| Message ID | 5459DA93.6060104@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 05/11/2014 4:07, Tiejun Chen wrote: > >>> A bug was reported as follows: when running Windows 7 32-bit guests > >>> on qemu-kvm, sometimes the guests run into blue screen during > >>> reboot. The problem was that a guest's RVI was not cleared when it > >>> rebooted. This > >> patch has fixed the problem. > >>> > >>> Signed-off-by: Wei Wang <wei.w.wang@intel.com> > >>> Signed-off-by: Yang Zhang <yang.z.zhang@intel.com> > >>> Tested-by: Rongrong Liu <rongrongx.liu@intel.com>, Da Chun > >>> <ngugc@qq.com> > >>> --- > >>> arch/x86/kvm/lapic.c | 3 +++ > >>> arch/x86/kvm/vmx.c | 12 ++++++------ > >>> 2 files changed, 9 insertions(+), 6 deletions(-) > >>> > >>> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index > >>> 66dd173..6942742 100644 > >>> --- a/arch/x86/kvm/lapic.c > >>> +++ b/arch/x86/kvm/lapic.c > >>> @@ -1712,6 +1712,9 @@ void kvm_apic_post_state_restore(struct > >> kvm_vcpu *vcpu, > >>> apic->isr_count = kvm_apic_vid_enabled(vcpu->kvm) ? > >>> 1 : count_vectors(apic->regs + APIC_ISR); > >>> apic->highest_isr_cache = -1; > >>> + if (kvm_x86_ops->hwapic_irr_update) > >>> + kvm_x86_ops->hwapic_irr_update(vcpu, > >>> + apic_find_highest_irr(apic)); > >> > >> Could we pass 0 directly? Because looks we just need to clear RVI. > >> > >> kvm_x86_ops->hwapic_irr_update(vcpu, 0); > >> > >> I think this already makes sense based on your description. > >> > >> Thanks > >> Tiejun > > > > No. This is a restore function, and we cannot assume that the callers > always need to reset to the initial state. > > Okay. Maybe I'm confused by the following change. > > > > > Wei > >> > >>> kvm_x86_ops->hwapic_isr_update(vcpu->kvm, > >> apic_find_highest_isr(apic)); > >>> kvm_make_request(KVM_REQ_EVENT, vcpu); > >>> kvm_rtc_eoi_tracking_restore_one(vcpu); > >>> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index > >>> fe4d2f4..d632548 100644 > >>> --- a/arch/x86/kvm/vmx.c > >>> +++ b/arch/x86/kvm/vmx.c > >>> @@ -7292,19 +7292,19 @@ static void vmx_set_rvi(int vector) > >>> static void vmx_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr) > >>> { > >>> if (max_irr == -1) > >>> + max_irr = 0; > >>> + > >>> + if (!is_guest_mode(vcpu)) { > >>> + vmx_set_rvi(max_irr); > >>> return; > >>> + } > >>> > >>> /* > >>> * If a vmexit is needed, vmx_check_nested_events handles it. > >>> */ > >>> - if (is_guest_mode(vcpu) && nested_exit_on_intr(vcpu)) > >>> + if ((is_guest_mode(vcpu) && nested_exit_on_intr(vcpu)) || max_irr > >> == > >>> +0) > > Its really not readable to modify max_irr as 0 and check that here, and > especially when you read the original comment. > > So what about this? I think both are ok. If we zero max_irr in vmx_set_rvi(), we still need this check: if ((is_guest_mode(vcpu) && nested_exit_on_intr(vcpu)) || max_irr == -1) Let's see if Paolo has any comments, then send out a second version. Wei > > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index > 0cd99d8..bc4558b 100644 > --- a/arch/x86/kvm/vmx.c > +++ b/arch/x86/kvm/vmx.c > @@ -7280,6 +7280,9 @@ static void vmx_set_rvi(int vector) > u16 status; > u8 old; > > + if (vector == -1) > + vector = 0; > + > status = vmcs_read16(GUEST_INTR_STATUS); > old = (u8)status & 0xff; > if ((u8)vector != old) { > @@ -7291,9 +7294,6 @@ static void vmx_set_rvi(int vector) > > static void vmx_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr) > { > - if (max_irr == -1) > - return; > - > /* > * If a vmexit is needed, vmx_check_nested_events