[PATCH 03/13] arm64: Add ARM64_HAS_VIRT_HOST_EXTN feature
From: Marc Zyngier <hidden>
Date: 2015-07-08 16:19:41
Also in:
kvm, kvmarm, lkml
Subsystem:
arm64 port (aarch64 architecture), the rest · Maintainers:
Catalin Marinas, Will Deacon, Linus Torvalds
Add a new ARM64_HAS_VIRT_HOST_EXTN features to indicate that the CPU has the ARMv8,1 VHE capability. This will be used to trigger kernel patching in KVM. Signed-off-by: Marc Zyngier <redacted> --- arch/arm64/include/asm/cpufeature.h | 3 ++- arch/arm64/kernel/cpufeature.c | 11 +++++++++++ 2 files changed, 13 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h
index c104421..6c3742d 100644
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h@@ -25,8 +25,9 @@ #define ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE 1 #define ARM64_WORKAROUND_845719 2 #define ARM64_HAS_SYSREG_GIC_CPUIF 3 +#define ARM64_HAS_VIRT_HOST_EXTN 4 -#define ARM64_NCAPS 4 +#define ARM64_NCAPS 5 #ifndef __ASSEMBLY__
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 5ad86ce..e1dcd63 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c@@ -21,6 +21,7 @@ #include <linux/types.h> #include <asm/cpu.h> #include <asm/cpufeature.h> +#include <asm/virt.h> static bool has_id_aa64pfr0_feature(const struct arm64_cpu_capabilities *entry)
@@ -31,6 +32,11 @@ has_id_aa64pfr0_feature(const struct arm64_cpu_capabilities *entry) return (val & entry->register_mask) == entry->register_value; } +static bool runs_at_el2(const struct arm64_cpu_capabilities *entry) +{ + return is_kernel_in_hyp_mode(); +} + static const struct arm64_cpu_capabilities arm64_features[] = { { .desc = "GIC system register CPU interface",
@@ -39,6 +45,11 @@ static const struct arm64_cpu_capabilities arm64_features[] = { .register_mask = (0xf << 24), .register_value = (1 << 24), }, + { + .desc = "Virtualization Host Extensions", + .capability = ARM64_HAS_VIRT_HOST_EXTN, + .matches = runs_at_el2, + }, {}, };
--
2.1.4