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| author | Andre Przywara <andre.przywara@arm.com> | 2019-05-03 15:27:48 +0100 |
|---|---|---|
| committer | Marc Zyngier <marc.zyngier@arm.com> | 2019-07-05 13:56:27 +0100 |
| commit | c118bbb52743df70e6297671606c1c08edc659fe (patch) | |
| tree | 3058edcfc6f08fa7b68f9e5ff037c9dc219255a6 /virt | |
| parent | 80f393a23be68e2f8a0f74258d6155438c200bbd (diff) | |
| download | lwn-c118bbb52743df70e6297671606c1c08edc659fe.tar.gz lwn-c118bbb52743df70e6297671606c1c08edc659fe.zip | |
arm64: KVM: Propagate full Spectre v2 workaround state to KVM guests
Recent commits added the explicit notion of "workaround not required" to
the state of the Spectre v2 (aka. BP_HARDENING) workaround, where we
just had "needed" and "unknown" before.
Export this knowledge to the rest of the kernel and enhance the existing
kvm_arm_harden_branch_predictor() to report this new state as well.
Export this new state to guests when they use KVM's firmware interface
emulation.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'virt')
| -rw-r--r-- | virt/kvm/arm/psci.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/virt/kvm/arm/psci.c b/virt/kvm/arm/psci.c index be3c9cdca9f3..355b9e38a42d 100644 --- a/virt/kvm/arm/psci.c +++ b/virt/kvm/arm/psci.c @@ -401,8 +401,16 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) feature = smccc_get_arg1(vcpu); switch(feature) { case ARM_SMCCC_ARCH_WORKAROUND_1: - if (kvm_arm_harden_branch_predictor()) + switch (kvm_arm_harden_branch_predictor()) { + case KVM_BP_HARDEN_UNKNOWN: + break; + case KVM_BP_HARDEN_WA_NEEDED: val = SMCCC_RET_SUCCESS; + break; + case KVM_BP_HARDEN_NOT_REQUIRED: + val = SMCCC_RET_NOT_REQUIRED; + break; + } break; case ARM_SMCCC_ARCH_WORKAROUND_2: switch (kvm_arm_have_ssbd()) { |