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| author | Marc Zyngier <marc.zyngier@arm.com> | 2018-02-06 17:56:14 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-02-16 20:22:55 +0100 |
| commit | e47273d086236d06c3c2851fa8599971086b2a73 (patch) | |
| tree | b20bfdb1d9399b6a69700089c2b99acbc5134cce /virt | |
| parent | 2cfe8929f6247dbee8def7e94f334909fe5ac084 (diff) | |
| download | linux-stable-e47273d086236d06c3c2851fa8599971086b2a73.tar.gz linux-stable-e47273d086236d06c3c2851fa8599971086b2a73.tar.bz2 linux-stable-e47273d086236d06c3c2851fa8599971086b2a73.zip | |
arm64: KVM: Report SMCCC_ARCH_WORKAROUND_1 BP hardening support
Commit 6167ec5c9145 upstream.
A new feature of SMCCC 1.1 is that it offers firmware-based CPU
workarounds. In particular, SMCCC_ARCH_WORKAROUND_1 provides
BP hardening for CVE-2017-5715.
If the host has some mitigation for this issue, report that
we deal with it using SMCCC_ARCH_WORKAROUND_1, as we apply the
host workaround on every guest exit.
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'virt')
| -rw-r--r-- | virt/kvm/arm/psci.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/virt/kvm/arm/psci.c b/virt/kvm/arm/psci.c index e105c1153794..6919352cbf15 100644 --- a/virt/kvm/arm/psci.c +++ b/virt/kvm/arm/psci.c @@ -405,13 +405,20 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) { u32 func_id = smccc_get_function(vcpu); u32 val = PSCI_RET_NOT_SUPPORTED; + u32 feature; switch (func_id) { case ARM_SMCCC_VERSION_FUNC_ID: val = ARM_SMCCC_VERSION_1_1; break; case ARM_SMCCC_ARCH_FEATURES_FUNC_ID: - /* Nothing supported yet */ + feature = smccc_get_arg1(vcpu); + switch(feature) { + case ARM_SMCCC_ARCH_WORKAROUND_1: + if (kvm_arm_harden_branch_predictor()) + val = 0; + break; + } break; default: return kvm_psci_call(vcpu); |