachip2_get_apic_id(u32 x)
 {
 	u64 mcfg;
 
 	rdmsrl(MSR_FAM10H_MMIO_CONF_BASE, mcfg);
 	return ((mcfg >> (28 - 8)) & 0xfff00) | (x >> 24);
-}
-
-static u32 numachip2_set_apic_id(u32 id)
-{
-	return id << 24;
-}
-
-static u32 numachip_phys_pkg_id(u32 initial_apic_id, int index_msb)
-{
-	return initial_apic_id >> index_msb;
 }
 
 static void numachip1_apic_icr_write(int apicid, unsigned int val)
···
 	.disable_esr			= 0,
 
 	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
-	.phys_pkg_id			= numachip_phys_pkg_id,
 
 	.max_apic_id			= UINT_MAX,
 	.get_apic_id			= numachip1_get_apic_id,
-	.set_apic_id			= numachip1_set_apic_id,
 
 	.calc_dest_apicid		= apic_default_calc_apicid,
 
···
 	.disable_esr			= 0,
 
 	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
-	.phys_pkg_id			= numachip_phys_pkg_id,
 
 	.max_apic_id			= UINT_MAX,
 	.get_apic_id			= numachip2_get_apic_id,
-	.set_apic_id			= numachip2_set_apic_id,
 
 	.calc_dest_apicid		= apic_default_calc_apicid,
 

arch/x86/kernel/apic/bigsmp_32.c

···
 	return (x >> 24) & 0xFF;
 }
 
-static bool bigsmp_check_apicid_used(physid_mask_t *map, u32 apicid)
-{
-	return false;
-}
-
-static void bigsmp_ioapic_phys_id_map(physid_mask_t *phys_map, physid_mask_t *retmap)
-{
-	/* For clustered we don't have a good way to do this yet - hack */
-	physids_promote(0xFFL, retmap);
-}
-
-static u32 bigsmp_phys_pkg_id(u32 cpuid_apic, int index_msb)
-{
-	return cpuid_apic >> index_msb;
-}
-
 static void bigsmp_send_IPI_allbutself(int vector)
 {
 	default_send_IPI_mask_allbutself_phys(cpu_online_mask, vector);
···
 
 	.disable_esr			= 1,
 
-	.check_apicid_used		= bigsmp_check_apicid_used,
-	.ioapic_phys_id_map		= bigsmp_ioapic_phys_id_map,
 	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
-	.phys_pkg_id			= bigsmp_phys_pkg_id,
 
 	.max_apic_id			= 0xFE,
 	.get_apic_id			= bigsmp_get_apic_id,
-	.set_apic_id			= NULL,
 
 	.calc_dest_apicid		= apic_default_calc_apicid,
 

arch/x86/kernel/apic/io_apic.c

···
  *
  * by Matt Domsch <[e-mail]>  Tue Dec 21 12:25:05 CST 1999
  */
-void __init setup_ioapic_ids_from_mpc_nocheck(void)
+static void __init setup_ioapic_ids_from_mpc_nocheck(void)
 {
+	DECLARE_BITMAP(phys_id_present_map, MAX_LOCAL_APIC);
+	const u32 broadcast_id = 0xF;
 	union IO_APIC_reg_00 reg_00;
-	physid_mask_t phys_id_present_map;
-	int ioapic_idx;
-	int i;
 	unsigned char old_id;
 	unsigned long flags;
+	int ioapic_idx, i;
 
 	/*
 	 * This is broken; anything with a real cpu count has to
 	 * circumvent this idiocy regardless.
 	 */
-	apic->ioapic_phys_id_map(&phys_cpu_present_map, &phys_id_present_map);
+	copy_phys_cpu_present_map(phys_id_present_map);
 
 	/*
 	 * Set the IOAPIC ID to the value stored in the MPC table.
···
 
 		old_id = mpc_ioapic_id(ioapic_idx);
 
-		if (mpc_ioapic_id(ioapic_idx) >= get_physical_broadcast()) {
-			printk(KERN_ERR "BIOS bug, IO-APIC#%d ID is %d in the MPC table!...\n",
-				ioapic_idx, mpc_ioapic_id(ioapic_idx));
-			printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
-				reg_00.bits.ID);
+		if (mpc_ioapic_id(ioapic_idx) >= broadcast_id) {
+			pr_err(FW_BUG "IO-APIC#%d ID is %d in the MPC table!...\n",
+			       ioapic_idx, mpc_ioapic_id(ioapic_idx));
+			pr_err("... fixing up to %d. (tell your hw vendor)\n", reg_00.bits.ID);
 			ioapics[ioapic_idx].mp_config.apicid = reg_00.bits.ID;
 		}
 
···
 		 * system must have a unique ID or we get lots of nice
 		 * 'stuck on smp_invalidate_needed IPI wait' messages.
 		 */
-		if (apic->check_apicid_used(&phys_id_present_map,
-					    mpc_ioapic_id(ioapic_idx))) {
-			printk(KERN_ERR "BIOS bug, IO-APIC#%d ID %d is already used!...\n",
-				ioapic_idx, mpc_ioapic_id(ioapic_idx));
-			for (i = 0; i < get_physical_broadcast(); i++)
-				if (!physid_isset(i, phys_id_present_map))
+		if (test_bit(mpc_ioapic_id(ioapic_idx), phys_id_present_map)) {
+			pr_err(FW_BUG "IO-APIC#%d ID %d is already used!...\n",
+			       ioapic_idx, mpc_ioapic_id(ioapic_idx));
+			for (i = 0; i < broadcast_id; i++)
+				if (!test_bit(i, phys_id_present_map))
 					break;
-			if (i >= get_physical_broadcast())
+			if (i >= broadcast_id)
 				panic("Max APIC ID exceeded!\n");
-			printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
-				i);
-			physid_set(i, phys_id_present_map);
+			pr_err("... fixing up to %d. (tell your hw vendor)\n", i);
+			set_bit(i, phys_id_present_map);
 			ioapics[ioapic_idx].mp_config.apicid = i;
 		} else {
 			apic_printk(APIC_VERBOSE, "Setting %d in the phys_id_present_map\n",
 				    mpc_ioapic_id(ioapic_idx));
-			physid_set(mpc_ioapic_id(ioapic_idx), phys_id_present_map);
+			set_bit(mpc_ioapic_id(ioapic_idx), phys_id_present_map);
 		}
 
 		/*
···
 	 * 8259A.
 	 */
 	if (pin1 == -1) {
-		panic_if_irq_remap("BIOS bug: timer not connected to IO-APIC");
+		panic_if_irq_remap(FW_BUG "Timer not connected to IO-APIC");
 		pin1 = pin2;
 		apic1 = apic2;
 		no_pin1 = 1;
···
 #ifdef CONFIG_X86_32
 static int io_apic_get_unique_id(int ioapic, int apic_id)
 {
+	static DECLARE_BITMAP(apic_id_map, MAX_LOCAL_APIC);
+	const u32 broadcast_id = 0xF;
 	union IO_APIC_reg_00 reg_00;
-	static physid_mask_t apic_id_map = PHYSID_MASK_NONE;
-	physid_mask_t tmp;
 	unsigned long flags;
 	int i = 0;
 
-	/*
-	 * The P4 platform supports up to 256 APIC IDs on two separate APIC
-	 * buses (one for LAPICs, one for IOAPICs), where predecessors only
-	 * supports up to 16 on one shared APIC bus.
-	 *
-	 * TBD: Expand LAPIC/IOAPIC support on P4-class systems to take full
-	 *      advantage of new APIC bus architecture.
-	 */
-
-	if (physids_empty(apic_id_map))
-		apic->ioapic_phys_id_map(&phys_cpu_present_map, &apic_id_map);
+	/* Initialize the ID map */
+	if (bitmap_empty(apic_id_map, MAX_LOCAL_APIC))
+		copy_phys_cpu_present_map(apic_id_map);
 
 	raw_spin_lock_irqsave(&ioapic_lock, flags);
 	reg_00.raw = io_apic_read(ioapic, 0);
 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 
-	if (apic_id >= get_physical_broadcast()) {
-		printk(KERN_WARNING "IOAPIC[%d]: Invalid apic_id %d, trying "
-			"%d\n", ioapic, apic_id, reg_00.bits.ID);
+	if (apic_id >= broadcast_id) {
+		pr_warn("IOAPIC[%d]: Invalid apic_id %d, trying %d\n",
+			ioapic, apic_id, reg_00.bits.ID);
 		apic_id = reg_00.bits.ID;
 	}
 
-	/*
-	 * Every APIC in a system must have a unique ID or we get lots of nice
-	 * 'stuck on smp_invalidate_needed IPI wait' messages.
-	 */
-	if (apic->check_apicid_used(&apic_id_map, apic_id)) {
-
-		for (i = 0; i < get_physical_broadcast(); i++) {
-			if (!apic->check_apicid_used(&apic_id_map, i))
+	/* Every APIC in a system must have a unique ID */
+	if (test_bit(apic_id, apic_id_map)) {
+		for (i = 0; i < broadcast_id; i++) {
+			if (!test_bit(i, apic_id_map))
 				break;
 		}
 
-		if (i == get_physical_broadcast())
+		if (i == broadcast_id)
 			panic("Max apic_id exceeded!\n");
 
-		printk(KERN_WARNING "IOAPIC[%d]: apic_id %d already used, "
-			"trying %d\n", ioapic, apic_id, i);
-
+		pr_warn("IOAPIC[%d]: apic_id %d already used, trying %d\n", ioapic, apic_id, i);
 		apic_id = i;
 	}
 
-	physid_set_mask_of_physid(apic_id, &tmp);
-	physids_or(apic_id_map, apic_id_map, tmp);
+	set_bit(apic_id, apic_id_map);
 
 	if (reg_00.bits.ID != apic_id) {
 		reg_00.bits.ID = apic_id;
···
 
 static u8 io_apic_unique_id(int idx, u8 id)
 {
-	if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
-	    !APIC_XAPIC(boot_cpu_apic_version))
+	if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) && !APIC_XAPIC(boot_cpu_apic_version))
 		return io_apic_get_unique_id(idx, id);
-	else
-		return id;
+	return id;
 }
 #else
 static u8 io_apic_unique_id(int idx, u8 id)

arch/x86/kernel/apic/local.h

···
 /* X2APIC */
 void __x2apic_send_IPI_dest(unsigned int apicid, int vector, unsigned int dest);
 u32 x2apic_get_apic_id(u32 id);
-u32 x2apic_set_apic_id(u32 id);
-u32 x2apic_phys_pkg_id(u32 initial_apicid, int index_msb);
 
 void x2apic_send_IPI_all(int vector);
 void x2apic_send_IPI_allbutself(int vector);
···
 void default_send_IPI_allbutself(int vector);
 void default_send_IPI_all(int vector);
 void default_send_IPI_self(int vector);
-
-bool default_apic_id_registered(void);
-bool default_check_apicid_used(physid_mask_t *map, u32 apicid);
 
 #ifdef CONFIG_X86_32
 void default_send_IPI_mask_sequence_logical(const struct cpumask *mask, int vector);

arch/x86/kernel/apic/probe_32.c

···
 
 #include "local.h"
 
-static u32 default_phys_pkg_id(u32 cpuid_apic, int index_msb)
-{
-	return cpuid_apic >> index_msb;
-}
-
 static u32 default_get_apic_id(u32 x)
 {
 	unsigned int ver = GET_APIC_VERSION(apic_read(APIC_LVR));
···
 
 	.name				= "default",
 	.probe				= probe_default,
-	.apic_id_registered		= default_apic_id_registered,
 
 	.dest_mode_logical		= true,
 
 	.disable_esr			= 0,
 
-	.check_apicid_used		= default_check_apicid_used,
 	.init_apic_ldr			= default_init_apic_ldr,
-	.ioapic_phys_id_map		= default_ioapic_phys_id_map,
 	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
-	.phys_pkg_id			= default_phys_pkg_id,
 
 	.max_apic_id			= 0xFE,
 	.get_apic_id			= default_get_apic_id,

arch/x86/kernel/apic/x2apic_cluster.c

···
 
 	.disable_esr			= 0,
 
-	.check_apicid_used		= NULL,
 	.init_apic_ldr			= init_x2apic_ldr,
-	.ioapic_phys_id_map		= NULL,
 	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
-	.phys_pkg_id			= x2apic_phys_pkg_id,
 
 	.max_apic_id			= UINT_MAX,
 	.x2apic_set_max_apicid		= true,
 	.get_apic_id			= x2apic_get_apic_id,
-	.set_apic_id			= x2apic_set_apic_id,
 
 	.calc_dest_apicid		= x2apic_calc_apicid,
 

arch/x86/kernel/apic/x2apic_phys.c

···
 	return id;
 }
 
-u32 x2apic_set_apic_id(u32 id)
-{
-	return id;
-}
-
-u32 x2apic_phys_pkg_id(u32 initial_apicid, int index_msb)
-{
-	return initial_apicid >> index_msb;
-}
-
 static struct apic apic_x2apic_phys __ro_after_init = {
 
 	.name				= "physical x2apic",
···
 	.disable_esr			= 0,
 
 	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
-	.phys_pkg_id			= x2apic_phys_pkg_id,
 
 	.max_apic_id			= UINT_MAX,
 	.x2apic_set_max_apicid		= true,
 	.get_apic_id			= x2apic_get_apic_id,
-	.set_apic_id			= x2apic_set_apic_id,
 
 	.calc_dest_apicid		= apic_default_calc_apicid,
 

arch/x86/kernel/apic/x2apic_uv_x.c

···
 	is_uv(UV3) ? sname.s3.field :		\
 	undef)
 
-/* [Copied from arch/x86/kernel/cpu/topology.c:detect_extended_topology()] */
-
-#define SMT_LEVEL			0	/* Leaf 0xb SMT level */
-#define INVALID_TYPE			0	/* Leaf 0xb sub-leaf types */
-#define SMT_TYPE			1
-#define CORE_TYPE			2
-#define LEAFB_SUBTYPE(ecx)		(((ecx) >> 8) & 0xff)
-#define BITS_SHIFT_NEXT_LEVEL(eax)	((eax) & 0x1f)
-
-static void set_x2apic_bits(void)
-{
-	unsigned int eax, ebx, ecx, edx, sub_index;
-	unsigned int sid_shift;
-
-	cpuid(0, &eax, &ebx, &ecx, &edx);
-	if (eax < 0xb) {
-		pr_info("UV: CPU does not have CPUID.11\n");
-		return;
-	}
-
-	cpuid_count(0xb, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
-	if (ebx == 0 || (LEAFB_SUBTYPE(ecx) != SMT_TYPE)) {
-		pr_info("UV: CPUID.11 not implemented\n");
-		return;
-	}
-
-	sid_shift = BITS_SHIFT_NEXT_LEVEL(eax);
-	sub_index = 1;
-	do {
-		cpuid_count(0xb, sub_index, &eax, &ebx, &ecx, &edx);
-		if (LEAFB_SUBTYPE(ecx) == CORE_TYPE) {
-			sid_shift = BITS_SHIFT_NEXT_LEVEL(eax);
-			break;
-		}
-		sub_index++;
-	} while (LEAFB_SUBTYPE(ecx) != INVALID_TYPE);
-
-	uv_cpuid.apicid_shift	= 0;
-	uv_cpuid.apicid_mask	= (~(-1 << sid_shift));
-	uv_cpuid.socketid_shift = sid_shift;
-}
-
 static void __init early_get_apic_socketid_shift(void)
 {
+	unsigned int sid_shift = topology_get_domain_shift(TOPO_PKG_DOMAIN);
+
 	if (is_uv2_hub() || is_uv3_hub())
 		uvh_apicid.v = uv_early_read_mmr(UVH_APICID);
 
-	set_x2apic_bits();
+	if (sid_shift) {
+		uv_cpuid.apicid_shift	= 0;
+		uv_cpuid.apicid_mask	= (~(-1 << sid_shift));
+		uv_cpuid.socketid_shift = sid_shift;
+	} else {
+		pr_info("UV: CPU does not have valid CPUID.11\n");
+	}
 
 	pr_info("UV: apicid_shift:%d apicid_mask:0x%x\n", uv_cpuid.apicid_shift, uv_cpuid.apicid_mask);
 	pr_info("UV: socketid_shift:%d pnode_mask:0x%x\n", uv_cpuid.socketid_shift, uv_cpuid.pnode_mask);
···
 	uv_send_IPI_mask(cpu_online_mask, vector);
 }
 
-static u32 set_apic_id(u32 id)
-{
-	return id;
-}
-
-static unsigned int uv_read_apic_id(void)
-{
-	return x2apic_get_apic_id(apic_read(APIC_ID));
-}
-
-static u32 uv_phys_pkg_id(u32 initial_apicid, int index_msb)
-{
-	return uv_read_apic_id() >> index_msb;
-}
-
 static int uv_probe(void)
 {
 	return apic == &apic_x2apic_uv_x;
···
 	.disable_esr			= 0,
 
