1 files changed, 43 insertions, 4 deletions

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 39138f6d3ba2..e99eddec0a46 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -70,10 +70,12 @@
 #include <linux/types.h>
 #include <linux/mm.h>
 #include <linux/cpu.h>
+#include <linux/kasan.h>
 #include <asm/cpu.h>
 #include <asm/cpufeature.h>
 #include <asm/cpu_ops.h>
 #include <asm/fpsimd.h>
+#include <asm/kvm_host.h>
 #include <asm/mmu_context.h>
 #include <asm/mte.h>
 #include <asm/processor.h>
@@ -1709,9 +1711,26 @@ static void cpu_enable_mte(struct arm64_cpu_capabilities const *cap)
 		cleared_zero_page = true;
 		mte_clear_page_tags(lm_alias(empty_zero_page));
 	}
+
+	kasan_init_hw_tags_cpu();
 }
 #endif /* CONFIG_ARM64_MTE */
 
+#ifdef CONFIG_KVM
+static bool is_kvm_protected_mode(const struct arm64_cpu_capabilities *entry, int __unused)
+{
+	if (kvm_get_mode() != KVM_MODE_PROTECTED)
+		return false;
+
+	if (is_kernel_in_hyp_mode()) {
+		pr_warn("Protected KVM not available with VHE\n");
+		return false;
+	}
+
+	return true;
+}
+#endif /* CONFIG_KVM */
+
 /* Internal helper functions to match cpu capability type */
 static bool
 cpucap_late_cpu_optional(const struct arm64_cpu_capabilities *cap)
@@ -1803,6 +1822,12 @@ static const struct arm64_cpu_capabilities arm64_features[] = {
 		.field_pos = ID_AA64PFR0_EL1_SHIFT,
 		.min_field_value = ID_AA64PFR0_EL1_32BIT_64BIT,
 	},
+	{
+		.desc = "Protected KVM",
+		.capability = ARM64_KVM_PROTECTED_MODE,
+		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
+		.matches = is_kvm_protected_mode,
+	},
 #endif
 	{
 		.desc = "Kernel page table isolation (KPTI)",
@@ -2543,7 +2568,7 @@ static void verify_hyp_capabilities(void)
 	int parange, ipa_max;
 	unsigned int safe_vmid_bits, vmid_bits;
 
-	if (!IS_ENABLED(CONFIG_KVM) || !IS_ENABLED(CONFIG_KVM_ARM_HOST))
+	if (!IS_ENABLED(CONFIG_KVM))
 		return;
 
 	safe_mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
@@ -2831,14 +2856,28 @@ static int __init enable_mrs_emulation(void)
 
 core_initcall(enable_mrs_emulation);
 
+enum mitigation_state arm64_get_meltdown_state(void)
+{
+	if (__meltdown_safe)
+		return SPECTRE_UNAFFECTED;
+
+	if (arm64_kernel_unmapped_at_el0())
+		return SPECTRE_MITIGATED;
+
+	return SPECTRE_VULNERABLE;
+}
+
 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr,
 			  char *buf)
 {
-	if (__meltdown_safe)
+	switch (arm64_get_meltdown_state()) {
+	case SPECTRE_UNAFFECTED:
 		return sprintf(buf, "Not affected\n");
 
-	if (arm64_kernel_unmapped_at_el0())
+	case SPECTRE_MITIGATED:
 		return sprintf(buf, "Mitigation: PTI\n");
 
-	return sprintf(buf, "Vulnerable\n");
+	default:
+		return sprintf(buf, "Vulnerable\n");
+	}
 }