handles it. > */ > @@ -7305,6 +7305,9 @@ static void vmx_hwapic_irr_update(struct > kvm_vcpu *vcpu, int max_irr) > return; > } > > + if (max_irr == -1) > + return; > + > /* > * Fall back to pre-APICv interrupt injection since L2 > * is run without virtual interrupt delivery. > > > Thanks > Tiejun > > >>> return; > >>> > >>> - if (!is_guest_mode(vcpu)) { > >>> - vmx_set_rvi(max_irr); > >>> - return; > >>> - } > >>> - > >>> /* > >>> * Fall back to pre-APICv interrupt injection since L2 > >>> * is run without virtual interrupt delivery. > >>> > > > > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 2014/11/5 16:50, Wang, Wei W wrote: > On 05/11/2014 4:07, Tiejun Chen wrote: >>>>> A bug was reported as follows: when running Windows 7 32-bit guests >>>>> on qemu-kvm, sometimes the guests run into blue screen during >>>>> reboot. The problem was that a guest's RVI was not cleared when it >>>>> rebooted. This >>>> patch has fixed the problem. >>>>> >>>>> Signed-off-by: Wei Wang <wei.w.wang@intel.com> >>>>> Signed-off-by: Yang Zhang <yang.z.zhang@intel.com> >>>>> Tested-by: Rongrong Liu <rongrongx.liu@intel.com>, Da Chun >>>>> <ngugc@qq.com> >>>>> --- >>>>> arch/x86/kvm/lapic.c | 3 +++ >>>>> arch/x86/kvm/vmx.c | 12 ++++++------ >>>>> 2 files changed, 9 insertions(+), 6 deletions(-) >>>>> >>>>> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index >>>>> 66dd173..6942742 100644 >>>>> --- a/arch/x86/kvm/lapic.c >>>>> +++ b/arch/x86/kvm/lapic.c >>>>> @@ -1712,6 +1712,9 @@ void kvm_apic_post_state_restore(struct >>>> kvm_vcpu *vcpu, >>>>> apic->isr_count = kvm_apic_vid_enabled(vcpu->kvm) ? >>>>> 1 : count_vectors(apic->regs + APIC_ISR); >>>>> apic->highest_isr_cache = -1; >>>>> + if (kvm_x86_ops->hwapic_irr_update) >>>>> + kvm_x86_ops->hwapic_irr_update(vcpu, >>>>> + apic_find_highest_irr(apic)); >>>> >>>> Could we pass 0 directly? Because looks we just need to clear RVI. >>>> >>>> kvm_x86_ops->hwapic_irr_update(vcpu, 0); >>>> >>>> I think this already makes sense based on your description. >>>> >>>> Thanks >>>> Tiejun >>> >>> No. This is a restore function, and we cannot assume that the callers >> always need to reset to the initial state. >> >> Okay. Maybe I'm confused by the following change. >> >>> >>> Wei >>>> >>>>> kvm_x86_ops->hwapic_isr_update(vcpu->kvm, >>>> apic_find_highest_isr(apic)); >>>>> kvm_make_request(KVM_REQ_EVENT, vcpu); >>>>> kvm_rtc_eoi_tracking_restore_one(vcpu); >>>>> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index >>>>> fe4d2f4..d632548 100644 >>>>> --- a/arch/x86/kvm/vmx.c >>>>> +++ b/arch/x86/kvm/vmx.c >>>>> @@ -7292,19 +7292,19 @@ static void vmx_set_rvi(int vector) >>>>> static void vmx_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr) >>>>> { >>>>> if (max_irr == -1) >>>>> + max_irr = 0; >>>>> + >>>>> + if (!is_guest_mode(vcpu)) { >>>>> + vmx_set_rvi(max_irr); >>>>> return; >>>>> + } >>>>> >>>>> /* >>>>> * If a vmexit is needed, vmx_check_nested_events handles it. >>>>> */ >>>>> - if (is_guest_mode(vcpu) && nested_exit_on_intr(vcpu)) >>>>> + if ((is_guest_mode(vcpu) && nested_exit_on_intr(vcpu)) || max_irr >>>> == >>>>> +0) >> >> Its really not readable to modify max_irr as 0 and check that here, and >> especially when you read the original comment. >> >> So what about this? > > > I think both are ok. > If we zero max_irr in vmx_set_rvi(), we still need this check: > if ((is_guest_mode(vcpu) && nested_exit_on_intr(vcpu)) || max_irr == -1) No, I don't think we need to add this. > > Let's see if Paolo has any comments, then send out a