 	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
-	.phys_pkg_id			= uv_phys_pkg_id,
 
 	.max_apic_id			= UINT_MAX,
 	.get_apic_id			= x2apic_get_apic_id,
-	.set_apic_id			= set_apic_id,
 
 	.calc_dest_apicid		= apic_default_calc_apicid,
 

arch/x86/kernel/cpu/Makefile

···
 # As above, instrumenting secondary CPU boot code causes boot hangs.
 KCSAN_SANITIZE_common.o := n
 
-obj-y			:= cacheinfo.o scattered.o topology.o
+obj-y			:= cacheinfo.o scattered.o
+obj-y			+= topology_common.o topology_ext.o topology_amd.o
 obj-y			+= common.o
 obj-y			+= rdrand.o
 obj-y			+= match.o
···
 obj-y			+= aperfmperf.o
 obj-y			+= cpuid-deps.o
 obj-y			+= umwait.o
+obj-y 			+= capflags.o powerflags.o
 
-obj-$(CONFIG_PROC_FS)	+= proc.o
-obj-y += capflags.o powerflags.o
+obj-$(CONFIG_X86_LOCAL_APIC)		+= topology.o
 
-obj-$(CONFIG_IA32_FEAT_CTL) += feat_ctl.o
+obj-$(CONFIG_PROC_FS)			+= proc.o
+
+obj-$(CONFIG_IA32_FEAT_CTL)		+= feat_ctl.o
 ifdef CONFIG_CPU_SUP_INTEL
-obj-y			+= intel.o intel_pconfig.o tsx.o
-obj-$(CONFIG_PM)	+= intel_epb.o
+obj-y					+= intel.o intel_pconfig.o tsx.o
+obj-$(CONFIG_PM)			+= intel_epb.o
 endif
 obj-$(CONFIG_CPU_SUP_AMD)		+= amd.o
 obj-$(CONFIG_CPU_SUP_HYGON)		+= hygon.o

arch/x86/kernel/cpu/amd.c

···
 
 #include "cpu.h"
 
-/*
- * nodes_per_socket: Stores the number of nodes per socket.
- * Refer to Fam15h Models 00-0fh BKDG - CPUID Fn8000_001E_ECX
- * Node Identifiers[10:8]
- */
-static u32 nodes_per_socket = 1;
-
 static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p)
 {
 	u32 gprs[8] = { 0 };
···
 }
 #endif
 
-/*
- * Fix up topo::core_id for pre-F17h systems to be in the
- * [0 .. cores_per_node - 1] range. Not really needed but
- * kept so as not to break existing setups.
- */
-static void legacy_fixup_core_id(struct cpuinfo_x86 *c)
-{
-	u32 cus_per_node;
-
-	if (c->x86 >= 0x17)
-		return;
-
-	cus_per_node = c->x86_max_cores / nodes_per_socket;
-	c->topo.core_id %= cus_per_node;
-}
-
-/*
- * Fixup core topology information for
- * (1) AMD multi-node processors
- *     Assumption: Number of cores in each internal node is the same.
- * (2) AMD processors supporting compute units
- */
-static void amd_get_topology(struct cpuinfo_x86 *c)
-{
-	/* get information required for multi-node processors */
-	if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
-		int err;
-		u32 eax, ebx, ecx, edx;
-
-		cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
-
-		c->topo.die_id  = ecx & 0xff;
-
-		if (c->x86 == 0x15)
-			c->topo.cu_id = ebx & 0xff;
-
-		if (c->x86 >= 0x17) {
-			c->topo.core_id = ebx & 0xff;
-
-			if (smp_num_siblings > 1)
-				c->x86_max_cores /= smp_num_siblings;
-		}
-
-		/*
-		 * In case leaf B is available, use it to derive
-		 * topology information.
-		 */
-		err = detect_extended_topology(c);
-		if (!err)
-			c->x86_coreid_bits = get_count_order(c->x86_max_cores);
-
-		cacheinfo_amd_init_llc_id(c);
-
-	} else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
-		u64 value;
-
-		rdmsrl(MSR_FAM10H_NODE_ID, value);
-		c->topo.die_id = value & 7;
-		c->topo.llc_id = c->topo.die_id;
-	} else
-		return;
-
-	if (nodes_per_socket > 1) {
-		set_cpu_cap(c, X86_FEATURE_AMD_DCM);
-		legacy_fixup_core_id(c);
-	}
-}
-
-/*
- * On a AMD dual core setup the lower bits of the APIC id distinguish the cores.
- * Assumes number of cores is a power of two.
- */
-static void amd_detect_cmp(struct cpuinfo_x86 *c)
-{
-	unsigned bits;
-
-	bits = c->x86_coreid_bits;
-	/* Low order bits define the core id (index of core in socket) */
-	c->topo.core_id = c->topo.initial_apicid & ((1 << bits)-1);
-	/* Convert the initial APIC ID into the socket ID */
-	c->topo.pkg_id = c->topo.initial_apicid >> bits;
-	/* use socket ID also for last level cache */
-	c->topo.llc_id = c->topo.die_id = c->topo.pkg_id;
-}
-
-u32 amd_get_nodes_per_socket(void)
-{
-	return nodes_per_socket;
-}
-EXPORT_SYMBOL_GPL(amd_get_nodes_per_socket);
-
 static void srat_detect_node(struct cpuinfo_x86 *c)
 {
 #ifdef CONFIG_NUMA
···
 #endif
 }
 
-static void early_init_amd_mc(struct cpuinfo_x86 *c)
-{
-#ifdef CONFIG_SMP
-	unsigned bits, ecx;
-
-	/* Multi core CPU? */
-	if (c->extended_cpuid_level < 0x80000008)
-		return;
-
-	ecx = cpuid_ecx(0x80000008);
-
-	c->x86_max_cores = (ecx & 0xff) + 1;
-
-	/* CPU telling us the core id bits shift? */
-	bits = (ecx >> 12) & 0xF;
-
-	/* Otherwise recompute */
-	if (bits == 0) {
-		while ((1 << bits) < c->x86_max_cores)
-			bits++;
-	}
-
-	c->x86_coreid_bits = bits;
-#endif
-}
-
 static void bsp_init_amd(struct cpuinfo_x86 *c)
 {
 	if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
···
 
 	if (cpu_has(c, X86_FEATURE_MWAITX))
 		use_mwaitx_delay();
-
-	if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
-		u32 ecx;
-
-		ecx = cpuid_ecx(0x8000001e);
-		__max_die_per_package = nodes_per_socket = ((ecx >> 8) & 7) + 1;
-	} else if (boot_cpu_has(X86_FEATURE_NODEID_MSR)) {
-		u64 value;
-
-		rdmsrl(MSR_FAM10H_NODE_ID, value);
-		__max_die_per_package = nodes_per_socket = ((value >> 3) & 7) + 1;
-	}
 
 	if (!boot_cpu_has(X86_FEATURE_AMD_SSBD) &&
 	    !boot_cpu_has(X86_FEATURE_VIRT_SSBD) &&
···
 	u64 value;
 	u32 dummy;
 
-	early_init_amd_mc(c);
-
 	if (c->x86 >= 0xf)
 		set_cpu_cap(c, X86_FEATURE_K8);
 
···
 			}
 		}
 	}
-
-	if (cpu_has(c, X86_FEATURE_TOPOEXT))
-		smp_num_siblings = ((cpuid_ebx(0x8000001e) >> 8) & 0xff) + 1;
 
 	if (!cpu_has(c, X86_FEATURE_HYPERVISOR) && !cpu_has(c, X86_FEATURE_IBPB_BRTYPE)) {
 		if (c->x86 == 0x17 && boot_cpu_has(X86_FEATURE_AMD_IBPB))
···
 	if (cpu_has(c, X86_FEATURE_FSRM))
 		set_cpu_cap(c, X86_FEATURE_FSRS);
 
-	/* get apicid instead of initial apic id from cpuid */
-	c->topo.apicid = read_apic_id();
-
 	/* K6s reports MCEs but don't actually have all the MSRs */
 	if (c->x86 < 6)
 		clear_cpu_cap(c, X86_FEATURE_MCE);
···
 
 	cpu_detect_cache_sizes(c);
 
-	amd_detect_cmp(c);
-	amd_get_topology(c);
 	srat_detect_node(c);
 
 	init_amd_cacheinfo(c);

arch/x86/kernel/cpu/cacheinfo.c

···
 	eax->split.type = types[leaf];
 	eax->split.level = levels[leaf];
 	eax->split.num_threads_sharing = 0;
-	eax->split.num_cores_on_die = __this_cpu_read(cpu_info.x86_max_cores) - 1;
+	eax->split.num_cores_on_die = topology_num_cores_per_package();
 
 
 	if (assoc == 0xffff)
···
 	if (index < 3)
 		return;
 
-	node = topology_die_id(smp_processor_id());
+	node = topology_amd_node_id(smp_processor_id());
 	this_leaf->nb = node_to_amd_nb(node);
 	if (this_leaf->nb && !this_leaf->nb->l3_cache.indices)
 		amd_calc_l3_indices(this_leaf->nb);
···
 	return i;
 }
 
-void cacheinfo_amd_init_llc_id(struct cpuinfo_x86 *c)
+void cacheinfo_amd_init_llc_id(struct cpuinfo_x86 *c, u16 die_id)
 {
 	/*
 	 * We may have multiple LLCs if L3 caches exist, so check if we
···
 
 	if (c->x86 < 0x17) {
 		/* LLC is at the node level. */
-		c->topo.llc_id = c->topo.die_id;
+		c->topo.llc_id = die_id;
 	} else if (c->x86 == 0x17 && c->x86_model <= 0x1F) {
 		/*
 		 * LLC is at the core complex level.

arch/x86/kernel/cpu/centaur.c

···
 #endif
 	early_init_centaur(c);
 	init_intel_cacheinfo(c);
-	detect_num_cpu_cores(c);
-#ifdef CONFIG_X86_32
-	detect_ht(c);
-#endif
 
 	if (c->cpuid_level > 9) {
 		unsigned int eax = cpuid_eax(10);

arch/x86/kernel/cpu/common.c

···
 u32 elf_hwcap2 __read_mostly;
 
 /* Number of siblings per CPU package */
-int smp_num_siblings = 1;
-EXPORT_SYMBOL(smp_num_siblings);
+unsigned int __max_threads_per_core __ro_after_init = 1;
+EXPORT_SYMBOL(__max_threads_per_core);
+
+unsigned int __max_dies_per_package __ro_after_init = 1;
+EXPORT_SYMBOL(__max_dies_per_package);
+
+unsigned int __max_logical_packages __ro_after_init = 1;
+EXPORT_SYMBOL(__max_logical_packages);
+
+unsigned int __num_cores_per_package __ro_after_init = 1;
+EXPORT_SYMBOL(__num_cores_per_package);
+
+unsigned int __num_threads_per_package __ro_after_init = 1;
+EXPORT_SYMBOL(__num_threads_per_package);
 
 static struct ppin_info {
 	int	feature;
···
 	*(s + 1) = '\0';
 }
 
-void detect_num_cpu_cores(struct cpuinfo_x86 *c)
-{
-	unsigned int eax, ebx, ecx, edx;
-
-	c->x86_max_cores = 1;
-	if (!IS_ENABLED(CONFIG_SMP) || c->cpuid_level < 4)
-		return;
-
-	cpuid_count(4, 0, &eax, &ebx, &ecx, &edx);
-	if (eax & 0x1f)
-		c->x86_max_cores = (eax >> 26) + 1;
-}
-
 void cpu_detect_cache_sizes(struct cpuinfo_x86 *c)
 {
 	unsigned int n, dummy, ebx, ecx, edx, l2size;
···
 	pr_info("Last level dTLB entries: 4KB %d, 2MB %d, 4MB %d, 1GB %d\n",
 		tlb_lld_4k[ENTRIES], tlb_lld_2m[ENTRIES],
 		tlb_lld_4m[ENTRIES], tlb_lld_1g[ENTRIES]);
-}
-
-int detect_ht_early(struct cpuinfo_x86 *c)
-{
-#ifdef CONFIG_SMP
-	u32 eax, ebx, ecx, edx;
-
-	if (!cpu_has(c, X86_FEATURE_HT))
-		return -1;
-
-	if (cpu_has(c, X86_FEATURE_CMP_LEGACY))
-		return -1;
-
-	if (cpu_has(c, X86_FEATURE_XTOPOLOGY))
-		return -1;
-
-	cpuid(1, &eax, &ebx, &ecx, &edx);
-
-	smp_num_siblings = (ebx & 0xff0000) >> 16;
-	if (smp_num_siblings == 1)
-		pr_info_once("CPU0: Hyper-Threading is disabled\n");
-#endif
-	return 0;
-}
-
-void detect_ht(struct cpuinfo_x86 *c)
-{
-#ifdef CONFIG_SMP
-	int index_msb, core_bits;
-
-	if (detect_ht_early(c) < 0)
-		return;
-
-	index_msb = get_count_order(smp_num_siblings);
-	c->topo.pkg_id = apic->phys_pkg_id(c->topo.initial_apicid, index_msb);
-
-	smp_num_siblings = smp_num_siblings / c->x86_max_cores;
-
-	index_msb = get_count_order(smp_num_siblings);
-
-	core_bits = get_count_order(c->x86_max_cores);
-
-	c->topo.core_id = apic->phys_pkg_id(c->topo.initial_apicid, index_msb) &
-		((1 << core_bits) - 1);
-#endif
 }
 
 static void get_cpu_vendor(struct cpuinfo_x86 *c)
···
 		get_cpu_address_sizes(c);
 		cpu_parse_early_param();
 
+		cpu_init_topology(c);
+
 		if (this_cpu->c_early_init)
 			this_cpu->c_early_init(c);
 
···
 	} else {
 		setup_clear_cpu_cap(X86_FEATURE_CPUID);
 		get_cpu_address_sizes(c);
+		cpu_init_topology(c);
 	}
 
 	setup_force_cpu_cap(X86_FEATURE_ALWAYS);
···
 
 	get_cpu_address_sizes(c);
 
-	if (c->cpuid_level >= 0x00000001) {
-		c->topo.initial_apicid = (cpuid_ebx(1) >> 24) & 0xFF;
-#ifdef CONFIG_X86_32
-# ifdef CONFIG_SMP
-		c->topo.apicid = apic->phys_pkg_id(c->topo.initial_apicid, 0);
-# else
-		c->topo.apicid = c->topo.initial_apicid;
-# endif
-#endif
-		c->topo.pkg_id = c->topo.initial_apicid;
-	}
-
 	get_model_name(c); /* Default name */
 
 	/*
···
 }
 
 /*
- * Validate that ACPI/mptables have the same information about the
- * effective APIC id and update the package map.
- */
-static void validate_apic_and_package_id(struct cpuinfo_x86 *c)
-{
-#ifdef CONFIG_SMP
-	unsigned int cpu = smp_processor_id();
-	u32 apicid;
-
-	apicid = apic->cpu_present_to_apicid(cpu);
-
-	if (apicid != c->topo.apicid) {
-		pr_err(FW_BUG "CPU%u: APIC id mismatch. Firmware: %x APIC: %x\n",
-		       cpu, apicid, c->topo.initial_apicid);
-	}
-	BUG_ON(topology_update_package_map(c->topo.pkg_id, cpu));
-	BUG_ON(topology_update_die_map(c->topo.die_id, cpu));
-#else
-	c->topo.logical_pkg_id = 0;
-#endif
-}
-
-/*
  * This does the hard work of actually picking apart the CPU stuff...
  */
 static void identify_cpu(struct cpuinfo_x86 *c)
···
 	c->x86_model = c->x86_stepping = 0;	/* So far unknown... */
 	c->x86_vendor_id[0] = '\0'; /* Unset */
 	c->x86_model_id[0] = '\0';  /* Unset */
-	c->x86_max_cores = 1;
-	c->x86_coreid_bits = 0;
-	c->topo.cu_id = 0xff;
-	c->topo.llc_id = BAD_APICID;
-	c->topo.l2c_id = BAD_APICID;
 #ifdef CONFIG_X86_64
 	c->x86_clflush_size = 64;
 	c->x86_phys_bits = 36;
···
 
 	generic_identify(c);
 
+	cpu_parse_topology(c);
+
 	if (this_cpu->c_identify)
 		this_cpu->c_identify(c);
 
 	/* Clear/Set all flags overridden by options, after probe */
 	apply_forced_caps(c);
-
-#ifdef CONFIG_X86_64
-	c->topo.apicid = apic->phys_pkg_id(c->topo.initial_apicid, 0);
-#endif
-
 
