Re: [PATCH 0/3] Rework work queue usage

[htejun@gmail.com]

Hello,

On Thu, Mar 28, 2024 at 02:02:47PM -0500, Lucas De Marchi wrote:
> On Thu, Mar 28, 2024 at 11:21:44AM -0700, Matthew Brost wrote:
> > Avoid sleeping or grabbing locks in work queues shared with the system.
> > Recent changes to work queues [1] have exposed deadlocks [2] in Xe.

Can you elaborate it a bit? I'm having a bit of hard time imagining how the
latest workqueue changes would have exposed deadlocks.

> I think we need some of this information in the commit message in patch
> 1. Because patch 1 simply says it's moving to a device private wq to
> avoid hogging the system one, but the issue is much more serious.
> 
> Also, is the "Fixes:"  really correct? It seems more like a regression
> from the wq changes and there could be other drivers showing similar
> issues now. But it could alos be my lack of understanding of the real
> issue.

I don't have enough context to tell whether this is a workqueue problem but
if so we should definitely fix workqueue.

Thanks.

-- 
tejun