diff options
| author | James Morse <james.morse@arm.com> | 2022-03-31 19:33:58 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-04-02 12:41:10 +0200 |
| commit | 067b8175245d97dacb5d459ef10ab7639916d7c9 (patch) | |
| tree | 5d1ae7a333cf3539831b975621be92a5f82333be | |
| parent | 3e3904125fccd042fda24294624e8f66699fd06d (diff) | |
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 | 6 | ||||
| -rw-r--r-- | arch/arm64/include/asm/kvm_host.h | 5 | ||||
| -rw-r--r-- | virt/kvm/arm/psci.c | 12 |
3 files changed, 23 insertions, 0 deletions
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index b60232639984..dbd9615b428c 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 @@ -324,4 +325,9 @@ static inline int kvm_arm_have_ssbd(void) return KVM_SSBD_UNKNOWN; } +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 8d94404829f0..be82119ed24a 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -450,4 +450,9 @@ static inline int kvm_arm_have_ssbd(void) } } +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 c95ab4c5a475..129b755824e1 100644 --- a/virt/kvm/arm/psci.c +++ b/virt/kvm/arm/psci.c @@ -433,6 +433,18 @@ 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: |