 	/*
 	 * Set default APIC and TSC_DEADLINE MSR fencing flag. AMD and
···
 			sprintf(c->x86_model_id, "%02x/%02x",
 				c->x86, c->x86_model);
 	}
-
-#ifdef CONFIG_X86_64
-	detect_ht(c);
-#endif
 
 	x86_init_rdrand(c);
 	setup_pku(c);
···
 #ifdef CONFIG_X86_32
 	enable_sep_cpu();
 #endif
-	validate_apic_and_package_id(c);
 	x86_spec_ctrl_setup_ap();
 	update_srbds_msr();
 	if (boot_cpu_has_bug(X86_BUG_GDS))
···
 	 * identify_boot_cpu() initialized SMT support information, let the
 	 * core code know.
 	 */
-	cpu_smt_set_num_threads(smp_num_siblings, smp_num_siblings);
+	cpu_smt_set_num_threads(__max_threads_per_core, __max_threads_per_core);
 
 	if (!IS_ENABLED(CONFIG_SMP)) {
 		pr_info("CPU: ");

arch/x86/kernel/cpu/cpu.h

···
 #ifndef ARCH_X86_CPU_H
 #define ARCH_X86_CPU_H
 
+#include <asm/cpu.h>
+#include <asm/topology.h>
+
+#include "topology.h"
+
 /* attempt to consolidate cpu attributes */
 struct cpu_dev {
 	const char	*c_vendor;
···
 extern void init_amd_cacheinfo(struct cpuinfo_x86 *c);
 extern void init_hygon_cacheinfo(struct cpuinfo_x86 *c);
 
-extern void detect_num_cpu_cores(struct cpuinfo_x86 *c);
-extern int detect_extended_topology_early(struct cpuinfo_x86 *c);
-extern int detect_extended_topology(struct cpuinfo_x86 *c);
-extern int detect_ht_early(struct cpuinfo_x86 *c);
-extern void detect_ht(struct cpuinfo_x86 *c);
 extern void check_null_seg_clears_base(struct cpuinfo_x86 *c);
 
-void cacheinfo_amd_init_llc_id(struct cpuinfo_x86 *c);
+void cacheinfo_amd_init_llc_id(struct cpuinfo_x86 *c, u16 die_id);
 void cacheinfo_hygon_init_llc_id(struct cpuinfo_x86 *c);
 
 unsigned int aperfmperf_get_khz(int cpu);
···
 	       mode == SPECTRE_V2_EIBRS_RETPOLINE ||
 	       mode == SPECTRE_V2_EIBRS_LFENCE;
 }
+
 #endif /* ARCH_X86_CPU_H */

arch/x86/kernel/cpu/debugfs.c

···
 #include <asm/apic.h>
 #include <asm/processor.h>
 
+#include "cpu.h"
+
 static int cpu_debug_show(struct seq_file *m, void *p)
 {
 	unsigned long cpu = (unsigned long)m->private;
···
 	seq_printf(m, "logical_die_id:      %u\n", c->topo.logical_die_id);
 	seq_printf(m, "llc_id:              %u\n", c->topo.llc_id);
 	seq_printf(m, "l2c_id:              %u\n", c->topo.l2c_id);
-	seq_printf(m, "max_cores:           %u\n", c->x86_max_cores);
-	seq_printf(m, "max_die_per_pkg:     %u\n", __max_die_per_package);
-	seq_printf(m, "smp_num_siblings:    %u\n", smp_num_siblings);
+	seq_printf(m, "amd_node_id:         %u\n", c->topo.amd_node_id);
+	seq_printf(m, "amd_nodes_per_pkg:   %u\n", topology_amd_nodes_per_pkg());
+	seq_printf(m, "num_threads:         %u\n", __num_threads_per_package);
+	seq_printf(m, "num_cores:           %u\n", __num_cores_per_package);
+	seq_printf(m, "max_dies_per_pkg:    %u\n", __max_dies_per_package);
+	seq_printf(m, "max_threads_per_core:%u\n", __max_threads_per_core);
 	return 0;
 }
 
···
 	.release	= single_release,
 };
 
+static int dom_debug_show(struct seq_file *m, void *p)
+{
+	static const char *domain_names[TOPO_MAX_DOMAIN] = {
+		[TOPO_SMT_DOMAIN]	= "Thread",
+		[TOPO_CORE_DOMAIN]	= "Core",
+		[TOPO_MODULE_DOMAIN]	= "Module",
+		[TOPO_TILE_DOMAIN]	= "Tile",
+		[TOPO_DIE_DOMAIN]	= "Die",
+		[TOPO_DIEGRP_DOMAIN]	= "DieGrp",
+		[TOPO_PKG_DOMAIN]	= "Package",
+	};
+	unsigned int dom, nthreads = 1;
+
+	for (dom = 0; dom < TOPO_MAX_DOMAIN; dom++) {
+		nthreads *= x86_topo_system.dom_size[dom];
+		seq_printf(m, "domain: %-10s shift: %u dom_size: %5u max_threads: %5u\n",
+			   domain_names[dom], x86_topo_system.dom_shifts[dom],
+			   x86_topo_system.dom_size[dom], nthreads);
+	}
+	return 0;
+}
+
+static int dom_debug_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, dom_debug_show, inode->i_private);
+}
+
+static const struct file_operations dfs_dom_ops = {
+	.open		= dom_debug_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
 static __init int cpu_init_debugfs(void)
 {
 	struct dentry *dir, *base = debugfs_create_dir("topo", arch_debugfs_dir);
 	unsigned long id;
 	char name[24];
+
+	debugfs_create_file("domains", 0444, base, NULL, &dfs_dom_ops);
 
 	dir = debugfs_create_dir("cpus", base);
 	for_each_possible_cpu(id) {

arch/x86/kernel/cpu/hygon.c

···
 
 #include "cpu.h"
 
-#define APICID_SOCKET_ID_BIT 6
-
-/*
- * nodes_per_socket: Stores the number of nodes per socket.
- * Refer to CPUID Fn8000_001E_ECX Node Identifiers[10:8]
- */
-static u32 nodes_per_socket = 1;
-
 #ifdef CONFIG_NUMA
 /*
  * To workaround broken NUMA config.  Read the comment in
···
 	return first_node(node_online_map); /* Shouldn't happen */
 }
 #endif
-
-static void hygon_get_topology_early(struct cpuinfo_x86 *c)
-{
-	if (cpu_has(c, X86_FEATURE_TOPOEXT))
-		smp_num_siblings = ((cpuid_ebx(0x8000001e) >> 8) & 0xff) + 1;
-}
-
-/*
- * Fixup core topology information for
- * (1) Hygon multi-node processors
- *     Assumption: Number of cores in each internal node is the same.
- * (2) Hygon processors supporting compute units
- */
-static void hygon_get_topology(struct cpuinfo_x86 *c)
-{
-	/* get information required for multi-node processors */
-	if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
-		int err;
-		u32 eax, ebx, ecx, edx;
-
-		cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
-
-		c->topo.die_id  = ecx & 0xff;
-
-		c->topo.core_id = ebx & 0xff;
-
-		if (smp_num_siblings > 1)
-			c->x86_max_cores /= smp_num_siblings;
-
-		/*
-		 * In case leaf B is available, use it to derive
-		 * topology information.
-		 */
-		err = detect_extended_topology(c);
-		if (!err)
-			c->x86_coreid_bits = get_count_order(c->x86_max_cores);
-
-		/*
-		 * Socket ID is ApicId[6] for the processors with model <= 0x3
-		 * when running on host.
-		 */
-		if (!boot_cpu_has(X86_FEATURE_HYPERVISOR) && c->x86_model <= 0x3)
-			c->topo.pkg_id = c->topo.apicid >> APICID_SOCKET_ID_BIT;
-
-		cacheinfo_hygon_init_llc_id(c);
-	} else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
-		u64 value;
-
-		rdmsrl(MSR_FAM10H_NODE_ID, value);
-		c->topo.die_id = value & 7;
-		c->topo.llc_id = c->topo.die_id;
-	} else
-		return;
-
-	if (nodes_per_socket > 1)
-		set_cpu_cap(c, X86_FEATURE_AMD_DCM);
-}
-
-/*
- * On Hygon setup the lower bits of the APIC id distinguish the cores.
- * Assumes number of cores is a power of two.
- */
-static void hygon_detect_cmp(struct cpuinfo_x86 *c)
-{
-	unsigned int bits;
-
-	bits = c->x86_coreid_bits;
-	/* Low order bits define the core id (index of core in socket) */
-	c->topo.core_id = c->topo.initial_apicid & ((1 << bits)-1);
-	/* Convert the initial APIC ID into the socket ID */
-	c->topo.pkg_id = c->topo.initial_apicid >> bits;
-	/* Use package ID also for last level cache */
-	c->topo.llc_id = c->topo.die_id = c->topo.pkg_id;
-}
 
 static void srat_detect_node(struct cpuinfo_x86 *c)
 {
···
 #endif
 }
 
-static void early_init_hygon_mc(struct cpuinfo_x86 *c)
-{
-#ifdef CONFIG_SMP
-	unsigned int bits, ecx;
-
-	/* Multi core CPU? */
-	if (c->extended_cpuid_level < 0x80000008)
-		return;
-
-	ecx = cpuid_ecx(0x80000008);
-
-	c->x86_max_cores = (ecx & 0xff) + 1;
-
-	/* CPU telling us the core id bits shift? */
-	bits = (ecx >> 12) & 0xF;
-
-	/* Otherwise recompute */
-	if (bits == 0) {
-		while ((1 << bits) < c->x86_max_cores)
-			bits++;
-	}
-
-	c->x86_coreid_bits = bits;
-#endif
-}
-
 static void bsp_init_hygon(struct cpuinfo_x86 *c)
 {
 	if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
···
 
 	if (cpu_has(c, X86_FEATURE_MWAITX))
 		use_mwaitx_delay();
-
-	if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
-		u32 ecx;
-
-		ecx = cpuid_ecx(0x8000001e);
-		__max_die_per_package = nodes_per_socket = ((ecx >> 8) & 7) + 1;
-	} else if (boot_cpu_has(X86_FEATURE_NODEID_MSR)) {
-		u64 value;
-
-		rdmsrl(MSR_FAM10H_NODE_ID, value);
-		__max_die_per_package = nodes_per_socket = ((value >> 3) & 7) + 1;
-	}
 
 	if (!boot_cpu_has(X86_FEATURE_AMD_SSBD) &&
 	    !boot_cpu_has(X86_FEATURE_VIRT_SSBD)) {
···
 static void early_init_hygon(struct cpuinfo_x86 *c)
 {
 	u32 dummy;
-
-	early_init_hygon_mc(c);
 
 	set_cpu_cap(c, X86_FEATURE_K8);
 
···
 	 * we can set it unconditionally.
 	 */
 	set_cpu_cap(c, X86_FEATURE_VMMCALL);
-
-	hygon_get_topology_early(c);
 }
 
 static void init_hygon(struct cpuinfo_x86 *c)
···
 
 	set_cpu_cap(c, X86_FEATURE_REP_GOOD);
 
-	/* get apicid instead of initial apic id from cpuid */
-	c->topo.apicid = read_apic_id();
-
 	/*
 	 * XXX someone from Hygon needs to confirm this DTRT
 	 *
···
 
 	cpu_detect_cache_sizes(c);
 
-	hygon_detect_cmp(c);
-	hygon_get_topology(c);
 	srat_detect_node(c);
 
 	init_hygon_cacheinfo(c);

arch/x86/kernel/cpu/intel.c

···
 	check_memory_type_self_snoop_errata(c);
 
 	/*
-	 * Get the number of SMT siblings early from the extended topology
-	 * leaf, if available. Otherwise try the legacy SMT detection.
-	 */
-	if (detect_extended_topology_early(c) < 0)
-		detect_ht_early(c);
-
-	/*
 	 * Adjust the number of physical bits early because it affects the
 	 * valid bits of the MTRR mask registers.
 	 */
···
 	early_init_intel(c);
 
 	intel_workarounds(c);
-
-	/*
-	 * Detect the extended topology information if available. This
-	 * will reinitialise the initial_apicid which will be used
-	 * in init_intel_cacheinfo()
-	 */
-	detect_extended_topology(c);
-
-	if (!cpu_has(c, X86_FEATURE_XTOPOLOGY)) {
-		/*
-		 * let's use the legacy cpuid vector 0x1 and 0x4 for topology
-		 * detection.
-		 */
-		detect_num_cpu_cores(c);
-#ifdef CONFIG_X86_32
-		detect_ht(c);
-#endif
-	}
 
 	init_intel_cacheinfo(c);
 

arch/x86/kernel/cpu/mce/amd.c

···
 		return -ENODEV;
 
 	if (is_shared_bank(bank)) {
-		nb = node_to_amd_nb(topology_die_id(cpu));
+		nb = node_to_amd_nb(topology_amd_node_id(cpu));
 
 		/* threshold descriptor already initialized on this node? */
 		if (nb && nb->bank4) {
···
 		 * The last CPU on this node using the shared bank is going
 		 * away, remove that bank now.
 		 */
-		nb = node_to_amd_nb(topology_die_id(smp_processor_id()));
+		nb = node_to_amd_nb(topology_amd_node_id(smp_processor_id()));
 		nb->bank4 = NULL;
 	}
 

arch/x86/kernel/cpu/mce/inject.c

···
 
 static u32 get_nbc_for_node(int node_id)
 {
-	struct cpuinfo_x86 *c = &boot_cpu_data;
 	u32 cores_per_node;
 
-	cores_per_node = (c->x86_max_cores * smp_num_siblings) / amd_get_nodes_per_socket();
-
+	cores_per_node = topology_num_threads_per_package() / topology_amd_nodes_per_pkg();
 	return cores_per_node * node_id;
 }
 
···
 	if (boot_cpu_has(X86_FEATURE_AMD_DCM) &&
 	    b == 4 &&
 	    boot_cpu_data.x86 < 0x17) {
-		toggle_nb_mca_mst_cpu(topology_die_id(cpu));
-		cpu = get_nbc_for_node(topology_die_id(cpu));
+		toggle_nb_mca_mst_cpu(topology_amd_node_id(cpu));
+		cpu = get_nbc_for_node(topology_amd_node_id(cpu));
 	}
 
 	cpus_read_lock();

arch/x86/kernel/cpu/microcode/intel.c

···
 {
 	u64 llc_size = c->x86_cache_size * 1024ULL;
 
-	do_div(llc_size, c->x86_max_cores);
+	do_div(llc_size, topology_num_cores_per_package());
 	llc_size_per_core = (unsigned int)llc_size;
 }
 

arch/x86/kernel/cpu/topology.c

···
-// SPDX-License-Identifier: GPL-2.0
+// SPDX-License-Identifier: GPL-2.0-only
 /*
- * Check for extended topology enumeration cpuid leaf 0xb and if it
- * exists, use it for populating initial_apicid and cpu topology
- * detection.
+ * CPU/APIC topology
+ *
+ * The APIC IDs describe the system topology in multiple domain levels.
+ * The CPUID topology parser provides the information which part of the
+ * APIC ID is associated to the individual levels:
+ *
+ * [PACKAGE][DIEGRP][DIE][TILE][MODULE][CORE][THREAD]
+ *
+ * The root space contains the package (socket) IDs.
+ *
+ * Not enumerated levels consume 0 bits space, but conceptually they are
+ * always represented. If e.g. only CORE and THREAD levels are enumerated
+ * then the DIE, MODULE and TILE have the same physical ID as the PACKAGE.
+ *
+ * If SMT is not supported, then the THREAD domain is still used. It then
+ * has the same physical ID as the CORE domain and is the only child of
+ * the core domain.
+ *
+ * This allows a unified view on the system independent of the enumerated
+ * domain levels without requiring any conditionals in the code.
  */
-
+#define pr_fmt(fmt) "CPU topo: " fmt
 #include <linux/cpu.h>
+
+#include <xen/xen.h>
+
 #include <asm/apic.h>
-#include <asm/memtype.h>
-#include <asm/processor.h>
+#include <asm/hypervisor.h>
+#include <asm/io_apic.h>
+#include <asm/mpspec.h>
+#include <asm/smp.h>
 
 #include "cpu.h"
 
-/* leaf 0xb SMT level */
-#define SMT_LEVEL	0
+/*
+ * Map cpu index to physical APIC ID
+ */
+DEFINE_EARLY_PER_CPU_READ_MOSTLY(u32, x86_cpu_to_apicid, BAD_APICID);
+DEFINE_EARLY_PER_CPU_READ_MOSTLY(u32, x86_cpu_to_acpiid, CPU_ACPIID_INVALID);
+EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_apicid);
+EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_acpiid);
 
-/* extended topology sub-leaf types */
-#define INVALID_TYPE	0
-#define SMT_TYPE	1
-#define CORE_TYPE	2
-#define DIE_TYPE	5
+/* Bitmap of physically present CPUs. */
+DECLARE_BITMAP(phys_cpu_present_map, MAX_LOCAL_APIC) __read_mostly;
 
