On Thu, 2021-05-06 at 10:32 +0000, ilstam@xxxxxxxxxxx wrote:
> From: Ilias Stamatis <ilstam@xxxxxxxxxx>
>
> Store L1's scaling ratio in that struct like we already do for L1's TSC
> offset. This allows for easy save/restore when we enter and then exit
> the nested guest.
>
> Signed-off-by: Ilias Stamatis <ilstam@xxxxxxxxxx>
> ---
> arch/x86/include/asm/kvm_host.h | 5 +++--
> arch/x86/kvm/x86.c | 4 +++-
> 2 files changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> index cbbcee0a84f9..132e820525fb 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -705,7 +705,7 @@ struct kvm_vcpu_arch {
> } st;
>
> u64 l1_tsc_offset;
> - u64 tsc_offset;
> + u64 tsc_offset; /* current tsc offset */
> u64 last_guest_tsc;
> u64 last_host_tsc;
> u64 tsc_offset_adjustment;
> @@ -719,7 +719,8 @@ struct kvm_vcpu_arch {
> u32 virtual_tsc_khz;
> s64 ia32_tsc_adjust_msr;
> u64 msr_ia32_power_ctl;
> - u64 tsc_scaling_ratio;
> + u64 l1_tsc_scaling_ratio;
> + u64 tsc_scaling_ratio; /* current scaling ratio */
>
> atomic_t nmi_queued; /* unprocessed asynchronous NMIs */
> unsigned nmi_pending; /* NMI queued after currently running handler */
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index cebdaa1e3cf5..7bc5155ac6fd 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -2119,6 +2119,7 @@ static int set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz, bool scale)
>
> /* Guest TSC same frequency as host TSC? */
> if (!scale) {
> + vcpu->arch.l1_tsc_scaling_ratio = kvm_default_tsc_scaling_ratio;
> vcpu->arch.tsc_scaling_ratio = kvm_default_tsc_scaling_ratio;
> return 0;
> }
> @@ -2145,7 +2146,7 @@ static int set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz, bool scale)
> return -1;
> }
>
> - vcpu->arch.tsc_scaling_ratio = ratio;
> + vcpu->arch.l1_tsc_scaling_ratio = vcpu->arch.tsc_scaling_ratio = ratio;
> return 0;
> }
>
> @@ -2157,6 +2158,7 @@ static int kvm_set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz)
> /* tsc_khz can be zero if TSC calibration fails */
> if (user_tsc_khz == 0) {
> /* set tsc_scaling_ratio to a safe value */
> + vcpu->arch.l1_tsc_scaling_ratio = kvm_default_tsc_scaling_ratio;
> vcpu->arch.tsc_scaling_ratio = kvm_default_tsc_scaling_ratio;
> return -1;
> }
Reviewed-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
