[PATCH v4 05/23] arm64: Add ARM64_HAS_VIRT_HOST_EXTN feature
From: Marc Zyngier <hidden>
Date: 2016-02-11 18:48:04
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. Acked-by: Christoffer Dall <redacted> Acked-by: Catalin Marinas <catalin.marinas@arm.com> 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 8f271b8..c705d6a 100644
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h@@ -30,8 +30,9 @@ #define ARM64_HAS_LSE_ATOMICS 5 #define ARM64_WORKAROUND_CAVIUM_23154 6 #define ARM64_WORKAROUND_834220 7 +#define ARM64_HAS_VIRT_HOST_EXTN 8 -#define ARM64_NCAPS 8 +#define ARM64_NCAPS 9 #ifndef __ASSEMBLY__
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 5c90aa4..ba74519 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c@@ -26,6 +26,7 @@ #include <asm/cpu_ops.h> #include <asm/processor.h> #include <asm/sysreg.h> +#include <asm/virt.h> unsigned long elf_hwcap __read_mostly; EXPORT_SYMBOL_GPL(elf_hwcap);
@@ -621,6 +622,11 @@ static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry) return has_sre; } +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",
@@ -651,6 +657,11 @@ static const struct arm64_cpu_capabilities arm64_features[] = { .min_field_value = 2, }, #endif /* CONFIG_AS_LSE && CONFIG_ARM64_LSE_ATOMICS */ + { + .desc = "Virtualization Host Extensions", + .capability = ARM64_HAS_VIRT_HOST_EXTN, + .matches = runs_at_el2, + }, {}, };
--
2.1.4