On 4/18/24 16:26, Takashi Iwai wrote:
> On Thu, 18 Apr 2024 16:06:52 +0200,
> Nam Cao wrote:
>>
>> On 2024-04-18 Harshit Mogalapalli wrote:
>>> While fuzzing 5.15.y kernel with Syzkaller, we noticed a INFO: task hu=
ng
>>> bug in fb_deferred_io_work()
>>
>> Which framebuffer device are you using exactly? It is possible that
>> the problem is with the device driver, not core framebuffer.
>
> Note that it was already known that using flush_delayed_work() caused
> a problem.  See the thread of the fix patch:
>    https://lore.kernel.org/all/20230129082856.22113-1-tiwai@suse.de/

Harshit reported the hung tasks with kernel v5.15-stable, and can even rep=
roduce
that issue with kernel v6.9-rc4 although it has all of your patches from
that referenced mail thread applied.
So, what does your statement that "it was already known that it causes pro=
blems" exactly mean?
Can it be fixed? Is someone looking into fixing it?

> BTW, the problem is seen with bochs drm.

Helge