-#define LEAFB_SUBTYPE(ecx)		(((ecx) >> 8) & 0xff)
-#define BITS_SHIFT_NEXT_LEVEL(eax)	((eax) & 0x1f)
-#define LEVEL_MAX_SIBLINGS(ebx)		((ebx) & 0xffff)
+/* Used for CPU number allocation and parallel CPU bringup */
+u32 cpuid_to_apicid[] __ro_after_init = { [0 ... NR_CPUS - 1] = BAD_APICID, };
 
-unsigned int __max_die_per_package __read_mostly = 1;
-EXPORT_SYMBOL(__max_die_per_package);
+/* Bitmaps to mark registered APICs at each topology domain */
+static struct { DECLARE_BITMAP(map, MAX_LOCAL_APIC); } apic_maps[TOPO_MAX_DOMAIN] __ro_after_init;
+
+/*
+ * Keep track of assigned, disabled and rejected CPUs. Present assigned
+ * with 1 as CPU #0 is reserved for the boot CPU.
+ */
+static struct {
+	unsigned int		nr_assigned_cpus;
+	unsigned int		nr_disabled_cpus;
+	unsigned int		nr_rejected_cpus;
+	u32			boot_cpu_apic_id;
+	u32			real_bsp_apic_id;
+} topo_info __ro_after_init = {
+	.nr_assigned_cpus	= 1,
+	.boot_cpu_apic_id	= BAD_APICID,
+	.real_bsp_apic_id	= BAD_APICID,
+};
+
+#define domain_weight(_dom)	bitmap_weight(apic_maps[_dom].map, MAX_LOCAL_APIC)
+
+bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
+{
+	return phys_id == (u64)cpuid_to_apicid[cpu];
+}
 
 #ifdef CONFIG_SMP
-/*
- * Check if given CPUID extended topology "leaf" is implemented
- */
-static int check_extended_topology_leaf(int leaf)
+static void cpu_mark_primary_thread(unsigned int cpu, unsigned int apicid)
 {
-	unsigned int eax, ebx, ecx, edx;
-
-	cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
-
-	if (ebx == 0 || (LEAFB_SUBTYPE(ecx) != SMT_TYPE))
-		return -1;
-
-	return 0;
+	if (!(apicid & (__max_threads_per_core - 1)))
+		cpumask_set_cpu(cpu, &__cpu_primary_thread_mask);
 }
-/*
- * Return best CPUID Extended Topology Leaf supported
- */
-static int detect_extended_topology_leaf(struct cpuinfo_x86 *c)
-{
-	if (c->cpuid_level >= 0x1f) {
-		if (check_extended_topology_leaf(0x1f) == 0)
-			return 0x1f;
-	}
-
-	if (c->cpuid_level >= 0xb) {
-		if (check_extended_topology_leaf(0xb) == 0)
-			return 0xb;
-	}
-
-	return -1;
-}
+#else
+static inline void cpu_mark_primary_thread(unsigned int cpu, unsigned int apicid) { }
 #endif
 
-int detect_extended_topology_early(struct cpuinfo_x86 *c)
+/*
+ * Convert the APIC ID to a domain level ID by masking out the low bits
+ * below the domain level @dom.
+ */
+static inline u32 topo_apicid(u32 apicid, enum x86_topology_domains dom)
 {
-#ifdef CONFIG_SMP
-	unsigned int eax, ebx, ecx, edx;
-	int leaf;
-
-	leaf = detect_extended_topology_leaf(c);
-	if (leaf < 0)
-		return -1;
-
-	set_cpu_cap(c, X86_FEATURE_XTOPOLOGY);
-
-	cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
-	/*
-	 * initial apic id, which also represents 32-bit extended x2apic id.
-	 */
-	c->topo.initial_apicid = edx;
-	smp_num_siblings = max_t(int, smp_num_siblings, LEVEL_MAX_SIBLINGS(ebx));
-#endif
-	return 0;
+	if (dom == TOPO_SMT_DOMAIN)
+		return apicid;
+	return apicid & (UINT_MAX << x86_topo_system.dom_shifts[dom - 1]);
 }
 
-/*
- * Check for extended topology enumeration cpuid leaf, and if it
- * exists, use it for populating initial_apicid and cpu topology
- * detection.
- */
-int detect_extended_topology(struct cpuinfo_x86 *c)
+static int topo_lookup_cpuid(u32 apic_id)
 {
-#ifdef CONFIG_SMP
-	unsigned int eax, ebx, ecx, edx, sub_index;
-	unsigned int ht_mask_width, core_plus_mask_width, die_plus_mask_width;
-	unsigned int core_select_mask, core_level_siblings;
-	unsigned int die_select_mask, die_level_siblings;
-	unsigned int pkg_mask_width;
-	bool die_level_present = false;
-	int leaf;
+	int i;
 
-	leaf = detect_extended_topology_leaf(c);
-	if (leaf < 0)
-		return -1;
+	/* CPU# to APICID mapping is persistent once it is established */
+	for (i = 0; i < topo_info.nr_assigned_cpus; i++) {
+		if (cpuid_to_apicid[i] == apic_id)
+			return i;
+	}
+	return -ENODEV;
+}
 
+static __init int topo_get_cpunr(u32 apic_id)
+{
+	int cpu = topo_lookup_cpuid(apic_id);
+
+	if (cpu >= 0)
+		return cpu;
+
+	return topo_info.nr_assigned_cpus++;
+}
+
+static void topo_set_cpuids(unsigned int cpu, u32 apic_id, u32 acpi_id)
+{
+#if defined(CONFIG_SMP) || defined(CONFIG_X86_64)
+	early_per_cpu(x86_cpu_to_apicid, cpu) = apic_id;
+	early_per_cpu(x86_cpu_to_acpiid, cpu) = acpi_id;
+#endif
+	set_cpu_possible(cpu, true);
+	set_cpu_present(cpu, true);
+}
+
+static __init bool check_for_real_bsp(u32 apic_id)
+{
 	/*
-	 * Populate HT related information from sub-leaf level 0.
+	 * There is no real good way to detect whether this a kdump()
+	 * kernel, but except on the Voyager SMP monstrosity which is not
+	 * longer supported, the real BSP APIC ID is the first one which is
+	 * enumerated by firmware. That allows to detect whether the boot
+	 * CPU is the real BSP. If it is not, then do not register the APIC
+	 * because sending INIT to the real BSP would reset the whole
+	 * system.
+	 *
+	 * The first APIC ID which is enumerated by firmware is detectable
+	 * because the boot CPU APIC ID is registered before that without
+	 * invoking this code.
 	 */
-	cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
-	c->topo.initial_apicid = edx;
-	core_level_siblings = LEVEL_MAX_SIBLINGS(ebx);
-	smp_num_siblings = max_t(int, smp_num_siblings, LEVEL_MAX_SIBLINGS(ebx));
-	core_plus_mask_width = ht_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
-	die_level_siblings = LEVEL_MAX_SIBLINGS(ebx);
-	pkg_mask_width = die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
+	if (topo_info.real_bsp_apic_id != BAD_APICID)
+		return false;
 
-	sub_index = 1;
-	while (true) {
-		cpuid_count(leaf, sub_index, &eax, &ebx, &ecx, &edx);
+	if (apic_id == topo_info.boot_cpu_apic_id) {
+		topo_info.real_bsp_apic_id = apic_id;
+		return false;
+	}
+
+	pr_warn("Boot CPU APIC ID not the first enumerated APIC ID: %x > %x\n",
+		topo_info.boot_cpu_apic_id, apic_id);
+	pr_warn("Crash kernel detected. Disabling real BSP to prevent machine INIT\n");
+
+	topo_info.real_bsp_apic_id = apic_id;
+	return true;
+}
+
+static unsigned int topo_unit_count(u32 lvlid, enum x86_topology_domains at_level,
+				    unsigned long *map)
+{
+	unsigned int id, end, cnt = 0;
+
+	/* Calculate the exclusive end */
+	end = lvlid + (1U << x86_topo_system.dom_shifts[at_level]);
+
+	/* Unfortunately there is no bitmap_weight_range() */
+	for (id = find_next_bit(map, end, lvlid); id < end; id = find_next_bit(map, end, ++id))
+		cnt++;
+	return cnt;
+}
+
+static __init void topo_register_apic(u32 apic_id, u32 acpi_id, bool present)
+{
+	int cpu, dom;
+
+	if (present) {
+		set_bit(apic_id, phys_cpu_present_map);
 
 		/*
-		 * Check for the Core type in the implemented sub leaves.
+		 * Double registration is valid in case of the boot CPU
+		 * APIC because that is registered before the enumeration
+		 * of the APICs via firmware parsers or VM guest
+		 * mechanisms.
 		 */
-		if (LEAFB_SUBTYPE(ecx) == CORE_TYPE) {
-			core_level_siblings = LEVEL_MAX_SIBLINGS(ebx);
-			core_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
-			die_level_siblings = core_level_siblings;
-			die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
-		}
-		if (LEAFB_SUBTYPE(ecx) == DIE_TYPE) {
-			die_level_present = true;
-			die_level_siblings = LEVEL_MAX_SIBLINGS(ebx);
-			die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
-		}
-
-		if (LEAFB_SUBTYPE(ecx) != INVALID_TYPE)
-			pkg_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
+		if (apic_id == topo_info.boot_cpu_apic_id)
+			cpu = 0;
 		else
-			break;
+			cpu = topo_get_cpunr(apic_id);
 
-		sub_index++;
+		cpuid_to_apicid[cpu] = apic_id;
+		topo_set_cpuids(cpu, apic_id, acpi_id);
+	} else {
+		u32 pkgid = topo_apicid(apic_id, TOPO_PKG_DOMAIN);
+
+		/*
+		 * Check for present APICs in the same package when running
+		 * on bare metal. Allow the bogosity in a guest.
+		 */
+		if (hypervisor_is_type(X86_HYPER_NATIVE) &&
+		    topo_unit_count(pkgid, TOPO_PKG_DOMAIN, phys_cpu_present_map)) {
+			pr_info_once("Ignoring hot-pluggable APIC ID %x in present package.\n",
+				     apic_id);
+			topo_info.nr_rejected_cpus++;
+			return;
+		}
+
+		topo_info.nr_disabled_cpus++;
 	}
 
-	core_select_mask = (~(-1 << pkg_mask_width)) >> ht_mask_width;
-	die_select_mask = (~(-1 << die_plus_mask_width)) >>
-				core_plus_mask_width;
+	/* Register present and possible CPUs in the domain maps */
+	for (dom = TOPO_SMT_DOMAIN; dom < TOPO_MAX_DOMAIN; dom++)
+		set_bit(topo_apicid(apic_id, dom), apic_maps[dom].map);
+}
 
-	c->topo.core_id = apic->phys_pkg_id(c->topo.initial_apicid,
-				ht_mask_width) & core_select_mask;
-
-	if (die_level_present) {
-		c->topo.die_id = apic->phys_pkg_id(c->topo.initial_apicid,
-					core_plus_mask_width) & die_select_mask;
+/**
+ * topology_register_apic - Register an APIC in early topology maps
+ * @apic_id:	The APIC ID to set up
+ * @acpi_id:	The ACPI ID associated to the APIC
+ * @present:	True if the corresponding CPU is present
+ */
+void __init topology_register_apic(u32 apic_id, u32 acpi_id, bool present)
+{
+	if (apic_id >= MAX_LOCAL_APIC) {
+		pr_err_once("APIC ID %x exceeds kernel limit of: %x\n", apic_id, MAX_LOCAL_APIC - 1);
+		topo_info.nr_rejected_cpus++;
+		return;
 	}
 
-	c->topo.pkg_id = apic->phys_pkg_id(c->topo.initial_apicid, pkg_mask_width);
-	/*
-	 * Reinit the apicid, now that we have extended initial_apicid.
-	 */
-	c->topo.apicid = apic->phys_pkg_id(c->topo.initial_apicid, 0);
+	if (check_for_real_bsp(apic_id)) {
+		topo_info.nr_rejected_cpus++;
+		return;
+	}
 
