diff options
| author | Paolo Bonzini <pbonzini@redhat.com> | 2016-11-01 00:39:48 +0100 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2016-11-02 20:03:07 +0100 |
| commit | ea26e4ec08d4727e3a9e48a6b74695861effcbd9 (patch) | |
| tree | be3ae8868bd0e93e6029cfd9ce0512fe69dc39ab /arch/x86/kvm/x86.c | |
| parent | bd768e146624cbec7122ed15dead8daa137d909d (diff) | |
KVM: x86: drop TSC offsetting kvm_x86_ops to fix KVM_GET/SET_CLOCK
Since commit a545ab6a0085 ("kvm: x86: add tsc_offset field to struct
kvm_vcpu_arch", 2016-09-07) the offset between host and L1 TSC is
cached and need not be fished out of the VMCS or VMCB. This means
that we can implement adjust_tsc_offset_guest and read_l1_tsc
entirely in generic code. The simplification is particularly
significant for VMX code, where vmx->nested.vmcs01_tsc_offset
was duplicating what is now in vcpu->arch.tsc_offset. Therefore
the vmcs01_tsc_offset can be dropped completely.
More importantly, this fixes KVM_GET_CLOCK/KVM_SET_CLOCK
which, after commit 108b249c453d ("KVM: x86: introduce get_kvmclock_ns",
2016-09-01) called read_l1_tsc while the VMCS was not loaded.
It thus returned bogus values on Intel CPUs.
Fixes: 108b249c453dd7132599ab6dc7e435a7036c193f
Reported-by: Roman Kagan <rkagan@virtuozzo.com>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/x86.c')
| -rw-r--r-- | arch/x86/kvm/x86.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index e954be8a3185..3017de0431bd 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1409,7 +1409,7 @@ static u64 kvm_compute_tsc_offset(struct kvm_vcpu *vcpu, u64 target_tsc) u64 kvm_read_l1_tsc(struct kvm_vcpu *vcpu, u64 host_tsc) { - return kvm_x86_ops->read_l1_tsc(vcpu, kvm_scale_tsc(vcpu, host_tsc)); + return vcpu->arch.tsc_offset + kvm_scale_tsc(vcpu, host_tsc); } EXPORT_SYMBOL_GPL(kvm_read_l1_tsc); @@ -1547,7 +1547,7 @@ EXPORT_SYMBOL_GPL(kvm_write_tsc); static inline void adjust_tsc_offset_guest(struct kvm_vcpu *vcpu, s64 adjustment) { - kvm_x86_ops->adjust_tsc_offset_guest(vcpu, adjustment); + kvm_vcpu_write_tsc_offset(vcpu, vcpu->arch.tsc_offset + adjustment); } static inline void adjust_tsc_offset_host(struct kvm_vcpu *vcpu, s64 adjustment) @@ -1555,7 +1555,7 @@ static inline void adjust_tsc_offset_host(struct kvm_vcpu *vcpu, s64 adjustment) if (vcpu->arch.tsc_scaling_ratio != kvm_default_tsc_scaling_ratio) WARN_ON(adjustment < 0); adjustment = kvm_scale_tsc(vcpu, (u64) adjustment); - kvm_x86_ops->adjust_tsc_offset_guest(vcpu, adjustment); + adjust_tsc_offset_guest(vcpu, adjustment); } #ifdef CONFIG_X86_64 |