| Message ID | 1436372356-30410-4-git-send-email-marc.zyngier@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Jul 08, 2015 at 05:19:06PM +0100, Marc Zyngier wrote: > Add a new ARM64_HAS_VIRT_HOST_EXTN features to indicate that the > CPU has the ARMv8,1 VHE capability. Nit: s/,/./ It's probably worth mentioning somewhere that we have to check CurrentEL rather than a feature register in case some prior software dropped us to EL1N (e.g. if we're a guest under this scheme). Mark. > > This will be used to trigger kernel patching in KVM. > > Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> > --- > 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 > > _______________________________________________ > kvmarm mailing list > kvmarm@lists.cs.columbia.edu > https://lists.cs.columbia.edu/mailman/listinfo/kvmarm > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 09/07/15 10:48, Mark Rutland wrote: > On Wed, Jul 08, 2015 at 05:19:06PM +0100, Marc Zyngier wrote: >> Add a new ARM64_HAS_VIRT_HOST_EXTN features to indicate that the >> CPU has the ARMv8,1 VHE capability. > > Nit: s/,/./ > > It's probably worth mentioning somewhere that we have to check CurrentEL > rather than a feature register in case some prior software dropped us to > EL1N (e.g. if we're a guest under this scheme). Good point, this is a leftover from a previous version that actually checked the feature register. I'll clean up the commit log. Thanks, M. > Mark. > >> >> This will be used to trigger kernel patching in KVM. >> >> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> >> --- >> 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 >> >> _______________________________________________ >> kvmarm mailing list >> kvmarm@lists.cs.columbia.edu >> https://lists.cs.columbia.edu/mailman/listinfo/kvmarm >> >
On Wed, Jul 08, 2015 at 05:19:06PM +0100, Marc Zyngier wrote: > 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 <marc.zyngier@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Will -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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, + }, {}, };
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 <marc.zyngier@arm.com> --- arch/arm64/include/asm/cpufeature.h | 3 ++- arch/arm64/kernel/cpufeature.c | 11 +++++++++++ 2 files changed, 13 insertions(+), 1 deletion(-)