Tejun Heo df6a58c5c5 kernfs: don't depend on d_find_any_alias() when generating notifications ... kernfs_notify_workfn() sends out file modified events for the scheduled kernfs_nodes. Because the modifications aren't from userland, it doesn't have the matching file struct at hand and can't use fsnotify_modify(). Instead, it looked up the inode and then used d_find_any_alias() to find the dentry and used fsnotify_parent() and fsnotify() directly to generate notifications. The assumption was that the relevant dentries would have been pinned if there are listeners, which isn't true as inotify doesn't pin dentries at all and watching the parent doesn't pin the child dentries even for dnotify. This led to, for example, inotify watchers not getting notifications if the system is under memory pressure and the matching dentries got reclaimed. It can also be triggered through /proc/sys/vm/drop_caches or a remount attempt which involves shrinking dcache. fsnotify_parent() only uses the dentry to access the parent inode, which kernfs can do easily. Update kernfs_notify_workfn() so that it uses fsnotify() directly for both the parent and target inodes without going through d_find_any_alias(). While at it, supply the target file name to fsnotify() from kernfs_node->name. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Evgeny Vereshchagin <evvers@ya.ru> Fixes: d911d98748 ("kernfs: make kernfs_notify() trigger inotify events too") Cc: John McCutchan <john@johnmccutchan.com> Cc: Robert Love <rlove@rlove.org> Cc: Eric Paris <eparis@parisplace.org> Cc: stable@vger.kernel.org # v3.16+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2016-08-31 14:48:52 +02:00
..
dir.c	vfs: make the string hashes salt the hash	2016-06-10 20:21:46 -07:00
file.c	kernfs: don't depend on d_find_any_alias() when generating notifications	2016-08-31 14:48:52 +02:00
inode.c	switch ->setxattr() to passing dentry and inode separately	2016-05-27 20:09:16 -04:00
Kconfig	kernfs: add CONFIG_KERNFS	2014-02-07 16:08:57 -08:00
kernfs-internal.h	switch ->setxattr() to passing dentry and inode separately	2016-05-27 20:09:16 -04:00
Makefile
mount.c	vfs: Generalize filesystem nodev handling.	2016-06-23 15:41:57 -05:00
symlink.c	switch ->get_link() to delayed_call, kill ->put_link()	2015-12-30 13:01:03 -05:00