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| author | Sean Christopherson <seanjc@google.com> | 2024-08-02 20:19:28 +0200 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2024-08-22 21:06:29 +0200 |
| commit | aaecae7b6a2b19a874a7df0d474f44f3a5b5a74e (patch) | |
| tree | 6e82f5642631f571718ad9725a639761e656c963 /arch/x86/kvm/x86.h | |
| parent | KVM: x86: Move MSR_TYPE_{R,W,RW} values from VMX to x86, as enums (diff) | |
| download | linux-aaecae7b6a2b19a874a7df0d474f44f3a5b5a74e.tar.xz linux-aaecae7b6a2b19a874a7df0d474f44f3a5b5a74e.zip | |
KVM: x86: Rename KVM_MSR_RET_INVALID to KVM_MSR_RET_UNSUPPORTED
Rename the "INVALID" internal MSR error return code to "UNSUPPORTED" to
try and make it more clear that access was denied because the MSR itself
is unsupported/unknown. "INVALID" is too ambiguous, as it could just as
easily mean the value for WRMSR as invalid.
Avoid UNKNOWN and UNIMPLEMENTED, as the error code is used for MSRs that
_are_ actually implemented by KVM, e.g. if the MSR is unsupported because
an associated feature flag is not present in guest CPUID.
Opportunistically beef up the comments for the internal MSR error codes.
Link: https://lore.kernel.org/r/20240802181935.292540-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Diffstat (limited to '')
| -rw-r--r-- | arch/x86/kvm/x86.h | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h index 499adef96038..f47b9905ba78 100644 --- a/arch/x86/kvm/x86.h +++ b/arch/x86/kvm/x86.h @@ -512,11 +512,18 @@ enum kvm_msr_access { /* * Internal error codes that are used to indicate that MSR emulation encountered - * an error that should result in #GP in the guest, unless userspace - * handles it. + * an error that should result in #GP in the guest, unless userspace handles it. + * Note, '1', '0', and negative numbers are off limits, as they are used by KVM + * as part of KVM's lightly documented internal KVM_RUN return codes. + * + * UNSUPPORTED - The MSR isn't supported, either because it is completely + * unknown to KVM, or because the MSR should not exist according + * to the vCPU model. + * + * FILTERED - Access to the MSR is denied by a userspace MSR filter. */ -#define KVM_MSR_RET_INVALID 2 /* in-kernel MSR emulation #GP condition */ -#define KVM_MSR_RET_FILTERED 3 /* #GP due to userspace MSR filter */ +#define KVM_MSR_RET_UNSUPPORTED 2 +#define KVM_MSR_RET_FILTERED 3 #define __cr4_reserved_bits(__cpu_has, __c) \ ({ \ |