second version. > > Wei >> >> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index >> 0cd99d8..bc4558b 100644 >> --- a/arch/x86/kvm/vmx.c >> +++ b/arch/x86/kvm/vmx.c >> @@ -7280,6 +7280,9 @@ static void vmx_set_rvi(int vector) >> u16 status; >> u8 old; >> >> + if (vector == -1) >> + vector = 0; >> + >> status = vmcs_read16(GUEST_INTR_STATUS); >> old = (u8)status & 0xff; >> if ((u8)vector != old) { >> @@ -7291,9 +7294,6 @@ static void vmx_set_rvi(int vector) >> >> static void vmx_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr) >> { >> - if (max_irr == -1) >> - return; >> - >> /* >> * If a vmexit is needed, vmx_check_nested_events handles it. >> */ >> @@ -7305,6 +7305,9 @@ static void vmx_hwapic_irr_update(struct >> kvm_vcpu *vcpu, int max_irr) >> return; >> } >> >> + if (max_irr == -1) >> + return; >> + Did you see this? Tiejun >> /* >> * Fall back to pre-APICv interrupt injection since L2 >> * is run without virtual interrupt delivery. >> >> >> Thanks >> Tiejun >> >>>>> return; >>>>> >>>>> - if (!is_guest_mode(vcpu)) { >>>>> - vmx_set_rvi(max_irr); >>>>> - return; >>>>> - } >>>>> - >>>>> /* >>>>> * Fall back to pre-APICv interrupt injection since L2 >>>>> * is run without virtual interrupt delivery. >>>>> >>> >>> > > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 05/11/2014 10:02, Chen, Tiejun wrote: >> I think both are ok. >> If we zero max_irr in vmx_set_rvi(), we still need this check: >> if ((is_guest_mode(vcpu) && nested_exit_on_intr(vcpu)) || max_irr == -1) > > No, I don't think we need to add this. You don't, because the code will look like: if (is_guest_mode(vcpu) && nested_exit_on_intr(vcpu)) return; if (!is_guest_mode(vcpu)) { vmx_set_rvi(max_irr); return; } if (max_irr == -1) return; and thus vmx_set_rvi() is never reached if is_guest_mode(vcpu) && !nested_exit_on_intr(vcpu). I applied the lapic.c part of Wei's patch, and the vmx.c part of Tiejun's patch. Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Paolo Bonzini wrote on 2014-11-05: > > > On 05/11/2014 10:02, Chen, Tiejun wrote: >>> I think both are ok. >>> If we zero max_irr in vmx_set_rvi(), we still need this check: >>> if ((is_guest_mode(vcpu) && nested_exit_on_intr(vcpu)) || max_irr >>> == >>> -1) >> >> No, I don't think we need to add this. > > You don't, because the code will look like: > > if (is_guest_mode(vcpu) && nested_exit_on_intr(vcpu)) > return; > if (!is_guest_mode(vcpu)) { > vmx_set_rvi(max_irr); > return; > } > > if (max_irr == -1) > return; > and thus vmx_set_rvi() is never reached if is_guest_mode(vcpu) && > !nested_exit_on_intr(vcpu). I don't think the above code is perfect. Since hwapic_irr_update() is a hot point, it's better to move the first check after the second check. In this case, Wei's patch looks more reasonable. > > I applied the lapic.c part of Wei's patch, and the vmx.c part of Tiejun's patch. > > Paolo Best regards, Yang -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Then? >> On 05/11/2014 10:02, Chen, Tiejun wrote: >>>> I think both are ok. >>>> If we zero max_irr in vmx_set_rvi(), we still need this check: >>>> if ((is_guest_mode(vcpu) && nested_exit_on_intr(vcpu)) || max_irr >>>> == >>>> -1) >>> >>> No, I don't think we need to add this. >> >> You don't, because the code will look like: >> >> if (is_guest_mode(vcpu) && nested_exit_on_intr(vcpu)) >> return; >> if (!is_guest_mode(vcpu)) { >> vmx_set_rvi(max_irr); >> return; >> } >> >> if (max_irr == -1) >> return; >> and thus vmx_set_rvi() is never reached if is_guest_mode(vcpu) && >> !nested_exit_on_intr(vcpu). > >I