From: Paolo Bonzini <pbonzini@redhat.com>
To: Wanpeng Li <kernellwp@gmail.com>,
linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: "Radim Krčmář" <rkrcmar@redhat.com>,
"Wanpeng Li" <wanpeng.li@hotmail.com>
Subject: Re: [PATCH v2] KVM: X86: Fix loss of pending INIT due to race
Date: Wed, 2 Aug 2017 09:44:27 +0200 [thread overview]
Message-ID: <117b7114-eeb0-2074-f287-ed5bafae18a2@redhat.com> (raw)
In-Reply-To: <1501628725-3381-1-git-send-email-wanpeng.li@hotmail.com>
On 02/08/2017 01:05, Wanpeng Li wrote:
> From: Wanpeng Li <wanpeng.li@hotmail.com>
>
> When SMP VM start, AP may lost INIT because of receiving INIT between
> kvm_vcpu_ioctl_x86_get/set_vcpu_events.
>
> vcpu 0 vcpu 1
> kvm_vcpu_ioctl_x86_get_vcpu_events
> events->smi.latched_init = 0
> send INIT to vcpu1
> set vcpu1's pending_events
> kvm_vcpu_ioctl_x86_set_vcpu_events
> if (events->smi.latched_init == 0)
> clear INIT in pending_events
>
> This patch fixes it by just update SMM related flags if we are in SMM.
>
> Thanks Peng Hao for the report and original commit message.
>
> Reported-by: Peng Hao <peng.hao2@zte.com.cn>
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Cc: Radim Krčmář <rkrcmar@redhat.com>
> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
> ---
> v1 -> v2:
> * move the stuff under if (events->smi_smm)
>
> arch/x86/kvm/x86.c | 19 +++++++++++--------
> 1 file changed, 11 insertions(+), 8 deletions(-)
>
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 1a4c84d..839b5dad6 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -3160,15 +3160,18 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu,
> kvm_set_hflags(vcpu, hflags);
>
> vcpu->arch.smi_pending = events->smi.pending;
> - if (events->smi.smm_inside_nmi)
> - vcpu->arch.hflags |= HF_SMM_INSIDE_NMI_MASK;
> - else
> - vcpu->arch.hflags &= ~HF_SMM_INSIDE_NMI_MASK;
> - if (lapic_in_kernel(vcpu)) {
> - if (events->smi.latched_init)
> - set_bit(KVM_APIC_INIT, &vcpu->arch.apic->pending_events);
> +
> + if (events->smi.smm) {
> + if (events->smi.smm_inside_nmi)
> + vcpu->arch.hflags |= HF_SMM_INSIDE_NMI_MASK;
> else
> - clear_bit(KVM_APIC_INIT, &vcpu->arch.apic->pending_events);
> + vcpu->arch.hflags &= ~HF_SMM_INSIDE_NMI_MASK;
> + if (lapic_in_kernel(vcpu)) {
> + if (events->smi.latched_init)
> + set_bit(KVM_APIC_INIT, &vcpu->arch.apic->pending_events);
> + else
> + clear_bit(KVM_APIC_INIT, &vcpu->arch.apic->pending_events);
> + }
> }
> }
>
>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
prev parent reply other threads:[~2017-08-02 7:44 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-08-01 23:05 [PATCH v2] KVM: X86: Fix loss of pending INIT due to race Wanpeng Li
2017-08-02 7:44 ` Paolo Bonzini [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=117b7114-eeb0-2074-f287-ed5bafae18a2@redhat.com \
--to=pbonzini@redhat.com \
--cc=kernellwp@gmail.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=rkrcmar@redhat.com \
--cc=wanpeng.li@hotmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.