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| author | Sean Christopherson <sean.j.christopherson@intel.com> | 2020-09-30 07:16:56 +0300 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2020-10-22 00:48:49 +0300 |
| commit | c44d9b34701dc19792339ae3764ac7b763cb175c (patch) | |
| tree | d8780878b22c625b076e3bf02ad1e6440ccdf6f0 /arch/x86 | |
| parent | 6e1d849fa3296526e64b75fa227b6377cd0fd3da (diff) | |
| download | linux-c44d9b34701dc19792339ae3764ac7b763cb175c.tar.xz | |
KVM: x86: Invoke vendor's vcpu_after_set_cpuid() after all common updates
Move the call to kvm_x86_ops.vcpu_after_set_cpuid() to the very end of
kvm_vcpu_after_set_cpuid() to allow the vendor implementation to react
to changes made by the common code. In the near future, this will be
used by VMX to update its CR4 guest/host masks to account for reserved
bits. In the long term, SGX support will update the allowed XCR0 mask
for enclaves based on the vCPU's allowed XCR0.
vcpu_after_set_cpuid() (nee kvm_update_cpuid()) was originally added by
commit 2acf923e38fb ("KVM: VMX: Enable XSAVE/XRSTOR for guest"), and was
called separately after kvm_x86_ops.vcpu_after_set_cpuid() (nee
kvm_x86_ops->cpuid_update()). There is no indication that the placement
of the common code updates after the vendor updates was anything more
than a "new function at the end" decision.
Inspection of the current code reveals no dependency on kvm_x86_ops'
vcpu_after_set_cpuid() in kvm_vcpu_after_set_cpuid() or any of its
helpers. The bulk of the common code depends only on the guest's CPUID
configuration, kvm_mmu_reset_context() does not consume dynamic vendor
state, and there are no collisions between kvm_pmu_refresh() and VMX's
update of PT state.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200930041659.28181-3-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kvm/cpuid.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 5a62fa4ee493..35223eb63242 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -145,8 +145,6 @@ static void kvm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) struct kvm_lapic *apic = vcpu->arch.apic; struct kvm_cpuid_entry2 *best; - kvm_x86_ops.vcpu_after_set_cpuid(vcpu); - best = kvm_find_cpuid_entry(vcpu, 1, 0); if (best && apic) { if (cpuid_entry_has(best, X86_FEATURE_TSC_DEADLINE_TIMER)) @@ -170,6 +168,9 @@ static void kvm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) kvm_pmu_refresh(vcpu); vcpu->arch.cr4_guest_rsvd_bits = __cr4_reserved_bits(guest_cpuid_has, vcpu); + + /* Invoke the vendor callback only after the above state is updated. */ + kvm_x86_ops.vcpu_after_set_cpuid(vcpu); kvm_x86_ops.update_exception_bitmap(vcpu); } |