don't think the above code is perfect. Since hwapic_irr_update() is a hot point, it's better to move the first check after the second check. In this case, Wei's patch looks more reasonable. > >> >> I applied the lapic.c part of Wei's patch, and the vmx.c part of Tiejun's patch. >> >> Paolo > > >Best regards, -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Zhang Haoyu wrote on 2014-12-11: > Then? It's already in upstream KVM commit 4114c27d450bef228be9c7b0c40a888e18a3a636 Author: Wei Wang <wei.w.wang@intel.com> Date: Wed Nov 5 10:53:43 2014 +0800 KVM: x86: reset RVI upon system reset A bug was reported as follows: when running Windows 7 32-bit guests on qemu-kvm, sometimes the guests run into blue screen during reboot. The problem was that a guest's RVI was not cleared when it rebooted. This patch has fixed the problem. Signed-off-by: Wei Wang <wei.w.wang@intel.com> Signed-off-by: Yang Zhang <yang.z.zhang@intel.com> Tested-by: Rongrong Liu <rongrongx.liu@intel.com>, Da Chun <ngugc@qq.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> > >>> On 05/11/2014 10:02, Chen, Tiejun wrote: >>>>> I think both are ok. >>>>> If we zero max_irr in vmx_set_rvi(), we still need this check: >>>>> if ((is_guest_mode(vcpu) && nested_exit_on_intr(vcpu)) || max_irr >>>>> == >>>>> -1) >>>> >>>> No, I don't think we need to add this. >>> >>> You don't, because the code will look like: >>> >>> if (is_guest_mode(vcpu) && nested_exit_on_intr(vcpu)) >>> return; if (!is_guest_mode(vcpu)) { >>> vmx_set_rvi(max_irr); return; >>> } >>> >>> if (max_irr == -1) >>> return; >>> and thus vmx_set_rvi() is never reached if is_guest_mode(vcpu) && >>> !nested_exit_on_intr(vcpu). >> >> I don't think the above code is perfect. Since hwapic_irr_update() is >> a hot point, > it's better to move the first check after the second check. In this > case, Wei's patch looks more reasonable. >> >>> >>> I applied the lapic.c part of Wei's patch, and the vmx.c part of Tiejun's patch. >>> >>> Paolo >> >> >> Best regards, Best regards, Yang -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 11/12/2014 09:15, Zhang Haoyu wrote: >> >> if (is_guest_mode(vcpu) && nested_exit_on_intr(vcpu)) >> >> return; >> >> if (!is_guest_mode(vcpu)) { >> >> vmx_set_rvi(max_irr); >> >> return; >> >> } >> >> >> >> if (max_irr == -1) >> >> return; >> >> and thus vmx_set_rvi() is never reached if is_guest_mode(vcpu) && >> >> !nested_exit_on_intr(vcpu). >> >>I don't think the above code is perfect. Since hwapic_irr_update() is a hot point, it's better to move the first check after the second check. In this case, Wei's patch looks more The behavior for max_irr == -1 is different for is_guest_mode(vcpu) (write 0 to RVI) and !is_guest_mode(vcpu) (do nothing). So you have to check is_guest_mode first, as in the patch that was applied. Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 2014-12-11 19:06:33, Zhang, Yang Z wrote: >Zhang Haoyu wrote on 2014-12-11: >> Then? > >It's already in upstream KVM > Strange, I didn't find this commit in https://git.kernel.org/cgit/virt/kvm/kvm.git/log/ but found it from the repository downloaded by git clone git://git.kernel.org/pub/scm/virt/kvm/kvm.git Thanks, Zhang Haoyu >commit 4114c27d450bef228be9c7b0c40a888e18a3a636 >Author: Wei Wang <wei.w.wang@intel.com> >Date: Wed Nov 5 10:53:43 2014 +0800 > > KVM: x86: reset RVI upon system reset > > A bug was reported as follows: when running Windows 7 32-bit guests on qemu-kvm, > sometimes the guests run into blue screen during reboot. The