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
..
acl.c	ext4: use current_time() for inode timestamps	2016-11-14 21:40:10 -05:00
acl.h
balloc.c
bitmap.c
block_validity.c
dir.c
ext4.h	ext4: remove unused function ext4_aligned_io()	2016-11-21 11:51:44 -05:00
ext4_extents.h
ext4_jbd2.c
ext4_jbd2.h
extents.c	ext4: use current_time() for inode timestamps	2016-11-14 21:40:10 -05:00
extents_status.c
extents_status.h
file.c	ext4: convert DAX faults to iomap infrastructure	2016-11-20 18:51:24 -05:00
fsync.c
hash.c
ialloc.c	ext4: avoid lockdep warning when inheriting encryption context	2016-11-21 11:52:44 -05:00
indirect.c
inline.c	ext4: only set S_DAX if DAX is really supported	2016-11-20 17:32:59 -05:00
inode.c	ext4: rip out DAX handling from direct IO path	2016-11-20 18:53:30 -05:00
ioctl.c	ext4: use current_time() for inode timestamps	2016-11-14 21:40:10 -05:00
Kconfig
Makefile
mballoc.c	ext4: fix stack memory corruption with 64k block size	2016-11-14 21:26:26 -05:00
mballoc.h
migrate.c
mmp.c
move_extent.c
namei.c	ext4: use current_time() for inode timestamps	2016-11-14 21:40:10 -05:00
page-io.c
readpage.c
resize.c
super.c	ext4: avoid lockdep warning when inheriting encryption context	2016-11-21 11:52:44 -05:00
symlink.c
sysfs.c
truncate.h
xattr.c	ext4: remove parameter from ext4_xattr_ibody_set()	2016-11-14 21:56:48 -05:00
xattr.h
xattr_security.c
xattr_trusted.c
xattr_user.c