[PATCH] io_uring: Use system_dfl_wq instead of system_unbound_wq to fix warning

[PATCH] io_uring: Use system_dfl_wq instead of system_unbound_wq to fix warning

[Nathan Chancellor]

Commit de7341ffe49e ("io_uring: switch normal task_work to a mpscq")
added a use of system_unbound_wq, which is deprecated in favor of
system_dfl_wq added by commit 128ea9f6ccfb ("workqueue: Add
system_percpu_wq and system_dfl_wq"). An upcoming warning in the
workqueue tree flags this with:

  workqueue: work func io_tctx_fallback_work enqueued on deprecated workqueue. Use system_{percpu|dfl}_wq instead.

Switch to system_dfl_wq to clear up the warning.

Fixes: de7341ffe49e ("io_uring: switch normal task_work to a mpscq")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
---
 io_uring/tw.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/io_uring/tw.c b/io_uring/tw.c
index e74372233f40..48a9d09ef582 100644
--- a/io_uring/tw.c
+++ b/io_uring/tw.c
@@ -55,7 +55,7 @@ static void io_fallback_tw(struct io_uring_task *tctx)
 	 * the queued work) stay around until the drain has run.
 	 */
 	get_task_struct(tctx->task);
-	if (!queue_work(system_unbound_wq, &tctx->fallback_work))
+	if (!queue_work(system_dfl_wq, &tctx->fallback_work))
 		put_task_struct(tctx->task);
 }
 

---
base-commit: d9b710f683dc68b5c0b7dd0c6c64aeb5d27a1ac4
change-id: 20260616-io_uring-fix-wq-warning-75ede0708655

Best regards,
--  
Cheers,
Nathan

Re: [PATCH] io_uring: Use system_dfl_wq instead of system_unbound_wq to fix warning

[Jens Axboe]

On Tue, 16 Jun 2026 14:39:02 -0700, Nathan Chancellor wrote:
> Commit de7341ffe49e ("io_uring: switch normal task_work to a mpscq")
> added a use of system_unbound_wq, which is deprecated in favor of
> system_dfl_wq added by commit 128ea9f6ccfb ("workqueue: Add
> system_percpu_wq and system_dfl_wq"). An upcoming warning in the
> workqueue tree flags this with:
> 
>   workqueue: work func io_tctx_fallback_work enqueued on deprecated workqueue. Use system_{percpu|dfl}_wq instead.
> 
> [...]

Applied, thanks!

[1/1] io_uring: Use system_dfl_wq instead of system_unbound_wq to fix warning
      commit: ff3ac1a0bd75400375678c0f81c2b613cbc03e14

Best regards,
-- 
Jens Axboe