Commit d119bd2e authored by Yu Kuai's avatar Yu Kuai
Browse files

md/md-llbitmap: fix percpu_ref not resurrected on suspend timeout 

When llbitmap_suspend_timeout() times out waiting for percpu_ref to
become zero, it returns -ETIMEDOUT without resurrecting the percpu_ref.
The caller (md_llbitmap_daemon_fn) then continues to the next page
without calling llbitmap_resume(), leaving the percpu_ref in a killed
state permanently.

Fix this by resurrecting the percpu_ref before returning the error,
ensuring the page control structure remains usable for subsequent
operations.

Link: https://lore.kernel.org/linux-raid/20260123182623.3718551-3-yukuai@fnnas.com


Fixes: 5ab829f1 ("md/md-llbitmap: introduce new lockless bitmap")
Signed-off-by: default avatarYu Kuai <yukuai@fnnas.com>
Reviewed-by: default avatarLi Nan <linan122@huawei.com>
parent cd1635d8

drivers/md/md-llbitmap.c

+3 −1
Original line number Diff line number Diff line
@@ -712,8 +712,10 @@ static int llbitmap_suspend_timeout(struct llbitmap *llbitmap, int page_idx) 
	percpu_ref_kill(&pctl->active);



	if (!wait_event_timeout(pctl->wait, percpu_ref_is_zero(&pctl->active),

			llbitmap->mddev->bitmap_info.daemon_sleep * HZ))

			llbitmap->mddev->bitmap_info.daemon_sleep * HZ)) {

		percpu_ref_resurrect(&pctl->active);

		return -ETIMEDOUT;

	}



	return 0;

}