RE: [PATCH CFT 0/4] VT-d PI fixes

[Gonglei (Arei)]

> -----Original Message-----
> From: kvm-owner@xxxxxxxxxxxxxxx [mailto:kvm-owner@xxxxxxxxxxxxxxx] On
> Behalf Of Paolo Bonzini
> Sent: Tuesday, July 11, 2017 4:56 PM
> To: Gonglei (Arei)
> Cc: linux-kernel@xxxxxxxxxxxxxxx; kvm@xxxxxxxxxxxxxxx; longpeng;
> Huangweidong (C); wangxin (U); Radim Krčmář
> Subject: Re: [PATCH CFT 0/4] VT-d PI fixes
> 
> On 07/06/2017 11:33, Gonglei (Arei) wrote:
> > We are testing your patch, but maybe need some time to report
> > the results because it's not an inevitable problem.
> >
> > Meanwhile we also try to find a possible scenario of non-hotplugging to
> > explain the double-add warnings.
> 
> Hi Lei,
> 
> do you have any updates?  

Dear Paolo,

Thanks for kicking me :) 

TBH, thinking about the reliability of productive project (we use kvm-4.4),
we applied the patch you used in fedora pastebin, and
the bug seems gone after one month's testing.

diff --git a/source/x86/vmx.c b/source/x86/vmx.c
index 79012cf..efc611f 100644
--- a/source/x86/vmx.c
+++ b/source/x86/vmx.c
@@ -11036,8 +11036,9 @@ static void pi_post_block(struct kvm_vcpu *vcpu)
        unsigned int dest;
        unsigned long flags;
 
-       if (!kvm_arch_has_assigned_device(vcpu->kvm) ||
-               !irq_remapping_cap(IRQ_POSTING_CAP))
+       if ((vcpu->pre_pcpu == -1) &&
+               (!kvm_arch_has_assigned_device(vcpu->kvm) ||
+               !irq_remapping_cap(IRQ_POSTING_CAP)))
                return;

> I would like to get at least the first three
> patches in 4.13.
>
I think they are okay to me for upstream.

Thanks,
-Gonglei