Re: [PATCH v4 0/2] workqueue: Add warnings and check WQ flags usage

[Tetsuo Handa]

On 2026/06/01 23:47, Tejun Heo wrote:
> On Mon, Jun 01, 2026 at 07:12:28AM +0900, Tetsuo Handa wrote:
>> I've spent more than one year for updating all in-tree users who are
>> flushing kernel global workqueues. Please see a message from Linus at
>> https://lkml.kernel.org/r/CAHk-=whWreGjEQ6yasspzBrNnS7EQiL+SknToWt=SzUh4XomyQ@xxxxxxxxxxxxxx .
>>
>> Please never try to emit WARNING: or BUG: message just for letting developers
>> update their code. If you can't use panic() instead of WARN*() or BUG*(), you
>> should not use WARN*() or BUG*(). The patch author who changes the behavior of
>> in-tree code is responsible for updating all in-tree code.
> 
> I don't think a statement this blanket makes sense. I scanned the existing
> linux-next tree and there were a handful that were missed (I didn't find out
> whether they are new ones in linux-next or ones that were misseds from
> mainline tho). Let's just apply the nvme-tcp patch and move on.

Not all users are quickly accepting patches. Please apply all fixes *before* you start
emitting WARNING: message. You are currently making linux-next tree untestable by syzbot.

> 
> Thanks.
> 

Mark Brown, please skip WQ changes from linux-next until all fixes are applied.

Linus, please be sure to skip WQ changes in the upcoming merge window if some fix
does not get applied in time for the merge window. (Of course, applying all fixes
before we start emitting WARNING: message is desirable for bisectability, even if
all fixes are get applied in time for the merge window...)