linux/fs/fuse
Miklos Szeredi 2d84a2d19b fuse: fix possibly missed wake-up after abort
In current fuse_drop_waiting() implementation it's possible that
fuse_wait_aborted() will not be woken up in the unlikely case that
fuse_abort_conn() + fuse_wait_aborted() runs in between checking
fc->connected and calling atomic_dec(&fc->num_waiting).

Do the atomic_dec_and_test() unconditionally, which also provides the
necessary barrier against reordering with the fc->connected check.

The explicit smp_mb() in fuse_wait_aborted() is not actually needed, since
the spin_unlock() in fuse_abort_conn() provides the necessary RELEASE
barrier after resetting fc->connected.  However, this is not a performance
sensitive path, and adding the explicit barrier makes it easier to
document.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: b8f95e5d13 ("fuse: umount should wait for all requests")
Cc: <stable@vger.kernel.org> #v4.19
2018-11-09 15:52:16 +01:00
..
acl.c fuse: Support fuse filesystems outside of init_user_ns 2018-03-20 17:11:44 +01:00
control.c fuse: introduce fc->bg_lock 2018-09-28 16:43:22 +02:00
cuse.c fuse: Support fuse filesystems outside of init_user_ns 2018-03-20 17:11:44 +01:00
dev.c fuse: fix possibly missed wake-up after abort 2018-11-09 15:52:16 +01:00
dir.c fuse: enable caching of symlinks 2018-10-15 15:43:07 +02:00
file.c Merge branch 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-11-01 19:58:52 -07:00
fuse_i.h fuse: enable caching of symlinks 2018-10-15 15:43:07 +02:00
inode.c fuse: enable caching of symlinks 2018-10-15 15:43:07 +02:00
Kconfig fuse: Add posix ACL support 2016-10-01 07:32:32 +02:00
Makefile fuse: split out readdir.c 2018-09-28 16:43:23 +02:00
readdir.c fuse: use iversion for readdir cache verification 2018-10-01 10:07:05 +02:00
xattr.c fuse: Ensure posix acls are translated outside of init_user_ns 2018-05-31 12:26:10 +02:00