Merge branch 'for-next/spectre-bhb' into for-next/core

[platform/kernel/linux-starfive.git] / arch / arm64 / kernel / cpufeature.c

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 32aa0eb..d72c4b4 100644 (file)
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -73,6 +73,8 @@
 #include <linux/mm.h>
 #include <linux/cpu.h>
 #include <linux/kasan.h>
+#include <linux/percpu.h>
+
 #include <asm/cpu.h>
 #include <asm/cpufeature.h>
 #include <asm/cpu_ops.h>
@@ -85,6 +87,7 @@
 #include <asm/smp.h>
 #include <asm/sysreg.h>
 #include <asm/traps.h>
+#include <asm/vectors.h>
 #include <asm/virt.h>
 
 /* Kernel representation of AT_HWCAP and AT_HWCAP2 */
@@ -110,6 +113,8 @@ DECLARE_BITMAP(boot_capabilities, ARM64_NPATCHABLE);
 bool arm64_use_ng_mappings = false;
 EXPORT_SYMBOL(arm64_use_ng_mappings);
 
+DEFINE_PER_CPU_READ_MOSTLY(const char *, this_cpu_vector) = vectors;
+
 /*
  * Permit PER_LINUX32 and execve() of 32-bit binaries even if not all CPUs
  * support it?
@@ -226,6 +231,7 @@ static const struct arm64_ftr_bits ftr_id_aa64isar1[] = {
 };
 
 static const struct arm64_ftr_bits ftr_id_aa64isar2[] = {
+       ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64ISAR2_CLEARBHB_SHIFT, 4, 0),
        ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
                       FTR_STRICT, FTR_EXACT, ID_AA64ISAR2_APA3_SHIFT, 4, 0),
        ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH),
@@ -1599,6 +1605,12 @@ kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
 
        int cpu = smp_processor_id();
 
+       if (__this_cpu_read(this_cpu_vector) == vectors) {
+               const char *v = arm64_get_bp_hardening_vector(EL1_VECTOR_KPTI);
+
+               __this_cpu_write(this_cpu_vector, v);
+       }
+
        /*
         * We don't need to rewrite the page-tables if either we've done
         * it already or we have KASLR enabled and therefore have not