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| author | James Morse <james.morse@arm.com> | 2022-03-18 17:48:40 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-03-23 09:10:43 +0100 |
| commit | 5f051d32b03f08a0507ac1afd7b9c0a30c8e5d59 (patch) | |
| tree | 68e898f7c0c2b453789c23f43fa8acd9f48902d4 | |
| parent | c20d551744797000c4af993f7d59ef8c69732949 (diff) | |
| download | linux-stable-5f051d32b03f08a0507ac1afd7b9c0a30c8e5d59.tar.gz linux-stable-5f051d32b03f08a0507ac1afd7b9c0a30c8e5d59.tar.bz2 linux-stable-5f051d32b03f08a0507ac1afd7b9c0a30c8e5d59.zip | |
KVM: arm64: Allow SMCCC_ARCH_WORKAROUND_3 to be discovered and migrated
commit a5905d6af492ee6a4a2205f0d550b3f931b03d03 upstream.
KVM allows the guest to discover whether the ARCH_WORKAROUND SMCCC are
implemented, and to preserve that state during migration through its
firmware register interface.
Add the necessary boiler plate for SMCCC_ARCH_WORKAROUND_3.
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
[ kvm code moved to virt/kvm/arm, removed fw regs ABI. Added 32bit stub ]
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/arm/include/asm/kvm_host.h | 7 | ||||
| -rw-r--r-- | arch/arm64/include/asm/kvm_host.h | 5 | ||||
| -rw-r--r-- | virt/kvm/arm/psci.c | 12 |
3 files changed, 24 insertions, 0 deletions
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index ae073fceb3f0..db20534912cd 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -26,6 +26,7 @@ #include <asm/kvm_asm.h> #include <asm/kvm_mmio.h> #include <asm/fpstate.h> +#include <asm/spectre.h> #include <kvm/arm_arch_timer.h> #define __KVM_HAVE_ARCH_INTC_INITIALIZED @@ -367,4 +368,10 @@ void kvm_arch_free_vm(struct kvm *kvm); #define kvm_arm_vcpu_loaded(vcpu) (false) +static inline int kvm_arm_get_spectre_bhb_state(void) +{ + /* 32bit guests don't need firmware for this */ + return SPECTRE_VULNERABLE; /* aka SMCCC_RET_NOT_SUPPORTED */ +} + #endif /* __ARM_KVM_HOST_H__ */ diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 07472c138ced..7e1b19ea07ea 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -542,4 +542,9 @@ void kvm_arch_free_vm(struct kvm *kvm); #define kvm_arm_vcpu_loaded(vcpu) ((vcpu)->arch.sysregs_loaded_on_cpu) +static inline enum mitigation_state kvm_arm_get_spectre_bhb_state(void) +{ + return arm64_get_spectre_bhb_state(); +} + #endif /* __ARM64_KVM_HOST_H__ */ diff --git a/virt/kvm/arm/psci.c b/virt/kvm/arm/psci.c index 34d08ee63747..a161951e55a5 100644 --- a/virt/kvm/arm/psci.c +++ b/virt/kvm/arm/psci.c @@ -429,6 +429,18 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) break; } break; + case ARM_SMCCC_ARCH_WORKAROUND_3: + switch (kvm_arm_get_spectre_bhb_state()) { + case SPECTRE_VULNERABLE: + break; + case SPECTRE_MITIGATED: + val = SMCCC_RET_SUCCESS; + break; + case SPECTRE_UNAFFECTED: + val = SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED; + break; + } + break; } break; default: |