-	c->x86_max_cores = (core_level_siblings / smp_num_siblings);
-	__max_die_per_package = (die_level_siblings / core_level_siblings);
+	/* CPU numbers exhausted? */
+	if (apic_id != topo_info.boot_cpu_apic_id && topo_info.nr_assigned_cpus >= nr_cpu_ids) {
+		pr_warn_once("CPU limit of %d reached. Ignoring further CPUs\n", nr_cpu_ids);
+		topo_info.nr_rejected_cpus++;
+		return;
+	}
+
+	topo_register_apic(apic_id, acpi_id, present);
+}
+
+/**
+ * topology_register_boot_apic - Register the boot CPU APIC
+ * @apic_id:	The APIC ID to set up
+ *
+ * Separate so CPU #0 can be assigned
+ */
+void __init topology_register_boot_apic(u32 apic_id)
+{
+	WARN_ON_ONCE(topo_info.boot_cpu_apic_id != BAD_APICID);
+
+	topo_info.boot_cpu_apic_id = apic_id;
+	topo_register_apic(apic_id, CPU_ACPIID_INVALID, true);
+}
+
+/**
+ * topology_get_logical_id - Retrieve the logical ID at a given topology domain level
+ * @apicid:		The APIC ID for which to lookup the logical ID
+ * @at_level:		The topology domain level to use
+ *
+ * @apicid must be a full APIC ID, not the normalized variant. It's valid to have
+ * all bits below the domain level specified by @at_level to be clear. So both
+ * real APIC IDs and backshifted normalized APIC IDs work correctly.
+ *
+ * Returns:
+ *  - >= 0:	The requested logical ID
+ *  - -ERANGE:	@apicid is out of range
+ *  - -ENODEV:	@apicid is not registered
+ */
+int topology_get_logical_id(u32 apicid, enum x86_topology_domains at_level)
+{
+	/* Remove the bits below @at_level to get the proper level ID of @apicid */
+	unsigned int lvlid = topo_apicid(apicid, at_level);
+
+	if (lvlid >= MAX_LOCAL_APIC)
+		return -ERANGE;
+	if (!test_bit(lvlid, apic_maps[at_level].map))
+		return -ENODEV;
+	/* Get the number of set bits before @lvlid. */
+	return bitmap_weight(apic_maps[at_level].map, lvlid);
+}
+EXPORT_SYMBOL_GPL(topology_get_logical_id);
+
+/**
+ * topology_unit_count - Retrieve the count of specified units at a given topology domain level
+ * @apicid:		The APIC ID which specifies the search range
+ * @which_units:	The domain level specifying the units to count
+ * @at_level:		The domain level at which @which_units have to be counted
+ *
+ * This returns the number of possible units according to the enumerated
+ * information.
+ *
+ * E.g. topology_count_units(apicid, TOPO_CORE_DOMAIN, TOPO_PKG_DOMAIN)
+ * counts the number of possible cores in the package to which @apicid
+ * belongs.
+ *
+ * @at_level must obviously be greater than @which_level to produce useful
+ * results.  If @at_level is equal to @which_units the result is
+ * unsurprisingly 1. If @at_level is less than @which_units the results
+ * is by definition undefined and the function returns 0.
+ */
+unsigned int topology_unit_count(u32 apicid, enum x86_topology_domains which_units,
+				 enum x86_topology_domains at_level)
+{
+	/* Remove the bits below @at_level to get the proper level ID of @apicid */
+	unsigned int lvlid = topo_apicid(apicid, at_level);
+
+	if (lvlid >= MAX_LOCAL_APIC)
+		return 0;
+	if (!test_bit(lvlid, apic_maps[at_level].map))
+		return 0;
+	if (which_units > at_level)
+		return 0;
+	if (which_units == at_level)
+		return 1;
+	return topo_unit_count(lvlid, at_level, apic_maps[which_units].map);
+}
+
+#ifdef CONFIG_ACPI_HOTPLUG_CPU
+/**
+ * topology_hotplug_apic - Handle a physical hotplugged APIC after boot
+ * @apic_id:	The APIC ID to set up
+ * @acpi_id:	The ACPI ID associated to the APIC
+ */
+int topology_hotplug_apic(u32 apic_id, u32 acpi_id)
+{
+	int cpu;
+
+	if (apic_id >= MAX_LOCAL_APIC)
+		return -EINVAL;
+
+	/* Reject if the APIC ID was not registered during enumeration. */
+	if (!test_bit(apic_id, apic_maps[TOPO_SMT_DOMAIN].map))
+		return -ENODEV;
+
+	cpu = topo_lookup_cpuid(apic_id);
+	if (cpu < 0)
+		return -ENOSPC;
+
+	set_bit(apic_id, phys_cpu_present_map);
+	topo_set_cpuids(cpu, apic_id, acpi_id);
+	cpu_mark_primary_thread(cpu, apic_id);
+	return cpu;
+}
+
+/**
+ * topology_hotunplug_apic - Remove a physical hotplugged APIC after boot
+ * @cpu:	The CPU number for which the APIC ID is removed
+ */
+void topology_hotunplug_apic(unsigned int cpu)
+{
+	u32 apic_id = cpuid_to_apicid[cpu];
+
+	if (apic_id == BAD_APICID)
+		return;
+
+	per_cpu(x86_cpu_to_apicid, cpu) = BAD_APICID;
+	clear_bit(apic_id, phys_cpu_present_map);
+	set_cpu_present(cpu, false);
+}
 #endif
+
+#ifdef CONFIG_X86_LOCAL_APIC
+static unsigned int max_possible_cpus __initdata = NR_CPUS;
+
+/**
+ * topology_apply_cmdline_limits_early - Apply topology command line limits early
+ *
+ * Ensure that command line limits are in effect before firmware parsing
+ * takes place.
+ */
+void __init topology_apply_cmdline_limits_early(void)
+{
+	unsigned int possible = nr_cpu_ids;
+
+	/* 'maxcpus=0' 'nosmp' 'nolapic' 'disableapic' 'noapic' */
+	if (!setup_max_cpus || ioapic_is_disabled || apic_is_disabled)
+		possible = 1;
+
+	/* 'possible_cpus=N' */
+	possible = min_t(unsigned int, max_possible_cpus, possible);
+
+	if (possible < nr_cpu_ids) {
+		pr_info("Limiting to %u possible CPUs\n", possible);
+		set_nr_cpu_ids(possible);
+	}
+}
+
+static __init bool restrict_to_up(void)
+{
+	if (!smp_found_config || ioapic_is_disabled)
+		return true;
+	/*
+	 * XEN PV is special as it does not advertise the local APIC
+	 * properly, but provides a fake topology for it so that the
+	 * infrastructure works. So don't apply the restrictions vs. APIC
+	 * here.
+	 */
+	if (xen_pv_domain())
+		return false;
+
+	return apic_is_disabled;
+}
+
+void __init topology_init_possible_cpus(void)
+{
+	unsigned int assigned = topo_info.nr_assigned_cpus;
+	unsigned int disabled = topo_info.nr_disabled_cpus;
+	unsigned int cnta, cntb, cpu, allowed = 1;
+	unsigned int total = assigned + disabled;
+	u32 apicid, firstid;
+
+	if (!restrict_to_up()) {
+		if (WARN_ON_ONCE(assigned > nr_cpu_ids)) {
+			disabled += assigned - nr_cpu_ids;
+			assigned = nr_cpu_ids;
+		}
+		allowed = min_t(unsigned int, total, nr_cpu_ids);
+	}
+
+	if (total > allowed)
+		pr_warn("%u possible CPUs exceed the limit of %u\n", total, allowed);
+
+	assigned = min_t(unsigned int, allowed, assigned);
+	disabled = allowed - assigned;
+
+	topo_info.nr_assigned_cpus = assigned;
+	topo_info.nr_disabled_cpus = disabled;
+
+	total_cpus = allowed;
+	set_nr_cpu_ids(allowed);
+
+	cnta = domain_weight(TOPO_PKG_DOMAIN);
+	cntb = domain_weight(TOPO_DIE_DOMAIN);
+	__max_logical_packages = cnta;
+	__max_dies_per_package = 1U << (get_count_order(cntb) - get_count_order(cnta));
+
+	pr_info("Max. logical packages: %3u\n", cnta);
+	pr_info("Max. logical dies:     %3u\n", cntb);
+	pr_info("Max. dies per package: %3u\n", __max_dies_per_package);
+
+	cnta = domain_weight(TOPO_CORE_DOMAIN);
+	cntb = domain_weight(TOPO_SMT_DOMAIN);
+	/*
+	 * Can't use order delta here as order(cnta) can be equal
+	 * order(cntb) even if cnta != cntb.
+	 */
+	__max_threads_per_core = DIV_ROUND_UP(cntb, cnta);
+	pr_info("Max. threads per core: %3u\n", __max_threads_per_core);
+
+	firstid = find_first_bit(apic_maps[TOPO_SMT_DOMAIN].map, MAX_LOCAL_APIC);
+	__num_cores_per_package = topology_unit_count(firstid, TOPO_CORE_DOMAIN, TOPO_PKG_DOMAIN);
+	pr_info("Num. cores per package:   %3u\n", __num_cores_per_package);
+	__num_threads_per_package = topology_unit_count(firstid, TOPO_SMT_DOMAIN, TOPO_PKG_DOMAIN);
+	pr_info("Num. threads per package: %3u\n", __num_threads_per_package);
+
+	pr_info("Allowing %u present CPUs plus %u hotplug CPUs\n", assigned, disabled);
+	if (topo_info.nr_rejected_cpus)
+		pr_info("Rejected CPUs %u\n", topo_info.nr_rejected_cpus);
+
+	init_cpu_present(cpumask_of(0));
+	init_cpu_possible(cpumask_of(0));
+
+	/* Assign CPU numbers to non-present CPUs */
+	for (apicid = 0; disabled; disabled--, apicid++) {
+		apicid = find_next_andnot_bit(apic_maps[TOPO_SMT_DOMAIN].map, phys_cpu_present_map,
+					      MAX_LOCAL_APIC, apicid);
+		if (apicid >= MAX_LOCAL_APIC)
+			break;
+		cpuid_to_apicid[topo_info.nr_assigned_cpus++] = apicid;
+	}
+
+	for (cpu = 0; cpu < allowed; cpu++) {
+		apicid = cpuid_to_apicid[cpu];
+
+		set_cpu_possible(cpu, true);
+
+		if (apicid == BAD_APICID)
+			continue;
+
+		cpu_mark_primary_thread(cpu, apicid);
+		set_cpu_present(cpu, test_bit(apicid, phys_cpu_present_map));
+	}
+}
+
+/*
+ * Late SMP disable after sizing CPU masks when APIC/IOAPIC setup failed.
+ */
+void __init topology_reset_possible_cpus_up(void)
+{
+	init_cpu_present(cpumask_of(0));
+	init_cpu_possible(cpumask_of(0));
+
+	bitmap_zero(phys_cpu_present_map, MAX_LOCAL_APIC);
+	if (topo_info.boot_cpu_apic_id != BAD_APICID)
+		set_bit(topo_info.boot_cpu_apic_id, phys_cpu_present_map);
+}
+
+static int __init setup_possible_cpus(char *str)
+{
+	get_option(&str, &max_possible_cpus);
 	return 0;
 }
+early_param("possible_cpus", setup_possible_cpus);
+#endif

arch/x86/kernel/cpu/topology.h

···
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef ARCH_X86_TOPOLOGY_H
+#define ARCH_X86_TOPOLOGY_H
+
+struct topo_scan {
+	struct cpuinfo_x86	*c;
+	unsigned int		dom_shifts[TOPO_MAX_DOMAIN];
+	unsigned int		dom_ncpus[TOPO_MAX_DOMAIN];
+
+	/* Legacy CPUID[1]:EBX[23:16] number of logical processors */
+	unsigned int		ebx1_nproc_shift;
+
+	/* AMD specific node ID which cannot be mapped into APIC space. */
+	u16			amd_nodes_per_pkg;
+	u16			amd_node_id;
+};
+
+void cpu_init_topology(struct cpuinfo_x86 *c);
+void cpu_parse_topology(struct cpuinfo_x86 *c);
+void topology_set_dom(struct topo_scan *tscan, enum x86_topology_domains dom,
+		      unsigned int shift, unsigned int ncpus);
+bool cpu_parse_topology_ext(struct topo_scan *tscan);
+void cpu_parse_topology_amd(struct topo_scan *tscan);
+void cpu_topology_fixup_amd(struct topo_scan *tscan);
+
+static inline u32 topo_shift_apicid(u32 apicid, enum x86_topology_domains dom)
+{
+	if (dom == TOPO_SMT_DOMAIN)
+		return apicid;
+	return apicid >> x86_topo_system.dom_shifts[dom - 1];
+}
+
+static inline u32 topo_relative_domain_id(u32 apicid, enum x86_topology_domains dom)
+{
+	if (dom != TOPO_SMT_DOMAIN)
+		apicid >>= x86_topo_system.dom_shifts[dom - 1];
+	return apicid & (x86_topo_system.dom_size[dom] - 1);
+}
+
+static inline u32 topo_domain_mask(enum x86_topology_domains dom)
+{
+	return (1U << x86_topo_system.dom_shifts[dom]) - 1;
+}
+
+/*
+ * Update a domain level after the fact without propagating. Used to fixup
+ * broken CPUID enumerations.
+ */
+static inline void topology_update_dom(struct topo_scan *tscan, enum x86_topology_domains dom,
+				       unsigned int shift, unsigned int ncpus)
+{
+	tscan->dom_shifts[dom] = shift;
+	tscan->dom_ncpus[dom] = ncpus;
+}
+
+#ifdef CONFIG_X86_LOCAL_APIC
+unsigned int topology_unit_count(u32 apicid, enum x86_topology_domains which_units,
+				 enum x86_topology_domains at_level);
+#else
+static inline unsigned int topology_unit_count(u32 apicid, enum x86_topology_domains which_units,
+					       enum x86_topology_domains at_level)
+{
+	return 1;
+}
+#endif
+
+#endif /* ARCH_X86_TOPOLOGY_H */

arch/x86/kernel/cpu/topology_amd.c

···
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/cpu.h>
+
+#include <asm/apic.h>
+#include <asm/memtype.h>
+#include <asm/processor.h>
+
+#include "cpu.h"
+
+static bool parse_8000_0008(struct topo_scan *tscan)
+{
+	struct {
+		// ecx
+		u32	cpu_nthreads		:  8, // Number of physical threads - 1
+						:  4, // Reserved
+			apicid_coreid_len	:  4, // Number of thread core ID bits (shift) in APIC ID
+			perf_tsc_len		:  2, // Performance time-stamp counter size
+						: 14; // Reserved
+	} ecx;
+	unsigned int sft;
+
+	if (tscan->c->extended_cpuid_level < 0x80000008)
+		return false;
+
+	cpuid_leaf_reg(0x80000008, CPUID_ECX, &ecx);
+
+	/* If the thread bits are 0, then get the shift value from ecx.cpu_nthreads */
+	sft = ecx.apicid_coreid_len;
+	if (!sft)
+		sft = get_count_order(ecx.cpu_nthreads + 1);
+
+	topology_set_dom(tscan, TOPO_SMT_DOMAIN, sft, ecx.cpu_nthreads + 1);
+	return true;
+}
+
+static void store_node(struct topo_scan *tscan, unsigned int nr_nodes, u16 node_id)
+{
+	/*
+	 * Starting with Fam 17h the DIE domain could probably be used to
+	 * retrieve the node info on AMD/HYGON. Analysis of CPUID dumps
+	 * suggests it's the topmost bit(s) of the CPU cores area, but
+	 * that's guess work and neither enumerated nor documented.
+	 *
+	 * Up to Fam 16h this does not work at all and the legacy node ID
+	 * has to be used.
+	 */
+	tscan->amd_nodes_per_pkg = nr_nodes;
+	tscan->amd_node_id = node_id;
+}
+
+static bool parse_8000_001e(struct topo_scan *tscan, bool has_0xb)
+{
+	struct {
+		// eax
+		u32	ext_apic_id		: 32; // Extended APIC ID
+		// ebx
+		u32	core_id			:  8, // Unique per-socket logical core unit ID
+			core_nthreads		:  8, // #Threads per core (zero-based)
+						: 16; // Reserved
+		// ecx
+		u32	node_id			:  8, // Node (die) ID of invoking logical CPU
+			nnodes_per_socket	:  3, // #nodes in invoking logical CPU's package/socket
+						: 21; // Reserved
+		// edx
+		u32				: 32; // Reserved
+	} leaf;
+
+	if (!boot_cpu_has(X86_FEATURE_TOPOEXT))
+		return false;
+
+	cpuid_leaf(0x8000001e, &leaf);
+
+	tscan->c->topo.initial_apicid = leaf.ext_apic_id;
+
+	/*
+	 * If leaf 0xb is available, then SMT shift is set already. If not
+	 * take it from ecx.threads_per_core and use topo_update_dom() -
+	 * topology_set_dom() would propagate and overwrite the already
+	 * propagated CORE level.
+	 */
+	if (!has_0xb) {
+		unsigned int nthreads = leaf.core_nthreads + 1;
+
+		topology_update_dom(tscan, TOPO_SMT_DOMAIN, get_count_order(nthreads), nthreads);
+	}
+
+	store_node(tscan, leaf.nnodes_per_socket + 1, leaf.node_id);
+
+	if (tscan->c->x86_vendor == X86_VENDOR_AMD) {
+		if (tscan->c->x86 == 0x15)
+			tscan->c->topo.cu_id = leaf.core_id;
+
+		cacheinfo_amd_init_llc_id(tscan->c, leaf.node_id);
+	} else {
+		/*
+		 * Package ID is ApicId[6..] on certain Hygon CPUs. See
+		 * commit e0ceeae708ce for explanation. The topology info
+		 * is screwed up: The package shift is always 6 and the
+		 * node ID is bit [4:5].
+		 */
+		if (!boot_cpu_has(X86_FEATURE_HYPERVISOR) && tscan->c->x86_model <= 0x3) {
+			topology_set_dom(tscan, TOPO_CORE_DOMAIN, 6,
+					 tscan->dom_ncpus[TOPO_CORE_DOMAIN]);
+		}
+		cacheinfo_hygon_init_llc_id(tscan->c);
+	}
+	return true;
+}
+
+static bool parse_fam10h_node_id(struct topo_scan *tscan)
+{
+	struct {
+		union {
+			u64	node_id		:  3,
+				nodes_per_pkg	:  3,
+				unused		: 58;
+			u64	msr;
+		};
+	} nid;
+
+	if (!boot_cpu_has(X86_FEATURE_NODEID_MSR))
+		return false;
+
+	rdmsrl(MSR_FAM10H_NODE_ID, nid.msr);
+	store_node(tscan, nid.nodes_per_pkg + 1, nid.node_id);
+	tscan->c->topo.llc_id = nid.node_id;
+	return true;
+}
+
+static void legacy_set_llc(struct topo_scan *tscan)
+{
+	unsigned int apicid = tscan->c->topo.initial_apicid;
+
+	/* parse_8000_0008() set everything up except llc_id */
+	tscan->c->topo.llc_id = apicid >> tscan->dom_shifts[TOPO_CORE_DOMAIN];
+}
+
+static void parse_topology_amd(struct topo_scan *tscan)
+{
+	bool has_0xb = false;
+
+	/*
+	 * If the extended topology leaf 0x8000_001e is available
+	 * try to get SMT and CORE shift from leaf 0xb first, then
+	 * try to get the CORE shift from leaf 0x8000_0008.
+	 */
+	if (cpu_feature_enabled(X86_FEATURE_TOPOEXT))
+		has_0xb = cpu_parse_topology_ext(tscan);
+
+	if (!has_0xb && !parse_8000_0008(tscan))
+		return;
+
+	/* Prefer leaf 0x8000001e if available */
+	if (parse_8000_001e(tscan, has_0xb))
+		return;
+
+	/* Try the NODEID MSR */
+	if (parse_fam10h_node_id(tscan))
+		return;
+
+	legacy_set_llc(tscan);
+}
+
+void cpu_parse_topology_amd(struct topo_scan *tscan)
+{
+	tscan->amd_nodes_per_pkg = 1;
+	parse_topology_amd(tscan);
+
+	if (tscan->amd_nodes_per_pkg > 1)
+		set_cpu_cap(tscan->c, X86_FEATURE_AMD_DCM);
+}
+
+void cpu_topology_fixup_amd(struct topo_scan *tscan)
+{
+	struct cpuinfo_x86 *c = tscan->c;
+
+	/*
+	 * Adjust the core_id relative to the node when there is more than
+	 * one node.
+	 */
+	if (tscan->c->x86 < 0x17 && tscan->amd_nodes_per_pkg > 1)
+		c->topo.core_id %= tscan->dom_ncpus[TOPO_CORE_DOMAIN] / tscan->amd_nodes_per_pkg;
+}

