On 05/07/2020 03:50 PM, Marc Zyngier wrote: > On Thu, 7 May 2020 11:49:47 +0530 > Anshuman Khandual <anshuman.khand...@arm.com> wrote: > > Hi Anshuman,
Hi Marc, > >> This validates KVM capabilities like VMID width, IPA range for hotplug CPU >> against system finalized values. While here, it factors out get_vmid_bits() >> for general use and also defines ID_AA64MMFR0_PARANGE_MASK. > > nit: these are not KVM-specific capabilities, but general > virtualization features. Sure, will change as (s/kvm/hyp) instead and update the commit message here. > >> >> Cc: Catalin Marinas <catalin.mari...@arm.com> >> Cc: Will Deacon <w...@kernel.org> >> Cc: Marc Zyngier <m...@kernel.org> >> Cc: Mark Rutland <mark.rutl...@arm.com> >> Cc: James Morse <james.mo...@arm.com> >> Cc: Suzuki K Poulose <suzuki.poul...@arm.com> >> Cc: linux-arm-ker...@lists.infradead.org >> Cc: kvmarm@lists.cs.columbia.edu >> Cc: linux-ker...@vger.kernel.org >> >> Suggested-by: Suzuki Poulose <suzuki.poul...@arm.com> >> Signed-off-by: Anshuman Khandual <anshuman.khand...@arm.com> >> --- >> arch/arm64/include/asm/cpufeature.h | 22 +++++++++++++++++++ >> arch/arm64/include/asm/kvm_mmu.h | 2 +- >> arch/arm64/include/asm/sysreg.h | 1 + >> arch/arm64/kernel/cpufeature.c | 2 ++ >> arch/arm64/kvm/reset.c | 33 +++++++++++++++++++++++++++-- >> 5 files changed, 57 insertions(+), 3 deletions(-) >> >> diff --git a/arch/arm64/include/asm/cpufeature.h >> b/arch/arm64/include/asm/cpufeature.h >> index afe08251ff95..6808a2091de4 100644 >> --- a/arch/arm64/include/asm/cpufeature.h >> +++ b/arch/arm64/include/asm/cpufeature.h >> @@ -745,6 +745,28 @@ static inline bool cpu_has_hw_af(void) >> extern bool cpu_has_amu_feat(int cpu); >> #endif >> >> +static inline unsigned int get_vmid_bits(u64 mmfr1) >> +{ >> + int vmid_bits; >> + >> + vmid_bits = cpuid_feature_extract_unsigned_field(mmfr1, >> + ID_AA64MMFR1_VMIDBITS_SHIFT); >> + if (vmid_bits == ID_AA64MMFR1_VMIDBITS_16) >> + return 16; >> + >> + /* >> + * Return the default here even if any reserved >> + * value is fetched from the system register. >> + */ >> + return 8; >> +} >> + >> +#ifdef CONFIG_KVM_ARM_HOST >> +void verify_kvm_capabilities(void); >> +#else >> +static inline void verify_kvm_capabilities(void) { } >> +#endif >> + >> #endif /* __ASSEMBLY__ */ >> >> #endif >> diff --git a/arch/arm64/include/asm/kvm_mmu.h >> b/arch/arm64/include/asm/kvm_mmu.h >> index 30b0e8d6b895..a7137e144b97 100644 >> --- a/arch/arm64/include/asm/kvm_mmu.h >> +++ b/arch/arm64/include/asm/kvm_mmu.h >> @@ -416,7 +416,7 @@ static inline unsigned int kvm_get_vmid_bits(void) >> { >> int reg = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1); >> >> - return (cpuid_feature_extract_unsigned_field(reg, >> ID_AA64MMFR1_VMIDBITS_SHIFT) == 2) ? 16 : 8; >> + return get_vmid_bits(reg); >> } >> >> /* >> diff --git a/arch/arm64/include/asm/sysreg.h >> b/arch/arm64/include/asm/sysreg.h index c4ac0ac25a00..3510a4668970 >> 100644 --- a/arch/arm64/include/asm/sysreg.h >> +++ b/arch/arm64/include/asm/sysreg.h >> @@ -705,6 +705,7 @@ >> #define ID_AA64MMFR0_TGRAN16_SUPPORTED 0x1 >> #define ID_AA64MMFR0_PARANGE_48 0x5 >> #define ID_AA64MMFR0_PARANGE_52 0x6 >> +#define ID_AA64MMFR0_PARANGE_MASK 0x7 >> >> #ifdef CONFIG_ARM64_PA_BITS_52 >> #define ID_AA64MMFR0_PARANGE_MAX ID_AA64MMFR0_PARANGE_52 >> diff --git a/arch/arm64/kernel/cpufeature.c >> b/arch/arm64/kernel/cpufeature.c index 9fac745aa7bb..041dd610b0f8 >> 100644 --- a/arch/arm64/kernel/cpufeature.c >> +++ b/arch/arm64/kernel/cpufeature.c >> @@ -2206,6 +2206,8 @@ static void verify_local_cpu_capabilities(void) >> >> if (system_supports_sve()) >> verify_sve_features(); >> + >> + verify_kvm_capabilities(); > > You should only check this if booted at EL2. Otherwise, it doesn't > really matter. Sure, will first check on is_hyp_mode_available() before calling into verify_kvm_capabilities(). > >> } >> >> void check_local_cpu_capabilities(void) >> diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c >> index 30b7ea680f66..1eebcc2a8396 100644 >> --- a/arch/arm64/kvm/reset.c >> +++ b/arch/arm64/kvm/reset.c >> @@ -340,11 +340,39 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu) >> return ret; >> } >> >> +void verify_kvm_capabilities(void) > > This is really in the wrong file. reset.c is supposed to contain things > that are meaningful to the guest reset state. This clearly isn't. I'd > suggest you add an accessor for the kvm_ipa_limit variable, and keep > the function next to the other verify_* functions in cpufeature.c. Sure, will do. _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm