Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Catalin Marinas:

- In copy_highpage(), only reset the tag of the destination pointer if
KASAN_HW_TAGS is enabled so that user-space MTE does not interfere
with KASAN_SW_TAGS (which relies on top-byte-ignore).

- Remove warning if SME is detected without SVE, the kernel can cope
with such configuration (though none in the field currently).

- In cfi_handler(), pass the ESR_EL1 value to die() for consistency
with other die() callers.

- Disable HUGETLB_PAGE_OPTIMIZE_VMEMMAP on arm64 since the pte
manipulation from the generic vmemmap_remap_pte() does not follow the
required ARM break-before-make sequence (clear the pte, flush the
TLBs, set the new pte). It may be re-enabled once this sequence is
sorted.

- Fix possible memory leak in the arm64 ACPI code if the SMCCC version
and conduit checks fail.

- Forbid CALL_OPS with CC_OPTIMIZE_FOR_SIZE since gcc ignores
-falign-functions=N with -Os.

- Don't pretend KASLR is enabled if offset < MIN_KIMG_ALIGN as no
randomisation would actually take place.

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: kaslr: don't pretend KASLR is enabled if offset < MIN_KIMG_ALIGN
arm64: ftrace: forbid CALL_OPS with CC_OPTIMIZE_FOR_SIZE
arm64: acpi: Fix possible memory leak of ffh_ctxt
arm64: mm: hugetlb: Disable HUGETLB_PAGE_OPTIMIZE_VMEMMAP
arm64: pass ESR_ELx to die() of cfi_handler
arm64/fpsimd: Remove warning for SME without SVE
arm64: Reset KASAN tag in copy_highpage with HW tags only

arch/arm64/Kconfig

···
 	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
 	select ARCH_WANT_FRAME_POINTERS
 	select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
-	select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
 	select ARCH_WANT_LD_ORPHAN_WARN
 	select ARCH_WANTS_NO_INSTR
 	select ARCH_WANTS_THP_SWAP if ARM64_4K_PAGES
···
 	select HAVE_DMA_CONTIGUOUS
 	select HAVE_DYNAMIC_FTRACE
 	select HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS \
-		if (DYNAMIC_FTRACE_WITH_ARGS && !CFI_CLANG)
+		if (DYNAMIC_FTRACE_WITH_ARGS && !CFI_CLANG && \
+		    !CC_OPTIMIZE_FOR_SIZE)
 	select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
 		if DYNAMIC_FTRACE_WITH_ARGS
 	select HAVE_EFFICIENT_UNALIGNED_ACCESS

arch/arm64/include/asm/memory.h

···
 #include <linux/compiler.h>
 #include <linux/mmdebug.h>
 #include <linux/types.h>
+#include <asm/boot.h>
 #include <asm/bug.h>
 
 #if VA_BITS > 48
···
 static inline unsigned long kaslr_offset(void)
 {
 	return kimage_vaddr - KIMAGE_VADDR;
+}
+
+static inline bool kaslr_enabled(void)
+{
+	/*
+	 * The KASLR offset modulo MIN_KIMG_ALIGN is taken from the physical
+	 * placement of the image rather than from the seed, so a displacement
+	 * of less than MIN_KIMG_ALIGN means that no seed was provided.
+	 */
+	return kaslr_offset() >= MIN_KIMG_ALIGN;
 }
 
 /*

arch/arm64/kernel/acpi.c

···
 	enum arm_smccc_conduit conduit;
 	struct acpi_ffh_data *ffh_ctxt;
 
-	ffh_ctxt = kzalloc(sizeof(*ffh_ctxt), GFP_KERNEL);
-	if (!ffh_ctxt)
-		return -ENOMEM;
-
 	if (arm_smccc_get_version() < ARM_SMCCC_VERSION_1_2)
 		return -EOPNOTSUPP;
 
···
 		pr_err("%s: invalid SMCCC conduit\n", __func__);
 		return -EOPNOTSUPP;
 	}
+
+	ffh_ctxt = kzalloc(sizeof(*ffh_ctxt), GFP_KERNEL);
+	if (!ffh_ctxt)
+		return -ENOMEM;
 
 	if (conduit == SMCCC_CONDUIT_SMC) {
 		ffh_ctxt->invoke_ffh_fn = __arm_smccc_smc;

arch/arm64/kernel/cpufeature.c

···
 			return false;
 	}
 
-	return kaslr_offset() > 0;
+	return kaslr_enabled();
 }
 
 static bool __meltdown_safe = true;

arch/arm64/kernel/fpsimd.c

···
 		pr_notice("Advanced SIMD is not implemented\n");
 
 
-	if (cpu_have_named_feature(SME) && !cpu_have_named_feature(SVE))
-		pr_notice("SME is implemented but not SVE\n");
-
 	sve_sysctl_init();
 	sme_sysctl_init();
 

arch/arm64/kernel/kaslr.c

···
 		return 0;
 	}
 
-	if (!kaslr_offset()) {
+	if (!kaslr_enabled()) {
 		pr_warn("KASLR disabled due to lack of seed\n");
 		return 0;
 	}

arch/arm64/kernel/traps.c

···
 
 	switch (report_cfi_failure(regs, regs->pc, &target, type)) {
 	case BUG_TRAP_TYPE_BUG:
-		die("Oops - CFI", regs, 0);
+		die("Oops - CFI", regs, esr);
 		break;
 
 	case BUG_TRAP_TYPE_WARN:

arch/arm64/mm/copypage.c

···
 	copy_page(kto, kfrom);
 
 	if (system_supports_mte() && page_mte_tagged(from)) {
-		page_kasan_tag_reset(to);
+		if (kasan_hw_tags_enabled())
+			page_kasan_tag_reset(to);
 		/* It's a new page, shouldn't have been tagged yet */
 		WARN_ON_ONCE(!try_page_mte_tagging(to));
 		mte_copy_page_tags(kto, kfrom);