problem was that a > guest's RVI was not cleared when it rebooted. This patch has fixed the problem. > > Signed-off-by: Wei Wang <wei.w.wang@intel.com> > Signed-off-by: Yang Zhang <yang.z.zhang@intel.com> > Tested-by: Rongrong Liu <rongrongx.liu@intel.com>, Da Chun <ngugc@qq.com> > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> > > >> >>>> On 05/11/2014 10:02, Chen, Tiejun wrote: >>>>>> I think both are ok. >>>>>> If we zero max_irr in vmx_set_rvi(), we still need this check: >>>>>> if ((is_guest_mode(vcpu) && nested_exit_on_intr(vcpu)) || max_irr >>>>>> == >>>>>> -1) >>>>> >>>>> No, I don't think we need to add this. >>>> >>>> You don't, because the code will look like: >>>> >>>> if (is_guest_mode(vcpu) && nested_exit_on_intr(vcpu)) >>>> return; if (!is_guest_mode(vcpu)) { >>>> vmx_set_rvi(max_irr); return; >>>> } >>>> >>>> if (max_irr == -1) >>>> return; >>>> and thus vmx_set_rvi() is never reached if is_guest_mode(vcpu) && >>>> !nested_exit_on_intr(vcpu). >>> >>> I don't think the above code is perfect. Since hwapic_irr_update() is >>> a hot point, >> it's better to move the first check after the second check. In this >> case, Wei's patch looks more reasonable. >>> >>>> >>>> I applied the lapic.c part of Wei's patch, and the vmx.c part of Tiejun's patch. >>>> >>>> Paolo >>> >>> >>> Best regards, > > >Best regards, >Yang -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 12/12/2014 10:56, Zhang Haoyu wrote: > Strange, I didn't find this commit in https://git.kernel.org/cgit/virt/kvm/kvm.git/log/ > but found it from the repository downloaded by git clone git://git.kernel.org/pub/scm/virt/kvm/kvm.git It's here: https://git.kernel.org/cgit/virt/kvm/kvm.git/log/?h=next (on the second page) Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 2014-12-12 18:27:14, Paolo Bonzini wrote: > > >On 12/12/2014 10:56, Zhang Haoyu wrote: >> Strange, I didn't find this commit in https://git.kernel.org/cgit/virt/kvm/kvm.git/log/ >> but found it from the repository downloaded by git clone git://git.kernel.org/pub/scm/virt/kvm/kvm.git > >It's here: > >https://git.kernel.org/cgit/virt/kvm/kvm.git/log/?h=next > >(on the second page) > Yes, I find it, but what's the relationship between https://git.kernel.org/cgit/virt/kvm/kvm.git/log/?h=next and https://git.kernel.org/cgit/virt/kvm/kvm.git/log/ ? e.g., https://git.kernel.org/cgit/virt/kvm/kvm.git/log/?h=next&ofs=50 https://git.kernel.org/cgit/virt/kvm/kvm.git/log/?ofs=50 Thanks, Zhang Haoyu >Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 15/12/2014 02:52, Zhang Haoyu wrote: > Yes, I find it, > but what's the relationship between https://git.kernel.org/cgit/virt/kvm/kvm.git/log/?h=next This is branch "next". > and > https://git.kernel.org/cgit/virt/kvm/kvm.git/log/ ? This is branch "master". Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 0cd99d8..bc4558b 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -7280,6 +7280,9 @@ static void vmx_set_rvi(int vector) u16 status; u8 old; + if (vector == -1) + vector = 0; + status = vmcs_read16(GUEST_INTR_STATUS); old = (u8)status & 0xff; if ((u8)vector != old) { @@ -7291,9 +7294,6 @@ static void vmx_set_rvi(int vector) static void vmx_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr) { - if (max_irr == -1) - return; - /* * If a vmexit is needed, vmx_check_nested_events handles it. */ @@ -7305,6 +7305,9 @@ static void vmx_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr) return; } + if (max_irr == -1) + return; + /* * Fall back to pre-APICv interrupt injection since L2