diff options
| author | James Morse <james.morse@arm.com> | 2022-04-06 17:45:44 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-04-12 07:52:17 +0200 |
| commit | df0448480b9c2f0a2f5a5055e04afa80bf0a5301 (patch) | |
| tree | 24dab2d8db207c797322b0aa7f6d0737a0fb2c1d | |
| parent | 4dd8aae585a51a1d276911fe19096ad90144e9fe (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 arch/arm/kvm, 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 | 5 | ||||
| -rw-r--r-- | arch/arm/kvm/psci.c | 4 | ||||
| -rw-r--r-- | arch/arm64/include/asm/kvm_host.h | 4 |
3 files changed, 13 insertions, 0 deletions
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 2fda7e905754..82c71a147f21 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -349,4 +349,9 @@ static inline int kvm_arm_have_ssbd(void) return KVM_SSBD_UNKNOWN; } +static inline bool kvm_arm_spectre_bhb_mitigated(void) +{ + /* 32bit guests don't need firmware for this */ + return false; +} #endif /* __ARM_KVM_HOST_H__ */ diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c index 83365bec04b6..a262c175456d 100644 --- a/arch/arm/kvm/psci.c +++ b/arch/arm/kvm/psci.c @@ -431,6 +431,10 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) break; } break; + case ARM_SMCCC_ARCH_WORKAROUND_3: + if (kvm_arm_spectre_bhb_mitigated()) + val = SMCCC_RET_SUCCESS; + break; } break; default: diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index a152a7bbc85a..a75f02e5f0fd 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -452,4 +452,8 @@ static inline int kvm_arm_have_ssbd(void) } } +static inline bool kvm_arm_spectre_bhb_mitigated(void) +{ + return arm64_get_spectre_bhb_state() == SPECTRE_MITIGATED; +} #endif /* __ARM64_KVM_HOST_H__ */ |