Amir Goldstein 623af4f538 fsnotify: fix wrong lockdep annotations ... Commit 6960b0d909 ("fsnotify: change locking order") changed some of the mark_mutex locks in direct reclaim path to use: mutex_lock_nested(&group->mark_mutex, SINGLE_DEPTH_NESTING); This change is explained: "...It uses nested locking to avoid deadlock in case we do the final iput() on an inode which still holds marks and thus would take the mutex again when calling fsnotify_inode_delete() in destroy_inode()." The problem is that the mutex_lock_nested() is not a nested lock at all. In fact, it has the opposite effect of preventing lockdep from warning about a very possible deadlock. Due to these wrong annotations, a deadlock that was introduced with nfsd filecache in kernel v5.4 went unnoticed in v5.4.y for over two years until it was reported recently by Khazhismel Kumykov, only to find out that the deadlock was already fixed in kernel v5.5. Fix the wrong lockdep annotations. Cc: Khazhismel Kumykov <khazhy@google.com> Fixes: 6960b0d909 ("fsnotify: change locking order") Link: https://lore.kernel.org/r/20220321112310.vpr7oxro2xkz5llh@quack3.lan/ Link: https://lore.kernel.org/r/20220422120327.3459282-4-amir73il@gmail.com Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>		2022-04-25 14:37:08 +02:00
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dnotify	dnotify: move dnotify sysctl to dnotify.c	2022-01-22 08:33:34 +02:00
fanotify	fsnotify: optimize FS_MODIFY events with no ignored masks	2022-02-24 14:05:18 +01:00
inotify	inotify: move control flags from mask to mark flags	2022-04-25 14:37:06 +02:00
fdinfo.c	inotify: show inotify mask flags in proc fdinfo	2022-04-25 14:37:03 +02:00
fdinfo.h	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
fsnotify.c	inotify: move control flags from mask to mark flags	2022-04-25 14:37:06 +02:00
fsnotify.h	fsnotify: count all objects with attached connectors	2021-08-11 13:50:48 +02:00
group.c	fsnotify: clarify object type argument	2021-12-15 14:04:03 +01:00
Kconfig	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
Makefile	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
mark.c	fsnotify: fix wrong lockdep annotations	2022-04-25 14:37:08 +02:00
notification.c	fsnotify: Pass group argument to free_event	2021-10-27 12:34:18 +02:00