linux-stable/fs
Eric Biggers 2f8f5e76c7 ext4: avoid lockdep warning when inheriting encryption context
On a lockdep-enabled kernel, xfstests generic/027 fails due to a lockdep
warning when run on ext4 mounted with -o test_dummy_encryption:

    xfs_io/4594 is trying to acquire lock:
     (jbd2_handle
    ){++++.+}, at:
    [<ffffffff813096ef>] jbd2_log_wait_commit+0x5/0x11b

    but task is already holding lock:
     (jbd2_handle
    ){++++.+}, at:
    [<ffffffff813000de>] start_this_handle+0x354/0x3d8

The abbreviated call stack is:

 [<ffffffff813096ef>] ? jbd2_log_wait_commit+0x5/0x11b
 [<ffffffff8130972a>] jbd2_log_wait_commit+0x40/0x11b
 [<ffffffff813096ef>] ? jbd2_log_wait_commit+0x5/0x11b
 [<ffffffff8130987b>] ? __jbd2_journal_force_commit+0x76/0xa6
 [<ffffffff81309896>] __jbd2_journal_force_commit+0x91/0xa6
 [<ffffffff813098b9>] jbd2_journal_force_commit_nested+0xe/0x18
 [<ffffffff812a6049>] ext4_should_retry_alloc+0x72/0x79
 [<ffffffff812f0c1f>] ext4_xattr_set+0xef/0x11f
 [<ffffffff812cc35b>] ext4_set_context+0x3a/0x16b
 [<ffffffff81258123>] fscrypt_inherit_context+0xe3/0x103
 [<ffffffff812ab611>] __ext4_new_inode+0x12dc/0x153a
 [<ffffffff812bd371>] ext4_create+0xb7/0x161

When a file is created in an encrypted directory, ext4_set_context() is
called to set an encryption context on the new file.  This calls
ext4_xattr_set(), which contains a retry loop where the journal is
forced to commit if an ENOSPC error is encountered.

If the task actually were to wait for the journal to commit in this
case, then it would deadlock because a handle remains open from
__ext4_new_inode(), so the running transaction can't be committed yet.
Fortunately, __jbd2_journal_force_commit() avoids the deadlock by not
allowing the running transaction to be committed while the current task
has it open.  However, the above lockdep warning is still triggered.

This was a false positive which was introduced by: 1eaa566d36: jbd2:
track more dependencies on transaction commit

Fix the problem by passing the handle through the 'fs_data' argument to
ext4_set_context(), then using ext4_xattr_set_handle() instead of
ext4_xattr_set().  And in the case where no journal handle is specified
and ext4_set_context() has to open one, add an ENOSPC retry loop since
in that case it is the outermost transaction.

