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Date: Wed, 8 May 2024 14:42:38 +0200
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Subject: Re: [BUG][v6.9-rc6] Deadlock with: Revert "drm/qxl: simplify
 qxl_fence_wait"
To: Steven Rostedt <rostedt@goodmis.org>, David Airlie <airlied@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
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From: Anders Blomdell <anders.blomdell@gmail.com>
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On 2024-05-07 11:03, Steven Rostedt wrote:
> On Tue, 7 May 2024 15:54:21 +1000
> David Airlie <airlied@redhat.com> wrote:
> 
>> I expec this will reintroduce the other problems that caused this
>> change in the first place, but I think this should at least bring us
>> back to regression equilibrium. I can't recommend anyone use qxl hw
>> over virtio-gpu hw in their VMs, since virtio-gpu is actually hw
>> designed for virt.
> 
> I agree that it will likely cause the issues that this was addressing
> to come back, but you can't have a fix that introduces a deadlock.
> 
> Perhaps the deadlock didn't exist before, and the printk updates
> changed the way it works to introduce it now?
It deadlocks on 6.8.8 under qemu/kvm,  reverting the patch fixes the problem there as well (6.8.7 hangs as well, but I have not tested reverting on that version)

/Anders