From: Joao Martins <joao.m.martins@oracle.com>
To: Alejandro Jimenez <alejandro.j.jimenez@oracle.com>,
Sean Christopherson <seanjc@google.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
"dengqiao . joey" <dengqiao.joey@bytedance.com>,
Maxim Levitsky <mlevitsk@redhat.com>,
Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>,
Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH 0/2] KVM: SVM: Set pCPU during IRTE update if vCPU is running
Date: Wed, 9 Aug 2023 11:30:03 +0100 [thread overview]
Message-ID: <c9a1a5cc-7e84-e887-f4e3-8396cc8ce494@oracle.com> (raw)
In-Reply-To: <20230808233132.2499764-1-seanjc@google.com>
On 09/08/2023 00:31, Sean Christopherson wrote:
> Fix a bug where KVM doesn't set the pCPU affinity for running vCPUs when
> updating IRTE routing. Not setting the pCPU means the IOMMU will signal
> the wrong pCPU's doorbell until the vCPU goes through a put+load cycle.
>
Or also framed as an inefficiency that we depend on the GALog (for a running
vCPU) for interrupt delivery until the put+load cycle happens. I don't think I
ever reproduced the missed interrupt case in our stress testing.
> I waffled for far too long between making this one patch or two. Moving
> the lock doesn't make all that much sense as a standalone patch, but in the
> end, I decided that isolating the locking change would be useful in the
> unlikely event that it breaks something. If anyone feels strongly about
> making this a single patch, I have no objection to squashing these together.
>
IMHO, as two patches looks better;
For what is worth:
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
I think Alejandro had reported his testing as successful here:
https://lore.kernel.org/kvm/caefe41b-2736-3df9-b5cd-b81fc4c30ff0@oracle.com/
OTOH, he didn't give the Tested-by explicitly
next prev parent reply other threads:[~2023-08-09 10:30 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-08-08 23:31 Sean Christopherson
2023-08-08 23:31 ` [PATCH 1/2] KVM: SVM: Take and hold ir_list_lock when updating vCPU's Physical ID entry Sean Christopherson
2023-08-08 23:31 ` [PATCH 2/2] KVM: SVM: Set target pCPU during IRTE update if target vCPU is running Sean Christopherson
2023-08-09 10:30 ` Joao Martins [this message]
2023-08-09 14:23 ` [PATCH 0/2] KVM: SVM: Set pCPU during IRTE update if " Sean Christopherson
2023-08-09 14:58 ` Alejandro Jimenez
2023-08-18 0:12 ` Sean Christopherson
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=c9a1a5cc-7e84-e887-f4e3-8396cc8ce494@oracle.com \
--to=joao.m.martins@oracle.com \
--cc=alejandro.j.jimenez@oracle.com \
--cc=dengqiao.joey@bytedance.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mlevitsk@redhat.com \
--cc=pbonzini@redhat.com \
--cc=seanjc@google.com \
--cc=suravee.suthikulpanit@amd.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®