arch/x86/kernel/cpu/topology_common.c

···
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/cpu.h>
+
+#include <xen/xen.h>
+
+#include <asm/apic.h>
+#include <asm/processor.h>
+#include <asm/smp.h>
+
+#include "cpu.h"
+
+struct x86_topology_system x86_topo_system __ro_after_init;
+EXPORT_SYMBOL_GPL(x86_topo_system);
+
+unsigned int __amd_nodes_per_pkg __ro_after_init;
+EXPORT_SYMBOL_GPL(__amd_nodes_per_pkg);
+
+void topology_set_dom(struct topo_scan *tscan, enum x86_topology_domains dom,
+		      unsigned int shift, unsigned int ncpus)
+{
+	topology_update_dom(tscan, dom, shift, ncpus);
+
+	/* Propagate to the upper levels */
+	for (dom++; dom < TOPO_MAX_DOMAIN; dom++) {
+		tscan->dom_shifts[dom] = tscan->dom_shifts[dom - 1];
+		tscan->dom_ncpus[dom] = tscan->dom_ncpus[dom - 1];
+	}
+}
+
+static unsigned int __maybe_unused parse_num_cores_legacy(struct cpuinfo_x86 *c)
+{
+	struct {
+		u32	cache_type	:  5,
+			unused		: 21,
+			ncores		:  6;
+	} eax;
+
+	if (c->cpuid_level < 4)
+		return 1;
+
+	cpuid_subleaf_reg(4, 0, CPUID_EAX, &eax);
+	if (!eax.cache_type)
+		return 1;
+
+	return eax.ncores + 1;
+}
+
+static void parse_legacy(struct topo_scan *tscan)
+{
+	unsigned int cores, core_shift, smt_shift = 0;
+	struct cpuinfo_x86 *c = tscan->c;
+
+	cores = parse_num_cores_legacy(c);
+	core_shift = get_count_order(cores);
+
+	if (cpu_has(c, X86_FEATURE_HT)) {
+		if (!WARN_ON_ONCE(tscan->ebx1_nproc_shift < core_shift))
+			smt_shift = tscan->ebx1_nproc_shift - core_shift;
+		/*
+		 * The parser expects leaf 0xb/0x1f format, which means
+		 * the number of logical processors at core level is
+		 * counting threads.
+		 */
+		core_shift += smt_shift;
+		cores <<= smt_shift;
+	}
+
+	topology_set_dom(tscan, TOPO_SMT_DOMAIN, smt_shift, 1U << smt_shift);
+	topology_set_dom(tscan, TOPO_CORE_DOMAIN, core_shift, cores);
+}
+
+static bool fake_topology(struct topo_scan *tscan)
+{
+	/*
+	 * Preset the CORE level shift for CPUID less systems and XEN_PV,
+	 * which has useless CPUID information.
+	 */
+	topology_set_dom(tscan, TOPO_SMT_DOMAIN, 0, 1);
+	topology_set_dom(tscan, TOPO_CORE_DOMAIN, 0, 1);
+
+	return tscan->c->cpuid_level < 1;
+}
+
+static void parse_topology(struct topo_scan *tscan, bool early)
+{
+	const struct cpuinfo_topology topo_defaults = {
+		.cu_id			= 0xff,
+		.llc_id			= BAD_APICID,
+		.l2c_id			= BAD_APICID,
+	};
+	struct cpuinfo_x86 *c = tscan->c;
+	struct {
+		u32	unused0		: 16,
+			nproc		:  8,
+			apicid		:  8;
+	} ebx;
+
+	c->topo = topo_defaults;
+
+	if (fake_topology(tscan))
+		return;
+
+	/* Preset Initial APIC ID from CPUID leaf 1 */
+	cpuid_leaf_reg(1, CPUID_EBX, &ebx);
+	c->topo.initial_apicid = ebx.apicid;
+
+	/*
+	 * The initial invocation from early_identify_cpu() happens before
+	 * the APIC is mapped or X2APIC enabled. For establishing the
+	 * topology, that's not required. Use the initial APIC ID.
+	 */
+	if (early)
+		c->topo.apicid = c->topo.initial_apicid;
+	else
+		c->topo.apicid = read_apic_id();
+
+	/* The above is sufficient for UP */
+	if (!IS_ENABLED(CONFIG_SMP))
+		return;
+
+	tscan->ebx1_nproc_shift = get_count_order(ebx.nproc);
+
+	switch (c->x86_vendor) {
+	case X86_VENDOR_AMD:
+		if (IS_ENABLED(CONFIG_CPU_SUP_AMD))
+			cpu_parse_topology_amd(tscan);
+		break;
+	case X86_VENDOR_CENTAUR:
+	case X86_VENDOR_ZHAOXIN:
+		parse_legacy(tscan);
+		break;
+	case X86_VENDOR_INTEL:
+		if (!IS_ENABLED(CONFIG_CPU_SUP_INTEL) || !cpu_parse_topology_ext(tscan))
+			parse_legacy(tscan);
+		break;
+	case X86_VENDOR_HYGON:
+		if (IS_ENABLED(CONFIG_CPU_SUP_HYGON))
+			cpu_parse_topology_amd(tscan);
+		break;
+	}
+}
+
+static void topo_set_ids(struct topo_scan *tscan)
+{
+	struct cpuinfo_x86 *c = tscan->c;
+	u32 apicid = c->topo.apicid;
+
+	c->topo.pkg_id = topo_shift_apicid(apicid, TOPO_PKG_DOMAIN);
+	c->topo.die_id = topo_shift_apicid(apicid, TOPO_DIE_DOMAIN);
+
+	c->topo.logical_pkg_id = topology_get_logical_id(apicid, TOPO_PKG_DOMAIN);
+	c->topo.logical_die_id = topology_get_logical_id(apicid, TOPO_DIE_DOMAIN);
+
+	/* Package relative core ID */
+	c->topo.core_id = (apicid & topo_domain_mask(TOPO_PKG_DOMAIN)) >>
+		x86_topo_system.dom_shifts[TOPO_SMT_DOMAIN];
+
+	c->topo.amd_node_id = tscan->amd_node_id;
+
+	if (c->x86_vendor == X86_VENDOR_AMD)
+		cpu_topology_fixup_amd(tscan);
+}
+
+void cpu_parse_topology(struct cpuinfo_x86 *c)
+{
+	unsigned int dom, cpu = smp_processor_id();
+	struct topo_scan tscan = { .c = c, };
+
+	parse_topology(&tscan, false);
+
+	if (IS_ENABLED(CONFIG_X86_LOCAL_APIC)) {
+		if (c->topo.initial_apicid != c->topo.apicid) {
+			pr_err(FW_BUG "CPU%4u: APIC ID mismatch. CPUID: 0x%04x APIC: 0x%04x\n",
+			       cpu, c->topo.initial_apicid, c->topo.apicid);
+		}
+
+		if (c->topo.apicid != cpuid_to_apicid[cpu]) {
+			pr_err(FW_BUG "CPU%4u: APIC ID mismatch. Firmware: 0x%04x APIC: 0x%04x\n",
+			       cpu, cpuid_to_apicid[cpu], c->topo.apicid);
+		}
+	}
+
+	for (dom = TOPO_SMT_DOMAIN; dom < TOPO_MAX_DOMAIN; dom++) {
+		if (tscan.dom_shifts[dom] == x86_topo_system.dom_shifts[dom])
+			continue;
+		pr_err(FW_BUG "CPU%d: Topology domain %u shift %u != %u\n", cpu, dom,
+		       tscan.dom_shifts[dom], x86_topo_system.dom_shifts[dom]);
+	}
+
+	topo_set_ids(&tscan);
+}
+
+void __init cpu_init_topology(struct cpuinfo_x86 *c)
+{
+	struct topo_scan tscan = { .c = c, };
+	unsigned int dom, sft;
+
+	parse_topology(&tscan, true);
+
+	/* Copy the shift values and calculate the unit sizes. */
+	memcpy(x86_topo_system.dom_shifts, tscan.dom_shifts, sizeof(x86_topo_system.dom_shifts));
+
+	dom = TOPO_SMT_DOMAIN;
+	x86_topo_system.dom_size[dom] = 1U << x86_topo_system.dom_shifts[dom];
+
+	for (dom++; dom < TOPO_MAX_DOMAIN; dom++) {
+		sft = x86_topo_system.dom_shifts[dom] - x86_topo_system.dom_shifts[dom - 1];
+		x86_topo_system.dom_size[dom] = 1U << sft;
+	}
+
+	topo_set_ids(&tscan);
+
+	/*
+	 * AMD systems have Nodes per package which cannot be mapped to
+	 * APIC ID.
+	 */
+	__amd_nodes_per_pkg = tscan.amd_nodes_per_pkg;
+}

arch/x86/kernel/cpu/topology_ext.c

···
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/cpu.h>
+
+#include <asm/apic.h>
+#include <asm/memtype.h>
+#include <asm/processor.h>
+
+#include "cpu.h"
+
+enum topo_types {
+	INVALID_TYPE		= 0,
+	SMT_TYPE		= 1,
+	CORE_TYPE		= 2,
+	MAX_TYPE_0B		= 3,
+	MODULE_TYPE		= 3,
+	TILE_TYPE		= 4,
+	DIE_TYPE		= 5,
+	DIEGRP_TYPE		= 6,
+	MAX_TYPE_1F		= 7,
+};
+
+/*
+ * Use a lookup table for the case that there are future types > 6 which
+ * describe an intermediate domain level which does not exist today.
+ */
+static const unsigned int topo_domain_map_0b_1f[MAX_TYPE_1F] = {
+	[SMT_TYPE]	= TOPO_SMT_DOMAIN,
+	[CORE_TYPE]	= TOPO_CORE_DOMAIN,
+	[MODULE_TYPE]	= TOPO_MODULE_DOMAIN,
+	[TILE_TYPE]	= TOPO_TILE_DOMAIN,
+	[DIE_TYPE]	= TOPO_DIE_DOMAIN,
+	[DIEGRP_TYPE]	= TOPO_DIEGRP_DOMAIN,
+};
+
+static inline bool topo_subleaf(struct topo_scan *tscan, u32 leaf, u32 subleaf,
+				unsigned int *last_dom)
+{
+	unsigned int dom, maxtype;
+	const unsigned int *map;
+	struct {
+		// eax
+		u32	x2apic_shift	:  5, // Number of bits to shift APIC ID right
+					      // for the topology ID at the next level
+					: 27; // Reserved
+		// ebx
+		u32	num_processors	: 16, // Number of processors at current level
+					: 16; // Reserved
+		// ecx
+		u32	level		:  8, // Current topology level. Same as sub leaf number
+			type		:  8, // Level type. If 0, invalid
+					: 16; // Reserved
+		// edx
+		u32	x2apic_id	: 32; // X2APIC ID of the current logical processor
+	} sl;
+
+	switch (leaf) {
+	case 0x0b: maxtype = MAX_TYPE_0B; map = topo_domain_map_0b_1f; break;
+	case 0x1f: maxtype = MAX_TYPE_1F; map = topo_domain_map_0b_1f; break;
+	default: return false;
+	}
+
+	cpuid_subleaf(leaf, subleaf, &sl);
+
+	if (!sl.num_processors || sl.type == INVALID_TYPE)
+		return false;
+
+	if (sl.type >= maxtype) {
+		pr_err_once("Topology: leaf 0x%x:%d Unknown domain type %u\n",
+			    leaf, subleaf, sl.type);
+		/*
+		 * It really would have been too obvious to make the domain
+		 * type space sparse and leave a few reserved types between
+		 * the points which might change instead of following the
+		 * usual "this can be fixed in software" principle.
+		 */
+		dom = *last_dom + 1;
+	} else {
+		dom = map[sl.type];
+		*last_dom = dom;
+	}
+
+	if (!dom) {
+		tscan->c->topo.initial_apicid = sl.x2apic_id;
+	} else if (tscan->c->topo.initial_apicid != sl.x2apic_id) {
+		pr_warn_once(FW_BUG "CPUID leaf 0x%x subleaf %d APIC ID mismatch %x != %x\n",
+			     leaf, subleaf, tscan->c->topo.initial_apicid, sl.x2apic_id);
+	}
+
+	topology_set_dom(tscan, dom, sl.x2apic_shift, sl.num_processors);
+	return true;
+}
+
+static bool parse_topology_leaf(struct topo_scan *tscan, u32 leaf)
+{
+	unsigned int last_dom;
+	u32 subleaf;
+
+	/* Read all available subleafs and populate the levels */
+	for (subleaf = 0, last_dom = 0; topo_subleaf(tscan, leaf, subleaf, &last_dom); subleaf++);
+
+	/* If subleaf 0 failed to parse, give up */
+	if (!subleaf)
+		return false;
+
+	/*
+	 * There are machines in the wild which have shift 0 in the subleaf
+	 * 0, but advertise 2 logical processors at that level. They are
+	 * truly SMT.
+	 */
+	if (!tscan->dom_shifts[TOPO_SMT_DOMAIN] && tscan->dom_ncpus[TOPO_SMT_DOMAIN] > 1) {
+		unsigned int sft = get_count_order(tscan->dom_ncpus[TOPO_SMT_DOMAIN]);
+
+		pr_warn_once(FW_BUG "CPUID leaf 0x%x subleaf 0 has shift level 0 but %u CPUs. Fixing it up.\n",
+			     leaf, tscan->dom_ncpus[TOPO_SMT_DOMAIN]);
+		topology_update_dom(tscan, TOPO_SMT_DOMAIN, sft, tscan->dom_ncpus[TOPO_SMT_DOMAIN]);
+	}
+
+	set_cpu_cap(tscan->c, X86_FEATURE_XTOPOLOGY);
+	return true;
+}
+
+bool cpu_parse_topology_ext(struct topo_scan *tscan)
+{
+	/* Intel: Try leaf 0x1F first. */
+	if (tscan->c->cpuid_level >= 0x1f && parse_topology_leaf(tscan, 0x1f))
+		return true;
+
+	/* Intel/AMD: Fall back to leaf 0xB if available */
+	return tscan->c->cpuid_level >= 0x0b && parse_topology_leaf(tscan, 0x0b);
+}

arch/x86/kernel/cpu/zhaoxin.c

···
 {
 	early_init_zhaoxin(c);
 	init_intel_cacheinfo(c);
-	detect_num_cpu_cores(c);
-#ifdef CONFIG_X86_32
-	detect_ht(c);
-#endif
 
 	if (c->cpuid_level > 9) {
 		unsigned int eax = cpuid_eax(10);

arch/x86/kernel/devicetree.c

···
 			pr_warn("%pOF: missing local APIC ID\n", dn);
 			continue;
 		}
-		generic_processor_info(apic_id);
+		topology_register_apic(apic_id, CPU_ACPIID_INVALID, true);
 	}
 }
 
···
 }
 #endif
 
-void __init x86_dtb_init(void)
+void __init x86_dtb_parse_smp_config(void)
 {
 	if (!of_have_populated_dt())
 		return;

arch/x86/kernel/jailhouse.c

···
 #endif
 }
 
-static void __init jailhouse_get_smp_config(unsigned int early)
+static void __init jailhouse_parse_smp_config(void)
 {
 	struct ioapic_domain_cfg ioapic_cfg = {
 		.type = IOAPIC_DOMAIN_STRICT,
···
 	register_lapic_address(0xfee00000);
 
 	for (cpu = 0; cpu < setup_data.v1.num_cpus; cpu++)
-		generic_processor_info(setup_data.v1.cpu_ids[cpu]);
+		topology_register_apic(setup_data.v1.cpu_ids[cpu], CPU_ACPIID_INVALID, true);
 
 	smp_found_config = 1;
 
···
 	struct setup_data header;
 	void *mapping;
 
-	x86_init.irqs.pre_vector_init	= x86_init_noop;
-	x86_init.timers.timer_init	= jailhouse_timer_init;
-	x86_init.mpparse.get_smp_config	= jailhouse_get_smp_config;
-	x86_init.pci.arch_init		= jailhouse_pci_arch_init;
+	x86_init.irqs.pre_vector_init		= x86_init_noop;
+	x86_init.timers.timer_init		= jailhouse_timer_init;
+	x86_init.mpparse.find_mptable		= x86_init_noop;
+	x86_init.mpparse.early_parse_smp_cfg	= x86_init_noop;
+	x86_init.mpparse.parse_smp_cfg		= jailhouse_parse_smp_config;
+	x86_init.pci.arch_init			= jailhouse_pci_arch_init;
 
-	x86_platform.calibrate_cpu	= jailhouse_get_tsc;
-	x86_platform.calibrate_tsc	= jailhouse_get_tsc;
-	x86_platform.get_wallclock	= jailhouse_get_wallclock;
-	x86_platform.legacy.rtc		= 0;
-	x86_platform.legacy.warm_reset	= 0;
-	x86_platform.legacy.i8042	= X86_LEGACY_I8042_PLATFORM_ABSENT;
+	x86_platform.calibrate_cpu		= jailhouse_get_tsc;
+	x86_platform.calibrate_tsc		= jailhouse_get_tsc;
+	x86_platform.get_wallclock		= jailhouse_get_wallclock;
+	x86_platform.legacy.rtc			= 0;
+	x86_platform.legacy.warm_reset		= 0;
+	x86_platform.legacy.i8042		= X86_LEGACY_I8042_PLATFORM_ABSENT;
 
-	legacy_pic			= &null_legacy_pic;
+	legacy_pic				= &null_legacy_pic;
 
