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| author | Marc Zyngier <marc.zyngier@arm.com> | 2018-01-21 16:42:56 +0000 |
|---|---|---|
| committer | Marc Zyngier <marc.zyngier@arm.com> | 2018-04-20 16:32:23 +0100 |
| commit | 85bd0ba1ff9875798fad94218b627ea9f768f3c3 (patch) | |
| tree | 7a1d8741a980a8d8d0a235c1784b2121634a9265 /include/kvm | |
| parent | bf9a41377d14f565764022470e14aae72559589a (diff) | |
| download | linux-85bd0ba1ff9875798fad94218b627ea9f768f3c3.tar.bz2 | |
arm/arm64: KVM: Add PSCI version selection API
Although we've implemented PSCI 0.1, 0.2 and 1.0, we expose either 0.1
or 1.0 to a guest, defaulting to the latest version of the PSCI
implementation that is compatible with the requested version. This is
no different from doing a firmware upgrade on KVM.
But in order to give a chance to hypothetical badly implemented guests
that would have a fit by discovering something other than PSCI 0.2,
let's provide a new API that allows userspace to pick one particular
version of the API.
This is implemented as a new class of "firmware" registers, where
we expose the PSCI version. This allows the PSCI version to be
save/restored as part of a guest migration, and also set to
any supported version if the guest requires it.
Cc: stable@vger.kernel.org #4.16
Reviewed-by: Christoffer Dall <cdall@kernel.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'include/kvm')
| -rw-r--r-- | include/kvm/arm_psci.h | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/include/kvm/arm_psci.h b/include/kvm/arm_psci.h index e518e4e3dfb5..4b1548129fa2 100644 --- a/include/kvm/arm_psci.h +++ b/include/kvm/arm_psci.h @@ -37,10 +37,15 @@ static inline int kvm_psci_version(struct kvm_vcpu *vcpu, struct kvm *kvm) * Our PSCI implementation stays the same across versions from * v0.2 onward, only adding the few mandatory functions (such * as FEATURES with 1.0) that are required by newer - * revisions. It is thus safe to return the latest. + * revisions. It is thus safe to return the latest, unless + * userspace has instructed us otherwise. */ - if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features)) + if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features)) { + if (vcpu->kvm->arch.psci_version) + return vcpu->kvm->arch.psci_version; + return KVM_ARM_PSCI_LATEST; + } return KVM_ARM_PSCI_0_1; } @@ -48,4 +53,11 @@ static inline int kvm_psci_version(struct kvm_vcpu *vcpu, struct kvm *kvm) int kvm_hvc_call_handler(struct kvm_vcpu *vcpu); +struct kvm_one_reg; + +int kvm_arm_get_fw_num_regs(struct kvm_vcpu *vcpu); +int kvm_arm_copy_fw_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices); +int kvm_arm_get_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg); +int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg); + #endif /* __KVM_ARM_PSCI_H__ */ |