From 78a780602075d8b00c98070fa26e389b3b3efa72 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Thu, 9 Dec 2021 08:54:29 -0700 Subject: [PATCH] io_uring: ensure task_work gets run as part of cancelations If we successfully cancel a work item but that work item needs to be processed through task_work, then we can be sleeping uninterruptibly in io_uring_cancel_generic() and never process it. Hence we don't make forward progress and we end up with an uninterruptible sleep warning. While in there, correct a comment that should be IFF, not IIF. Reported-and-tested-by: syzbot+21e6887c0be14181206d@syzkaller.appspotmail.com Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe --- fs/io_uring.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index c4f217613f56..d5ab0e9a3f29 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -9824,7 +9824,7 @@ static __cold void io_uring_drop_tctx_refs(struct task_struct *task) /* * Find any io_uring ctx that this task has registered or done IO on, and cancel - * requests. @sqd should be not-null IIF it's an SQPOLL thread cancellation. + * requests. @sqd should be not-null IFF it's an SQPOLL thread cancellation. */ static __cold void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd) @@ -9866,8 +9866,10 @@ static __cold void io_uring_cancel_generic(bool cancel_all, cancel_all); } - prepare_to_wait(&tctx->wait, &wait, TASK_UNINTERRUPTIBLE); + prepare_to_wait(&tctx->wait, &wait, TASK_INTERRUPTIBLE); + io_run_task_work(); io_uring_drop_tctx_refs(current); + /* * If we've seen completions, retry without waiting. This * avoids a race where a completion comes in before we did