On Wed, 2022-04-27 at 13:37 -0400, Paolo Bonzini wrote:
Right now, the VMX preemption timer is special cased via the hv_timer_pending, but the purpose of the callback can be easily extended to observing any event that can occur only in non-root mode. Interrupts, NMIs etc. are already handled properly by the *_interrupt_allowed callbacks, so what is missing is only MTF. Check it in the newly-renamed callback, so that kvm_vcpu_running's call to kvm_check_nested_events becomes redundant.
Cc: stable@vger.kernel.org Reported-by: Maxim Levitsky mlevitsk@redhat.com Signed-off-by: Paolo Bonzini pbonzini@redhat.com
arch/x86/include/asm/kvm_host.h | 2 +- arch/x86/kvm/vmx/nested.c | 7 ++++++- arch/x86/kvm/x86.c | 8 ++++---- 3 files changed, 11 insertions(+), 6 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 4ff36610af6a..e2e4f60159e9 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1504,7 +1504,7 @@ struct kvm_x86_ops { struct kvm_x86_nested_ops { void (*leave_nested)(struct kvm_vcpu *vcpu); int (*check_events)(struct kvm_vcpu *vcpu);
- bool (*hv_timer_pending)(struct kvm_vcpu *vcpu);
- bool (*has_events)(struct kvm_vcpu *vcpu); void (*triple_fault)(struct kvm_vcpu *vcpu); int (*get_state)(struct kvm_vcpu *vcpu, struct kvm_nested_state __user *user_kvm_nested_state,
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 856c87563883..54672025c3a1 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -3857,6 +3857,11 @@ static bool nested_vmx_preemption_timer_pending(struct kvm_vcpu *vcpu) to_vmx(vcpu)->nested.preemption_timer_expired; } +static bool vmx_has_nested_events(struct kvm_vcpu *vcpu) +{
Typo: needs struct vcpu_vmx *vmx = to_vmx(vcpu);
- return nested_vmx_preemption_timer_pending(vcpu) || vmx->nested.mtf_pending;
+}
static int vmx_check_nested_events(struct kvm_vcpu *vcpu) { struct vcpu_vmx *vmx = to_vmx(vcpu); @@ -6809,7 +6814,7 @@ __init int nested_vmx_hardware_setup(int (*exit_handlers[])(struct kvm_vcpu *)) struct kvm_x86_nested_ops vmx_nested_ops = { .leave_nested = vmx_leave_nested, .check_events = vmx_check_nested_events,
- .hv_timer_pending = nested_vmx_preemption_timer_pending,
- .has_events = vmx_has_nested_events, .triple_fault = nested_vmx_triple_fault, .get_state = vmx_get_nested_state, .set_state = vmx_set_nested_state,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index a6ab19afc638..0e73607b02bd 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -9471,8 +9471,8 @@ static int inject_pending_event(struct kvm_vcpu *vcpu, bool *req_immediate_exit) } if (is_guest_mode(vcpu) &&
kvm_x86_ops.nested_ops->hv_timer_pending &&
kvm_x86_ops.nested_ops->hv_timer_pending(vcpu))
kvm_x86_ops.nested_ops->has_events &&
*req_immediate_exit = true;kvm_x86_ops.nested_ops->has_events(vcpu))
WARN_ON(vcpu->arch.exception.pending); @@ -12183,8 +12183,8 @@ static inline bool kvm_vcpu_has_events(struct kvm_vcpu *vcpu) return true; if (is_guest_mode(vcpu) &&
kvm_x86_ops.nested_ops->hv_timer_pending &&
kvm_x86_ops.nested_ops->hv_timer_pending(vcpu))
kvm_x86_ops.nested_ops->has_events &&
kvm_x86_ops.nested_ops->has_events(vcpu))
Nitpick: Won't it make sense to use conditional static call here instead?
return true;
return false;
Besides nitpicks,
Reviewed-by: Maxim Levitsky mlevitsk@redhat.com
Wasn't able to test on my intel laptop, I am getting out of sudden in qemu:
'cpuid_data is full, no space for cpuid(eax:0x8000001d,ecx:0x3e)'
I will investigate tomorrow.
Best regards, Maxim Levitsky