Signed-off-by: Eric Biggers <ebiggers@google.com>
2016-11-21 11:52:44 -05:00
..
9p Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
adfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
affs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
afs afs: call->operation_ID sometimes used as __be32 sometimes as u32 2016-10-13 17:03:52 +01:00
autofs4 autofs: refactor ioctl fn vector in iookup_dev_ioctl() 2016-10-11 15:06:31 -07:00
befs befs fixes for 4.9-rc1 2016-10-15 12:09:13 -07:00
bfs Merge remote-tracking branch 'ovl/rename2' into for-linus 2016-10-10 23:02:51 -04:00
btrfs Merge branch 'for-4.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux 2016-11-04 20:08:16 -07:00
cachefiles Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
ceph ceph: fix non static symbol warning 2016-10-18 12:30:32 +02:00
cifs CIFS: Retrieve uid and gid from special sid if enabled 2016-10-14 14:22:16 -05:00
coda Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
configfs Merge remote-tracking branch 'ovl/rename2' into for-linus 2016-10-10 23:02:51 -04:00
cramfs
crypto fscrypto: don't use on-stack buffer for key derivation 2016-11-13 21:56:25 -05:00
debugfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
devpts Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
dlm dlm: free workqueues after the connections 2016-10-10 09:54:00 -05:00
ecryptfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
efivarfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
efs
exofs fs: exofs: print a hex number after a 0x prefix 2016-10-27 18:43:43 -07:00
exportfs exportfs: be careful to only return expected errors. 2016-10-06 09:07:44 -04:00
ext2 ext2: use iomap_zero_range() for zeroing truncated page in DAX path 2016-11-20 20:47:07 -05:00
ext4 ext4: avoid lockdep warning when inheriting encryption context 2016-11-21 11:52:44 -05:00
f2fs fscrypt: Let fs select encryption index/tweak 2016-11-13 20:18:16 -05:00
fat Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
freevxfs
fscache
fuse Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
gfs2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
hfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
hfsplus Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
hostfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
hpfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
hugetlbfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
isofs isofs: Do not return EACCES for unknown filesystems 2016-10-18 11:28:21 +02:00
jbd2 jbd2: fix incorrect unlock on j_list_lock 2016-10-12 23:19:18 -04:00
jffs2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
jfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
kernfs kernfs: Add noop_fsync to supported kernfs_file_fops 2016-10-27 17:47:11 +02:00
lockd treewide: remove redundant #include <linux/kconfig.h> 2016-10-11 15:06:33 -07:00
logfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
minix Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
ncpfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
nfs NFS client bugfixes for Linux 4.9 2016-10-21 19:06:59 -07:00
nfs_common
nfsd nfsd: Fix general protection fault in release_lock_stateid() 2016-11-01 15:24:43 -04:00
nilfs2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
nls
notify fsnotify: clean up spinlock assertions 2016-10-07 18:46:26 -07:00
ntfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
ocfs2 ocfs2: fix memory leak in dlm_migrate_request_handler() 2016-10-11 15:06:30 -07:00
omfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
openpromfs fs: Replace CURRENT_TIME with current_time() for inode timestamps 2016-09-27 21:06:21 -04:00
orangefs orangefs: don't use d_time 2016-10-24 14:50:07 -04:00
overlayfs ovl: fsync after copy-up 2016-10-31 14:42:14 +01:00
proc proc: fix NULL dereference when reading /proc/<pid>/auxv 2016-10-27 18:43:43 -07:00
pstore Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
qnx4
qnx6
quota
ramfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
reiserfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
romfs
squashfs vfs: Remove {get,set,remove}xattr inode operations 2016-10-07 21:48:36 -04:00
sysfs Merge branch 'for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 2016-10-14 12:18:50 -07:00
sysv Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
tracefs fs: Replace CURRENT_TIME with current_time() for inode timestamps 2016-09-27 21:06:21 -04:00
ubifs ubifs: Fix regression in ubifs_readdir() 2016-10-28 14:48:31 +02:00
udf Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
ufs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
xfs Merge branch 'dax-4.10-iomap-pmd' into origin 2016-11-13 22:02:15 -05:00
aio.c fs/aio.c: eliminate redundant loads in put_aio_ring_file 2016-09-27 21:45:46 -04:00
anon_inodes.c
attr.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
bad_inode.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
binfmt_aout.c
binfmt_elf.c x86/coredump: Use pr_reg size, rather that TIF_IA32 flag 2016-09-14 21:28:10 +02:00
binfmt_elf_fdpic.c
binfmt_em86.c
binfmt_flat.c
binfmt_misc.c fs: Replace current_fs_time() with current_time() 2016-09-27 21:06:22 -04:00
binfmt_script.c
block_dev.c block: implement (some of) fallocate for block devices 2016-10-11 15:06:30 -07:00
buffer.c fs: use mapping_set_error instead of opencoded set_bit 2016-10-11 15:06:33 -07:00
char_dev.c
compat.c compat: remove compat_printk() 2016-09-27 21:20:53 -04:00
compat_binfmt_elf.c
compat_ioctl.c fs: compat_ioctl: add pretimeout functions for watchdogs 2016-09-24 09:27:18 +02:00
coredump.c
dax.c dax: rip out get_block based IO support 2016-11-20 20:48:36 -05:00
dcache.c
dcookies.c
direct-io.c consistent treatment of EFAULT on O_DIRECT read/write 2016-10-03 20:38:55 -04:00
drop_caches.c
eventfd.c
eventpoll.c
exec.c mm: replace get_user_pages_remote() write/force parameters with gup_flags 2016-10-19 08:12:02 -07:00
fcntl.c
fhandle.c
file.c fs/file: more unsigned file descriptors 2016-09-27 18:47:38 -04:00
file_table.c
filesystems.c
fs-writeback.c
fs_pin.c
fs_struct.c
inode.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
internal.h Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 13:04:49 -07:00
ioctl.c vfs: cap dedupe request structure size at PAGE_SIZE 2016-09-15 13:29:52 -07:00
iomap.c Merge branch 'dax-4.10-iomap-pmd' into origin 2016-11-13 22:02:15 -05:00
Kconfig dax: remove "depends on BROKEN" from FS_DAX_PMD 2016-11-08 11:35:16 +11:00
Kconfig.binfmt
libfs.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
locks.c locking, fs/locks: Add missing file_sem locks 2016-10-18 12:21:28 +02:00
Makefile
mbcache.c
mount.h mnt: Add a per mount namespace limit on the number of mounts 2016-09-30 12:46:48 -05:00
mpage.c
namei.c Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2016-10-14 17:23:33 -07:00
namespace.c This adds a new gcc plugin named "latent_entropy". It is designed to 2016-10-15 10:03:15 -07:00
no-block.c
nsfs.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
open.c xfs: reflink update for 4.9-rc1 2016-10-13 20:28:22 -07:00
pipe.c pipe: cap initial pipe capacity according to pipe-max-size limit 2016-10-11 15:06:32 -07:00
pnode.c mnt: Add a per mount namespace limit on the number of mounts 2016-09-30 12:46:48 -05:00
pnode.h mnt: Add a per mount namespace limit on the number of mounts 2016-09-30 12:46:48 -05:00
posix_acl.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
proc_namespace.c
read_write.c iov_iter: kernel-doc import_iovec() and rw_copy_check_uvector() 2016-10-14 20:00:34 -04:00
readdir.c
select.c fs/select: add vmalloc fallback for select(2) 2016-10-11 15:06:30 -07:00
seq_file.c seq/proc: modify seq_put_decimal_[u]ll to take a const char *, not char 2016-10-07 18:46:30 -07:00
signalfd.c
splice.c fix ITER_PIPE interaction with direct_IO 2016-10-10 13:36:06 -04:00
stack.c
stat.c
statfs.c
super.c fs/super.c: don't fool lockdep in freeze_super() and thaw_super() paths 2016-10-14 20:41:59 -04:00
sync.c
timerfd.c
userfaultfd.c
utimes.c Merge remote-tracking branch 'jk/vfs' into work.misc 2016-10-08 11:06:08 -04:00
xattr.c vfs: Remove {get,set,remove}xattr inode operations 2016-10-07 21:48:36 -04:00