Expose a capability keying the hVHE feature as well as a new
predicate testing it. Nothing is so far using it, and nothing
is enabling it yet.
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
arch/arm64/include/asm/cpufeature.h | 1 +
arch/arm64/include/asm/virt.h | 8 ++++++++
arch/arm64/kernel/cpufeature.c | 15 +++++++++++++++
arch/arm64/tools/cpucaps | 1 +
4 files changed, 25 insertions(+)
diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h
index f44a7860636f..2d41015429b3 100644
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -16,6 +16,7 @@
#define cpu_feature(x) KERNEL_HWCAP_ ## x
#define ARM64_SW_FEATURE_OVERRIDE_NOKASLR 0
+#define ARM64_SW_FEATURE_OVERRIDE_HVHE 4
#ifndef __ASSEMBLY__
diff --git a/arch/arm64/include/asm/virt.h b/arch/arm64/include/asm/virt.h
index 4eb601e7de50..b11a1c8c8b36 100644
--- a/arch/arm64/include/asm/virt.h
+++ b/arch/arm64/include/asm/virt.h
@@ -140,6 +140,14 @@ static __always_inline bool is_protected_kvm_enabled(void)
return cpus_have_final_cap(ARM64_KVM_PROTECTED_MODE);
}
+static __always_inline bool has_hvhe(void)
+{
+ if (is_vhe_hyp_code())
+ return false;
+
+ return cpus_have_final_cap(ARM64_KVM_HVHE);
+}
+
static inline bool is_hyp_nvhe(void)
{
return is_hyp_mode_available() && !is_kernel_in_hyp_mode();
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index a3959e9f7d55..efac89c4c548 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -1932,6 +1932,15 @@ static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused)
write_sysreg(read_sysreg(tpidr_el1), tpidr_el2);
}
+static bool hvhe_possible(const struct arm64_cpu_capabilities *entry,
+ int __unused)
+{
+ u64 val;
+
+ val = arm64_sw_feature_override.val & arm64_sw_feature_override.mask;
+ return cpuid_feature_extract_unsigned_field(val, ARM64_SW_FEATURE_OVERRIDE_HVHE);
+}
+
#ifdef CONFIG_ARM64_PAN
static void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused)
{
@@ -2642,6 +2651,12 @@ static const struct arm64_cpu_capabilities arm64_features[] = {
.matches = has_cpuid_feature,
.cpu_enable = cpu_trap_el0_impdef,
},
+ {
+ .desc = "VHE for hypervisor only",
+ .capability = ARM64_KVM_HVHE,
+ .type = ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE,
+ .matches = hvhe_possible,
+ },
{},
};
diff --git a/arch/arm64/tools/cpucaps b/arch/arm64/tools/cpucaps
index f1c0347ec31a..cee2be85b89b 100644
--- a/arch/arm64/tools/cpucaps
+++ b/arch/arm64/tools/cpucaps
@@ -43,6 +43,7 @@ HAS_TLB_RANGE
HAS_VIRT_HOST_EXTN
HAS_WFXT
HW_DBM
+KVM_HVHE
KVM_PROTECTED_MODE
MISMATCHED_CACHE_TYPE
MTE
--
2.34.1
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