From c118bbb52743df70e6297671606c1c08edc659fe Mon Sep 17 00:00:00 2001 From: Andre Przywara Date: Fri, 3 May 2019 15:27:48 +0100 Subject: 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 Reviewed-by: Steven Price Signed-off-by: Marc Zyngier --- virt/kvm/arm/psci.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'virt/kvm') 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()) { -- cgit v1.2.3-55-g7522