-	machine_ops.emergency_restart	= jailhouse_no_restart;
+	machine_ops.emergency_restart		= jailhouse_no_restart;
 
 	while (pa_data) {
 		mapping = early_memremap(pa_data, sizeof(header));

arch/x86/kernel/mpparse.c

···
  * Checksum an MP configuration block.
  */
 
+static unsigned int num_procs __initdata;
+
 static int __init mpf_checksum(unsigned char *mp, int len)
 {
 	int sum = 0;
···
 {
 	char *bootup_cpu = "";
 
-	if (!(m->cpuflag & CPU_ENABLED)) {
-		disabled_cpus++;
+	topology_register_apic(m->apicid, CPU_ACPIID_INVALID, m->cpuflag & CPU_ENABLED);
+	if (!(m->cpuflag & CPU_ENABLED))
 		return;
-	}
 
 	if (m->cpuflag & CPU_BOOTPROCESSOR)
 		bootup_cpu = " (Bootup-CPU)";
 
 	pr_info("Processor #%d%s\n", m->apicid, bootup_cpu);
-	generic_processor_info(m->apicid);
+	num_procs++;
 }
 
 #ifdef CONFIG_X86_IO_APIC
···
 		}
 	}
 
-	if (!num_processors)
+	if (!num_procs && !acpi_lapic)
 		pr_err("MPTABLE: no processors registered!\n");
-	return num_processors;
+	return num_procs || acpi_lapic;
 }
 
 #ifdef CONFIG_X86_IO_APIC
···
 /*
  * Scan the memory blocks for an SMP configuration block.
  */
-void __init default_get_smp_config(unsigned int early)
+static __init void mpparse_get_smp_config(unsigned int early)
 {
 	struct mpf_intel *mpf;
 
···
 	} else
 		BUG();
 
-	if (!early)
-		pr_info("Processors: %d\n", num_processors);
+	if (!early && !acpi_lapic)
+		pr_info("Processors: %d\n", num_procs);
 	/*
 	 * Only use the first configuration found.
 	 */
 out:
 	early_memunmap(mpf, sizeof(*mpf));
+}
+
+void __init mpparse_parse_early_smp_config(void)
+{
+	mpparse_get_smp_config(true);
+}
+
+void __init mpparse_parse_smp_config(void)
+{
+	mpparse_get_smp_config(false);
 }
 
 static void __init smp_reserve_memory(struct mpf_intel *mpf)
···
 	return ret;
 }
 
-void __init default_find_smp_config(void)
+void __init mpparse_find_mptable(void)
 {
 	unsigned int address;
 

arch/x86/kernel/process.c

···
 void select_idle_routine(const struct cpuinfo_x86 *c)
 {
 #ifdef CONFIG_SMP
-	if (boot_option_idle_override == IDLE_POLL && smp_num_siblings > 1)
+	if (boot_option_idle_override == IDLE_POLL && __max_threads_per_core > 1)
 		pr_warn_once("WARNING: polling idle and HT enabled, performance may degrade\n");
 #endif
 	if (x86_idle_set() || boot_option_idle_override == IDLE_POLL)

arch/x86/kernel/setup.c

···
 	high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
 #endif
 
-	/*
-	 * Find and reserve possible boot-time SMP configuration:
-	 */
-	find_smp_config();
+	/* Find and reserve MPTABLE area */
+	x86_init.mpparse.find_mptable();
 
 	early_alloc_pgt_buf();
 
···
 
 	early_platform_quirks();
 
+	/* Some platforms need the APIC registered for NUMA configuration */
 	early_acpi_boot_init();
+	x86_init.mpparse.early_parse_smp_cfg();
 
 	x86_flattree_get_config();
 
···
 
 	early_quirks();
 
+	topology_apply_cmdline_limits_early();
+
 	/*
-	 * Read APIC and some other early information from ACPI tables.
+	 * Parse SMP configuration. Try ACPI first and then the platform
+	 * specific parser.
 	 */
 	acpi_boot_init();
-	x86_dtb_init();
+	x86_init.mpparse.parse_smp_cfg();
 
-	/*
-	 * get boot-time SMP configuration:
-	 */
-	get_smp_config();
-
-	/*
-	 * Systems w/o ACPI and mptables might not have it mapped the local
-	 * APIC yet, but prefill_possible_map() might need to access it.
-	 */
+	/* Last opportunity to detect and map the local APIC */
 	init_apic_mappings();
 
-	prefill_possible_map();
+	topology_init_possible_cpus();
 
 	init_cpu_to_node();
 	init_gi_nodes();

arch/x86/kernel/smpboot.c

···
  */
 static DEFINE_PER_CPU_ALIGNED(struct mwait_cpu_dead, mwait_cpu_dead);
 
-/* Logical package management. */
-struct logical_maps {
-	u32	phys_pkg_id;
-	u32	phys_die_id;
-	u32	logical_pkg_id;
-	u32	logical_die_id;
-};
-
-/* Temporary workaround until the full topology mechanics is in place */
-static DEFINE_PER_CPU_READ_MOSTLY(struct logical_maps, logical_maps) = {
-	.phys_pkg_id	= U32_MAX,
-	.phys_die_id	= U32_MAX,
-};
-
-unsigned int __max_logical_packages __read_mostly;
-EXPORT_SYMBOL(__max_logical_packages);
-static unsigned int logical_packages __read_mostly;
-static unsigned int logical_die __read_mostly;
-
 /* Maximum number of SMT threads on any online core */
 int __read_mostly __max_smt_threads = 1;
 
···
 	cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
 }
 
-/**
- * topology_phys_to_logical_pkg - Map a physical package id to a logical
- * @phys_pkg:	The physical package id to map
- *
- * Returns logical package id or -1 if not found
- */
-int topology_phys_to_logical_pkg(unsigned int phys_pkg)
-{
-	int cpu;
-
-	for_each_possible_cpu(cpu) {
-		if (per_cpu(logical_maps.phys_pkg_id, cpu) == phys_pkg)
-			return per_cpu(logical_maps.logical_pkg_id, cpu);
-	}
-	return -1;
-}
-EXPORT_SYMBOL(topology_phys_to_logical_pkg);
-
-/**
- * topology_phys_to_logical_die - Map a physical die id to logical
- * @die_id:	The physical die id to map
- * @cur_cpu:	The CPU for which the mapping is done
- *
- * Returns logical die id or -1 if not found
- */
-static int topology_phys_to_logical_die(unsigned int die_id, unsigned int cur_cpu)
-{
-	int cpu, proc_id = cpu_data(cur_cpu).topo.pkg_id;
-
-	for_each_possible_cpu(cpu) {
-		if (per_cpu(logical_maps.phys_pkg_id, cpu) == proc_id &&
-		    per_cpu(logical_maps.phys_die_id, cpu) == die_id)
-			return per_cpu(logical_maps.logical_die_id, cpu);
-	}
-	return -1;
-}
-
-/**
- * topology_update_package_map - Update the physical to logical package map
- * @pkg:	The physical package id as retrieved via CPUID
- * @cpu:	The cpu for which this is updated
- */
-int topology_update_package_map(unsigned int pkg, unsigned int cpu)
-{
-	int new;
-
-	/* Already available somewhere? */
-	new = topology_phys_to_logical_pkg(pkg);
-	if (new >= 0)
-		goto found;
-
-	new = logical_packages++;
-	if (new != pkg) {
-		pr_info("CPU %u Converting physical %u to logical package %u\n",
-			cpu, pkg, new);
-	}
-found:
-	per_cpu(logical_maps.phys_pkg_id, cpu) = pkg;
-	per_cpu(logical_maps.logical_pkg_id, cpu) = new;
-	cpu_data(cpu).topo.logical_pkg_id = new;
-	return 0;
-}
-/**
- * topology_update_die_map - Update the physical to logical die map
- * @die:	The die id as retrieved via CPUID
- * @cpu:	The cpu for which this is updated
- */
-int topology_update_die_map(unsigned int die, unsigned int cpu)
-{
-	int new;
-
-	/* Already available somewhere? */
-	new = topology_phys_to_logical_die(die, cpu);
-	if (new >= 0)
-		goto found;
-
-	new = logical_die++;
-	if (new != die) {
-		pr_info("CPU %u Converting physical %u to logical die %u\n",
-			cpu, die, new);
-	}
-found:
-	per_cpu(logical_maps.phys_die_id, cpu) = die;
-	per_cpu(logical_maps.logical_die_id, cpu) = new;
-	cpu_data(cpu).topo.logical_die_id = new;
-	return 0;
-}
-
 static void __init smp_store_boot_cpu_info(void)
 {
-	int id = 0; /* CPU 0 */
-	struct cpuinfo_x86 *c = &cpu_data(id);
+	struct cpuinfo_x86 *c = &cpu_data(0);
 
 	*c = boot_cpu_data;
-	c->cpu_index = id;
-	topology_update_package_map(c->topo.pkg_id, id);
-	topology_update_die_map(c->topo.die_id, id);
 	c->initialized = true;
 }
 
···
 
 		if (c->topo.pkg_id == o->topo.pkg_id &&
 		    c->topo.die_id == o->topo.die_id &&
+		    c->topo.amd_node_id == o->topo.amd_node_id &&
 		    per_cpu_llc_id(cpu1) == per_cpu_llc_id(cpu2)) {
 			if (c->topo.core_id == o->topo.core_id)
 				return topology_sane(c, o, "smt");
···
 
 static bool match_die(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
 {
-	if (c->topo.pkg_id == o->topo.pkg_id &&
-	    c->topo.die_id == o->topo.die_id)
-		return true;
-	return false;
+	if (c->topo.pkg_id != o->topo.pkg_id || c->topo.die_id != o->topo.die_id)
+		return false;
+
+	if (cpu_feature_enabled(X86_FEATURE_TOPOEXT) && topology_amd_nodes_per_pkg() > 1)
+		return c->topo.amd_node_id == o->topo.amd_node_id;
+
+	return true;
 }
 
 static bool match_l2c(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
···
 
 void set_cpu_sibling_map(int cpu)
 {
-	bool has_smt = smp_num_siblings > 1;
-	bool has_mp = has_smt || boot_cpu_data.x86_max_cores > 1;
+	bool has_smt = __max_threads_per_core > 1;
+	bool has_mp = has_smt || topology_num_cores_per_package() > 1;
 	struct cpuinfo_x86 *c = &cpu_data(cpu);
 	struct cpuinfo_x86 *o;
 	int i, threads;
···
 
 	pr_debug("++++++++++++++++++++=_---CPU UP  %u\n", cpu);
 
-	if (apicid == BAD_APICID || !physid_isset(apicid, phys_cpu_present_map) ||
-	    !apic_id_valid(apicid)) {
-		pr_err("%s: bad cpu %d\n", __func__, cpu);
+	if (apicid == BAD_APICID || !apic_id_valid(apicid)) {
+		pr_err("CPU %u has invalid APIC ID %x. Aborting bringup\n", cpu, apicid);
+		return -EINVAL;
+	}
+
+	if (!test_bit(apicid, phys_cpu_present_map)) {
+		pr_err("CPU %u APIC ID %x is not present. Aborting bringup\n", cpu, apicid);
 		return -EINVAL;
 	}
 
···
 	pr_info("SMP disabled\n");
 
 	disable_ioapic_support();
+	topology_reset_possible_cpus_up();
 
-	init_cpu_present(cpumask_of(0));
-	init_cpu_possible(cpumask_of(0));
-
-	if (smp_found_config)
-		physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
-	else
-		physid_set_mask_of_physid(0, &phys_cpu_present_map);
 	cpumask_set_cpu(0, topology_sibling_cpumask(0));
 	cpumask_set_cpu(0, topology_core_cpumask(0));
 	cpumask_set_cpu(0, topology_die_cpumask(0));
···
 	native_pv_lock_init();
 }
 
-void __init calculate_max_logical_packages(void)
-{
-	int ncpus;
-
-	/*
-	 * Today neither Intel nor AMD support heterogeneous systems so
-	 * extrapolate the boot cpu's data to all packages.
-	 */
-	ncpus = cpu_data(0).booted_cores * topology_max_smt_threads();
-	__max_logical_packages = DIV_ROUND_UP(total_cpus, ncpus);
-	pr_info("Max logical packages: %u\n", __max_logical_packages);
-}
-
 void __init native_smp_cpus_done(unsigned int max_cpus)
 {
 	pr_debug("Boot done\n");
 
-	calculate_max_logical_packages();
 	build_sched_topology();
 	nmi_selftest();
 	impress_friends();
 	cache_aps_init();
-}
-
-static int __initdata setup_possible_cpus = -1;
-static int __init _setup_possible_cpus(char *str)
-{
-	get_option(&str, &setup_possible_cpus);
-	return 0;
-}
-early_param("possible_cpus", _setup_possible_cpus);
-
-
-/*
- * cpu_possible_mask should be static, it cannot change as cpu's
- * are onlined, or offlined. The reason is per-cpu data-structures
- * are allocated by some modules at init time, and don't expect to
- * do this dynamically on cpu arrival/departure.
- * cpu_present_mask on the other hand can change dynamically.
- * In case when cpu_hotplug is not compiled, then we resort to current
- * behaviour, which is cpu_possible == cpu_present.
- * - Ashok Raj
- *
- * Three ways to find out the number of additional hotplug CPUs:
- * - If the BIOS specified disabled CPUs in ACPI/mptables use that.
- * - The user can overwrite it with possible_cpus=NUM
- * - Otherwise don't reserve additional CPUs.
- * We do this because additional CPUs waste a lot of memory.
- * -AK
- */
-__init void prefill_possible_map(void)
-{
-	int i, possible;
-
-	i = setup_max_cpus ?: 1;
-	if (setup_possible_cpus == -1) {
-		possible = num_processors;
-#ifdef CONFIG_HOTPLUG_CPU
-		if (setup_max_cpus)
-			possible += disabled_cpus;
-#else
-		if (possible > i)
-			possible = i;
-#endif
-	} else
-		possible = setup_possible_cpus;
-
-	total_cpus = max_t(int, possible, num_processors + disabled_cpus);
-
-	/* nr_cpu_ids could be reduced via nr_cpus= */
-	if (possible > nr_cpu_ids) {
-		pr_warn("%d Processors exceeds NR_CPUS limit of %u\n",
-			possible, nr_cpu_ids);
-		possible = nr_cpu_ids;
-	}
-
-#ifdef CONFIG_HOTPLUG_CPU
-	if (!setup_max_cpus)
-#endif
-	if (possible > i) {
-		pr_warn("%d Processors exceeds max_cpus limit of %u\n",
-			possible, setup_max_cpus);
-		possible = i;
-	}
-
-	set_nr_cpu_ids(possible);
-
-	pr_info("Allowing %d CPUs, %d hotplug CPUs\n",
-		possible, max_t(int, possible - num_processors, 0));
-
-	reset_cpu_possible_mask();
-
-	for (i = 0; i < possible; i++)
-		set_cpu_possible(i, true);
 }
 
 /* correctly size the local cpu masks */

arch/x86/kernel/vsmp_64.c

···
 #endif
 }
 
-static u32 apicid_phys_pkg_id(u32 initial_apic_id, int index_msb)
-{
-	return read_apic_id() >> index_msb;
-}
-
-static void vsmp_apic_post_init(void)
-{
-	/* need to update phys_pkg_id */
-	apic->phys_pkg_id = apicid_phys_pkg_id;
-}
-
 void __init vsmp_init(void)
 {
 	detect_vsmp_box();
 	if (!is_vsmp_box())
 		return;
-
-	x86_platform.apic_post_init = vsmp_apic_post_init;
 
 	vsmp_cap_cpus();
 

arch/x86/kernel/x86_init.c

···
 
 	.mpparse = {
 		.setup_ioapic_ids	= x86_init_noop,
-		.find_smp_config	= default_find_smp_config,
-		.get_smp_config		= default_get_smp_config,
+		.find_mptable		= mpparse_find_mptable,
+		.early_parse_smp_cfg	= mpparse_parse_early_smp_config,
+		.parse_smp_cfg		= mpparse_parse_smp_config,
 	},
 
 	.irqs = {

arch/x86/mm/amdtopology.c

···
 
 int __init amd_numa_init(void)
 {
-	u64 start = PFN_PHYS(0);
+	unsigned int numnodes, cores, apicid;
+	u64 prevbase, start = PFN_PHYS(0);
 	u64 end = PFN_PHYS(max_pfn);
-	unsigned numnodes;
-	u64 prevbase;
-	int i, j, nb;
 	u32 nodeid, reg;
-	unsigned int bits, cores, apicid_base;
+	int i, j, nb;
 
 	if (!early_pci_allowed())
 		return -EINVAL;
···
 		return -ENOENT;
 
 	/*
-	 * We seem to have valid NUMA configuration.  Map apicids to nodes
-	 * using the coreid bits from early_identify_cpu.
+	 * We seem to have valid NUMA configuration. Map apicids to nodes
+	 * using the size of the core domain in the APIC space.
 	 */
-	bits = boot_cpu_data.x86_coreid_bits;
-	cores = 1 << bits;
-	apicid_base = 0;
+	cores = topology_get_domain_size(TOPO_CORE_DOMAIN);
 
