* [PATCH] KVM: x86: Fix immediate_exit handling for uninitialized AP
@ 2017-09-06 16:34 Jan H. Schönherr
2017-09-13 15:33 ` Radim Krčmář
0 siblings, 1 reply; 2+ messages in thread
From: Jan H. Schönherr @ 2017-09-06 16:34 UTC (permalink / raw)
To: Paolo Bonzini, Radim Krčmář
Cc: Jan H. Schönherr, David Hildenbrand, kvm
When user space sets kvm_run->immediate_exit, KVM is supposed to
return quickly. However, when a vCPU is in KVM_MP_STATE_UNINITIALIZED,
the value is not considered and the vCPU blocks.
Fix that oversight.
Fixes: 460df4c1fc7c008 ("KVM: race-free exit from KVM_RUN without POSIX signals")
Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
---
compile-time tested only
---
arch/x86/kvm/x86.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 40039cd..a69a948 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -7199,6 +7199,10 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
if (unlikely(vcpu->arch.mp_state == KVM_MP_STATE_UNINITIALIZED)) {
+ if (kvm_run->immediate_exit) {
+ r = -EINTR;
+ goto out;
+ }
kvm_vcpu_block(vcpu);
kvm_apic_accept_events(vcpu);
kvm_clear_request(KVM_REQ_UNHALT, vcpu);
--
2.3.1.dirty
^ permalink raw reply related [flat|nested] 2+ messages in thread* Re: [PATCH] KVM: x86: Fix immediate_exit handling for uninitialized AP
2017-09-06 16:34 [PATCH] KVM: x86: Fix immediate_exit handling for uninitialized AP Jan H. Schönherr
@ 2017-09-13 15:33 ` Radim Krčmář
0 siblings, 0 replies; 2+ messages in thread
From: Radim Krčmář @ 2017-09-13 15:33 UTC (permalink / raw)
To: Jan H. Schönherr; +Cc: Paolo Bonzini, David Hildenbrand, kvm
2017-09-06 18:34+0200, Jan H. Schönherr:
> When user space sets kvm_run->immediate_exit, KVM is supposed to
> return quickly. However, when a vCPU is in KVM_MP_STATE_UNINITIALIZED,
> the value is not considered and the vCPU blocks.
>
> Fix that oversight.
>
> Fixes: 460df4c1fc7c008 ("KVM: race-free exit from KVM_RUN without POSIX signals")
> Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
> ---
> compile-time tested only
> ---
> arch/x86/kvm/x86.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 40039cd..a69a948 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -7199,6 +7199,10 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
> sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
>
> if (unlikely(vcpu->arch.mp_state == KVM_MP_STATE_UNINITIALIZED)) {
> + if (kvm_run->immediate_exit) {
> + r = -EINTR;
> + goto out;
> + }
> kvm_vcpu_block(vcpu);
Without immediate_exit, we would also execute the following code, but I
think it's ok not to ... queued, thanks.
> kvm_apic_accept_events(vcpu);
> kvm_clear_request(KVM_REQ_UNHALT, vcpu);
> --
> 2.3.1.dirty
>
^ permalink raw reply [flat|nested] 2+ messages in thread
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2017-09-13 15:33 ` Radim Krčmář
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