From 8629397e6e2753bb4cc62ba48a12e1d4d912b6a4 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Fri, 26 Feb 2021 13:46:49 -0700 Subject: [PATCH] io_uring: don't use complete_all() on SQPOLL thread exit We want to reuse this completion, and a single complete should do just fine. Ensure that we park ourselves first if requested, as that is what lead to the initial deadlock in this area. If we've got someone attempting to park us, then we can't proceed without having them finish first. Fixes: 37d1e2e3642e ("io_uring: move SQPOLL thread io-wq forked worker") Signed-off-by: Jens Axboe --- fs/io_uring.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 9d6696ff5748..904bf0fecc36 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -6783,10 +6783,13 @@ static int io_sq_thread(void *data) io_run_task_work(); + if (io_sq_thread_should_park(sqd)) + io_sq_thread_parkme(sqd); + /* * Clear thread under lock so that concurrent parks work correctly */ - complete_all(&sqd->completion); + complete(&sqd->completion); mutex_lock(&sqd->lock); sqd->thread = NULL; list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) { -- 2.34.1