From 0dd89bb8f089d80032edcac668edac2c182d35ec Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Thu, 2 Dec 2021 19:40:15 -0700 Subject: [PATCH] io-wq: don't retry task_work creation failure on fatal conditions [ Upstream commit a226abcd5d427fe9d42efc442818a4a1821e2664 ] We don't want to be retrying task_work creation failure if there's an actual signal pending for the parent task. If we do, then we can enter an infinite loop of perpetually retrying and each retry failing with -ERESTARTNOINTR because a signal is pending. Fixes: 3146cba99aa2 ("io-wq: make worker creation resilient against signals") Reported-by: Florian Fischer Link: https://lore.kernel.org/io-uring/20211202165606.mqryio4yzubl7ms5@pasture/ Tested-by: Florian Fischer Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- fs/io-wq.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/fs/io-wq.c b/fs/io-wq.c index 8c6131565754..e8f77903d775 100644 --- a/fs/io-wq.c +++ b/fs/io-wq.c @@ -711,6 +711,13 @@ static bool io_wq_work_match_all(struct io_wq_work *work, void *data) static inline bool io_should_retry_thread(long err) { + /* + * Prevent perpetual task_work retry, if the task (or its group) is + * exiting. + */ + if (fatal_signal_pending(current)) + return false; + switch (err) { case -EAGAIN: case -ERESTARTSYS: