Re: PROBLEM: io_uring hang causing uninterruptible sleep state on 6.6.59

[Jens Axboe <axboe@kernel.dk>]

On 11/3/24 5:01 PM, Keith Busch wrote:
> On Sun, Nov 03, 2024 at 04:53:27PM -0700, Jens Axboe wrote:
>> On 11/3/24 4:47 PM, Andrew Marshall wrote:
>>> I identified f4ce3b5d26ce149e77e6b8e8f2058aa80e5b034e as the likely
>>> problematic commit simply by browsing git log. As indicated above;
>>> reverting that atop 6.6.59 results in success. Since it is passing on
>>> 6.11.6, I suspect there is some missing backport to 6.6.x, or some
>>> other semantic merge conflict. Unfortunately I do not have a compact,
>>> minimal reproducer, but can provide my large one (it is testing a
>>> larger build process in a VM) if needed?there are some additional
>>> details in the above-linked downstream bug report, though. I hope that
>>> having identified the problematic commit is enough for someone with
>>> more context to go off of. Happy to provide more information if
>>> needed.
>>
>> Don't worry about not having a reproducer, having the backport commit
>> pin pointed will do just fine. I'll take a look at this.
> 
> I think stable is missing:
> 
>   6b231248e97fc3 ("io_uring: consolidate overflow flushing")

I think you need to go back further than that, this one already
unconditionally holds ->uring_lock around overflow flushing...

-- 
Jens Axboe