-	/*
-	 * get boot-time SMP configuration:
-	 */
-	early_get_smp_config();
+	apicid = boot_cpu_physical_apicid;
+	if (apicid > 0)
+		pr_info("BSP APIC ID: %02x\n", apicid);
 
-	if (boot_cpu_physical_apicid > 0) {
-		pr_info("BSP APIC ID: %02x\n", boot_cpu_physical_apicid);
-		apicid_base = boot_cpu_physical_apicid;
+	for_each_node_mask(i, numa_nodes_parsed) {
+		for (j = 0; j < cores; j++, apicid++)
+			set_apicid_to_node(apicid, i);
 	}
-
-	for_each_node_mask(i, numa_nodes_parsed)
-		for (j = apicid_base; j < cores + apicid_base; j++)
-			set_apicid_to_node((i << bits) + j, i);
-
 	return 0;
 }

arch/x86/platform/ce4100/ce4100.c

···
  */
 void __init x86_ce4100_early_setup(void)
 {
-	x86_init.oem.arch_setup = sdv_arch_setup;
-	x86_init.resources.probe_roms = x86_init_noop;
-	x86_init.mpparse.get_smp_config = x86_init_uint_noop;
-	x86_init.mpparse.find_smp_config = x86_init_noop;
-	x86_init.mpparse.setup_ioapic_ids = setup_ioapic_ids_from_mpc_nocheck;
-	x86_init.pci.init = ce4100_pci_init;
-	x86_init.pci.init_irq = sdv_pci_init;
+	x86_init.oem.arch_setup			= sdv_arch_setup;
+	x86_init.resources.probe_roms		= x86_init_noop;
+	x86_init.mpparse.find_mptable		= x86_init_noop;
+	x86_init.mpparse.early_parse_smp_cfg	= x86_init_noop;
+	x86_init.mpparse.parse_smp_cfg		= x86_dtb_parse_smp_config;
+	x86_init.pci.init			= ce4100_pci_init;
+	x86_init.pci.init_irq			= sdv_pci_init;
 
 	/*
 	 * By default, the reboot method is ACPI which is supported by the

arch/x86/platform/intel-mid/intel-mid.c

···
 	machine_ops.emergency_restart  = intel_mid_reboot;
 
 	/* Avoid searching for BIOS MP tables */
-	x86_init.mpparse.find_smp_config = x86_init_noop;
-	x86_init.mpparse.get_smp_config = x86_init_uint_noop;
+	x86_init.mpparse.find_mptable		= x86_init_noop;
+	x86_init.mpparse.early_parse_smp_cfg	= x86_init_noop;
+	x86_init.mpparse.parse_smp_cfg		= x86_init_noop;
 	set_bit(MP_BUS_ISA, mp_bus_not_pci);
 }

arch/x86/xen/apic.c

···
 	return 0xfd;
 }
 
-static u32 xen_set_apic_id(u32 x)
-{
-	WARN_ON(1);
-	return x;
-}
-
 static u32 xen_get_apic_id(u32 x)
 {
 	return ((x)>>24) & 0xFFu;
···
 	struct xen_platform_op op = {
 		.cmd = XENPF_get_cpuinfo,
 		.interface_version = XENPF_INTERFACE_VERSION,
-		.u.pcpu_info.xen_cpuid = 0,
 	};
-	int ret;
-
-	/* Shouldn't need this as APIC is turned off for PV, and we only
-	 * get called on the bootup processor. But just in case. */
-	if (!xen_initial_domain() || smp_processor_id())
-		return 0;
+	int ret, cpu;
 
 	if (reg == APIC_LVR)
 		return 0x14;
 	if (reg != APIC_ID)
 		return 0;
+
+	cpu = smp_processor_id();
+	if (!xen_initial_domain())
+		return cpu ? cpuid_to_apicid[cpu] << 24 : 0;
+
+	op.u.pcpu_info.xen_cpuid = cpu;
 
 	ret = HYPERVISOR_platform_op(&op);
 	if (ret)
···
 	return xen_pv_domain();
 }
 
-static u32 xen_phys_pkg_id(u32 initial_apic_id, int index_msb)
-{
-	return initial_apic_id >> index_msb;
-}
-
 static u32 xen_cpu_present_to_apicid(int cpu)
 {
 	if (cpu_present(cpu))
···
 	.disable_esr			= 0,
 
 	.cpu_present_to_apicid		= xen_cpu_present_to_apicid,
-	.phys_pkg_id			= xen_phys_pkg_id, /* detect_ht */
 
 	.max_apic_id			= UINT_MAX,
 	.get_apic_id			= xen_get_apic_id,
-	.set_apic_id			= xen_set_apic_id,
 
 	.calc_dest_apicid		= apic_flat_calc_apicid,
 

arch/x86/xen/enlighten_hvm.c

···
 	 */
 	xen_uninit_lock_cpu(cpu);
 
-	if (cpu_acpi_id(cpu) != U32_MAX)
+	if (cpu_acpi_id(cpu) != CPU_ACPIID_INVALID)
 		per_cpu(xen_vcpu_id, cpu) = cpu_acpi_id(cpu);
 	else
 		per_cpu(xen_vcpu_id, cpu) = cpu;

arch/x86/xen/enlighten_pv.c

···
 		xen_set_mtrr_data();
 	else
 		mtrr_overwrite_state(NULL, 0, MTRR_TYPE_WRBACK);
+
+	/* Adjust nr_cpu_ids before "enumeration" happens */
+	xen_smp_count_cpus();
 }
 
 static void __init xen_pv_guest_late_init(void)

arch/x86/xen/smp.c

···
 {
 	if (xen_hvm_domain())
 		native_smp_cpus_done(max_cpus);
-	else
-		calculate_max_logical_packages();
 }
 
 void xen_smp_send_reschedule(int cpu)

arch/x86/xen/smp.h

···
 int xen_smp_intr_init_pv(unsigned int cpu);
 void xen_smp_intr_free_pv(unsigned int cpu);
 
+void xen_smp_count_cpus(void);
 void xen_smp_cpus_done(unsigned int max_cpus);
 
 void xen_smp_send_reschedule(int cpu);
···
 	return 0;
 }
 static inline void xen_smp_intr_free_pv(unsigned int cpu) {}
+static inline void xen_smp_count_cpus(void) { }
 #endif /* CONFIG_SMP */
 
 #endif

arch/x86/xen/smp_pv.c

···
 #include <asm/idtentry.h>
 #include <asm/desc.h>
 #include <asm/cpu.h>
+#include <asm/apic.h>
 #include <asm/io_apic.h>
 
 #include <xen/interface/xen.h>
···
 	}
 	cpu = smp_processor_id();
 	smp_store_cpu_info(cpu);
-	cpu_data(cpu).x86_max_cores = 1;
 	set_cpu_sibling_map(cpu);
 
 	speculative_store_bypass_ht_init();
···
 	return rc;
 }
 
-static void __init _get_smp_config(unsigned int early)
+static void __init xen_pv_smp_config(void)
 {
-	int i, rc;
-	unsigned int subtract = 0;
+	u32 apicid = 0;
+	int i;
 
-	if (early)
-		return;
+	topology_register_boot_apic(apicid++);
 
-	num_processors = 0;
-	disabled_cpus = 0;
-	for (i = 0; i < nr_cpu_ids; i++) {
-		rc = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL);
-		if (rc >= 0) {
-			num_processors++;
-			set_cpu_possible(i, true);
-		} else {
-			set_cpu_possible(i, false);
-			set_cpu_present(i, false);
-			subtract++;
-		}
-	}
-#ifdef CONFIG_HOTPLUG_CPU
-	/* This is akin to using 'nr_cpus' on the Linux command line.
-	 * Which is OK as when we use 'dom0_max_vcpus=X' we can only
-	 * have up to X, while nr_cpu_ids is greater than X. This
-	 * normally is not a problem, except when CPU hotplugging
-	 * is involved and then there might be more than X CPUs
-	 * in the guest - which will not work as there is no
-	 * hypercall to expand the max number of VCPUs an already
-	 * running guest has. So cap it up to X. */
-	if (subtract)
-		set_nr_cpu_ids(nr_cpu_ids - subtract);
-#endif
+	for (i = 1; i < nr_cpu_ids; i++)
+		topology_register_apic(apicid++, CPU_ACPIID_INVALID, true);
+
 	/* Pretend to be a proper enumerated system */
 	smp_found_config = 1;
 }
···
 	xen_init_lock_cpu(0);
 
 	smp_prepare_cpus_common();
-
-	cpu_data(0).x86_max_cores = 1;
 
 	speculative_store_bypass_ht_init();
 
···
 	return IRQ_HANDLED;
 }
 
+void __init xen_smp_count_cpus(void)
+{
+	unsigned int cpus;
+
+	for (cpus = 0; cpus < nr_cpu_ids; cpus++) {
+		if (HYPERVISOR_vcpu_op(VCPUOP_is_up, cpus, NULL) < 0)
+			break;
+	}
+
+	pr_info("Xen PV: Detected %u vCPUS\n", cpus);
+	if (cpus < nr_cpu_ids)
+		set_nr_cpu_ids(cpus);
+}
+
 static const struct smp_ops xen_smp_ops __initconst = {
 	.smp_prepare_boot_cpu = xen_pv_smp_prepare_boot_cpu,
 	.smp_prepare_cpus = xen_pv_smp_prepare_cpus,
···
 	smp_ops = xen_smp_ops;
 
 	/* Avoid searching for BIOS MP tables */
-	x86_init.mpparse.find_smp_config = x86_init_noop;
-	x86_init.mpparse.get_smp_config = _get_smp_config;
+	x86_init.mpparse.find_mptable		= x86_init_noop;
+	x86_init.mpparse.early_parse_smp_cfg	= x86_init_noop;
+
+	/* XEN/PV Dom0 has halfways sane topology information via CPUID/MADT */
+	if (xen_initial_domain())
+		x86_init.mpparse.parse_smp_cfg	= x86_init_noop;
+	else
+		x86_init.mpparse.parse_smp_cfg	= xen_pv_smp_config;
 }

drivers/edac/amd64_edac.c

···
 /* On F10h and later ErrAddr is MC4_ADDR[47:1] */
 static u64 get_error_address(struct amd64_pvt *pvt, struct mce *m)
 {
-	u16 mce_nid = topology_die_id(m->extcpu);
+	u16 mce_nid = topology_amd_node_id(m->extcpu);
 	struct mem_ctl_info *mci;
 	u8 start_bit = 1;
 	u8 end_bit   = 47;
···
 	int cpu;
 
 	for_each_online_cpu(cpu)
-		if (topology_die_id(cpu) == nid)
+		if (topology_amd_node_id(cpu) == nid)
 			cpumask_set_cpu(cpu, mask);
 }
 

drivers/edac/mce_amd.c

···
 static void decode_mc4_mce(struct mce *m)
 {
 	unsigned int fam = x86_family(m->cpuid);
-	int node_id = topology_die_id(m->extcpu);
+	int node_id = topology_amd_node_id(m->extcpu);
 	u16 ec = EC(m->status);
 	u8 xec = XEC(m->status, 0x1f);
 	u8 offset = 0;
···
 
 	if ((bank_type == SMCA_UMC || bank_type == SMCA_UMC_V2) &&
 	    xec == 0 && decode_dram_ecc)
-		decode_dram_ecc(topology_die_id(m->extcpu), m);
+		decode_dram_ecc(topology_amd_node_id(m->extcpu), m);
 }
 
 static inline void amd_decode_err_code(u16 ec)

drivers/gpu/drm/amd/pm/swsmu/smu11/vangogh_ppt.c

···
 
 #ifdef CONFIG_X86
 	/* AMD x86 APU only */
-	smu->cpu_core_num = boot_cpu_data.x86_max_cores;
+	smu->cpu_core_num = topology_num_cores_per_package();
 #else
 	smu->cpu_core_num = 4;
 #endif

drivers/hwmon/coretemp.c

···
 	if (!x86_match_cpu(coretemp_ids))
 		return -ENODEV;
 
-	max_zones = topology_max_packages() * topology_max_die_per_package();
+	max_zones = topology_max_packages() * topology_max_dies_per_package();
 	zone_devices = kcalloc(max_zones, sizeof(struct platform_device *),
 			      GFP_KERNEL);
 	if (!zone_devices)

drivers/hwmon/fam15h_power.c

···
 	 * With the new x86 topology modelling, x86_max_cores is the
 	 * compute unit number.
 	 */
-	cu_num = boot_cpu_data.x86_max_cores;
+	cu_num = topology_num_cores_per_package();
 
 	ret = read_registers(data);
 	if (ret)

drivers/platform/x86/intel/uncore-frequency/uncore-frequency.c

···
 		return -ENODEV;
 
 	uncore_max_entries = topology_max_packages() *
-					topology_max_die_per_package();
+					topology_max_dies_per_package();
 	uncore_instances = kcalloc(uncore_max_entries,
 				   sizeof(*uncore_instances), GFP_KERNEL);
 	if (!uncore_instances)

drivers/powercap/intel_rapl_common.c

···
 	if (id_is_cpu) {
 		rp->id = topology_logical_die_id(id);
 		rp->lead_cpu = id;
-		if (topology_max_die_per_package() > 1)
+		if (topology_max_dies_per_package() > 1)
 			snprintf(rp->name, PACKAGE_DOMAIN_NAME_LENGTH, "package-%d-die-%d",
 				 topology_physical_package_id(id), topology_die_id(id));
 		else

drivers/thermal/intel/intel_hfi.c

···
 
 	/* There is one HFI instance per die/package. */
 	max_hfi_instances = topology_max_packages() *
-			    topology_max_die_per_package();
+			    topology_max_dies_per_package();
 
 	/*
 	 * This allocation may fail. CPU hotplug callbacks must check

drivers/thermal/intel/intel_powerclamp.c

···
 	poll_pkg_cstate_enable = false;
 	if (cpumask_equal(cpu_present_mask, idle_injection_cpu_mask)) {
 		ii_dev = idle_inject_register_full(idle_injection_cpu_mask, idle_inject_update);
-		if (topology_max_packages() == 1 && topology_max_die_per_package() == 1)
+		if (topology_max_packages() == 1 && topology_max_dies_per_package() == 1)
 			poll_pkg_cstate_enable = true;
 	} else {
 		ii_dev = idle_inject_register(idle_injection_cpu_mask);

drivers/thermal/intel/x86_pkg_temp_thermal.c

···
 	if (!x86_match_cpu(pkg_temp_thermal_ids))
 		return -ENODEV;
 
-	max_id = topology_max_packages() * topology_max_die_per_package();
+	max_id = topology_max_packages() * topology_max_dies_per_package();
 	zones = kcalloc(max_id, sizeof(struct zone_device *),
 			   GFP_KERNEL);
 	if (!zones)

include/linux/cpu.h

···
 extern void cpu_maps_update_begin(void);
 extern void cpu_maps_update_done(void);
 int bringup_hibernate_cpu(unsigned int sleep_cpu);
-void bringup_nonboot_cpus(unsigned int setup_max_cpus);
+void bringup_nonboot_cpus(unsigned int max_cpus);
 
 #else	/* CONFIG_SMP */
 #define cpuhp_tasks_frozen	0

include/linux/smp.h

···
 static inline void kick_all_cpus_sync(void) {  }
 static inline void wake_up_all_idle_cpus(void) {  }
 
+#define setup_max_cpus 0
+
 #ifdef CONFIG_UP_LATE_INIT
 extern void __init up_late_init(void);
 static inline void smp_init(void) { up_late_init(); }

init/main.c

···
 __setup("rdinit=", rdinit_setup);
 
 #ifndef CONFIG_SMP
-static const unsigned int setup_max_cpus = NR_CPUS;
 static inline void setup_nr_cpu_ids(void) { }
 static inline void smp_prepare_cpus(unsigned int maxcpus) { }
 #endif

kernel/cpu.c

···
 static inline bool cpuhp_bringup_cpus_parallel(unsigned int ncpus) { return false; }
 #endif /* CONFIG_HOTPLUG_PARALLEL */
 
-void __init bringup_nonboot_cpus(unsigned int setup_max_cpus)
+void __init bringup_nonboot_cpus(unsigned int max_cpus)
 {
 	/* Try parallel bringup optimization if enabled */
-	if (cpuhp_bringup_cpus_parallel(setup_max_cpus))
+	if (cpuhp_bringup_cpus_parallel(max_cpus))
 		return;
 
 	/* Full per CPU serialized bringup */
-	cpuhp_bringup_mask(cpu_present_mask, setup_max_cpus, CPUHP_ONLINE);
+	cpuhp_bringup_mask(cpu_present_mask, max_cpus, CPUHP_ONLINE);
 }
 
 #ifdef CONFIG_PM_SLEEP_SMP