From e4956dc7a84da074fd8dc10f7abd147f15b3ae58 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Tue, 13 Aug 2024 06:10:59 -0600 Subject: [PATCH] io_uring/sqpoll: annotate debug task == current with data_race() There's a debug check in io_sq_thread_park() checking if it's the SQPOLL thread itself calling park. KCSAN warns about this, as we should not be reading sqd->thread outside of sqd->lock. Just silence this with data_race(). The pointer isn't used for anything but this debug check. Reported-by: syzbot+2b946a3fd80caf971b21@syzkaller.appspotmail.com Signed-off-by: Jens Axboe --- io_uring/sqpoll.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/io_uring/sqpoll.c b/io_uring/sqpoll.c index b3722e5275e7..3b50dc9586d1 100644 --- a/io_uring/sqpoll.c +++ b/io_uring/sqpoll.c @@ -44,7 +44,7 @@ void io_sq_thread_unpark(struct io_sq_data *sqd) void io_sq_thread_park(struct io_sq_data *sqd) __acquires(&sqd->lock) { - WARN_ON_ONCE(sqd->thread == current); + WARN_ON_ONCE(data_race(sqd->thread) == current); atomic_inc(&sqd->park_pending); set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);