netdev - Re: [PATCH v2 0/3] vhost_task: Fix a bug where KVM wakes an exited task

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Message-ID: <aMwtd40q44q5uqwr@google.com>
Date: Thu, 18 Sep 2025 09:04:07 -0700
From: Sean Christopherson <seanjc@...gle.com>
To: Sebastian Andrzej Siewior <bigeasy@...utronix.de>
Cc: "Michael S. Tsirkin" <mst@...hat.com>, Paolo Bonzini <pbonzini@...hat.com>, 
	Jason Wang <jasowang@...hat.com>, kvm@...r.kernel.org, virtualization@...ts.linux.dev, 
	netdev@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2 0/3] vhost_task: Fix a bug where KVM wakes an exited task

On Thu, Sep 18, 2025, Sebastian Andrzej Siewior wrote:
> On 2025-09-18 11:09:05 [-0400], Michael S. Tsirkin wrote:
> > So how about switching to this approach then?
> > Instead of piling up fixes like we seem to do now ...

I don't have a strong preference for 6.17, beyond landing a fix of some kind.
I think there are three options for 6.17, in order of "least like to break
something":

 1. Sebastian's get_task_struct() fix
 2. This series, without the KILLED sanity check in __vhost_task_wake()
 3. This series, with my fixup (with which syzbot was happy)

Longer term, I'd still like to land everything though.

> > Sean?
> 
> Since I am in To: here. You want me to resent my diff as a proper patch?

Ya, I think it makes sense to harden against UAF even if we fix the KVM bug more
directly.