Darrick J. Wong 195f9e1a54 vfs: remove lockdep bogosity in __sb_start_write ... [ Upstream commit 22843291ef ] __sb_start_write has some weird looking lockdep code that claims to exist to handle nested freeze locking requests from xfs. The code as written seems broken -- if we think we hold a read lock on any of the higher freeze levels (e.g. we hold SB_FREEZE_WRITE and are trying to lock SB_FREEZE_PAGEFAULT), it converts a blocking lock attempt into a trylock. However, it's not correct to downgrade a blocking lock attempt to a trylock unless the downgrading code or the callers are prepared to deal with that situation. Neither __sb_start_write nor its callers handle this at all. For example: sb_start_pagefault ignores the return value completely, with the result that if xfs_filemap_fault loses a race with a different thread trying to fsfreeze, it will proceed without pagefault freeze protection (thereby breaking locking rules) and then unlocks the pagefault freeze lock that it doesn't own on its way out (thereby corrupting the lock state), which leads to a system hang shortly afterwards. Normally, this won't happen because our ownership of a read lock on a higher freeze protection level blocks fsfreeze from grabbing a write lock on that higher level. *However*, if lockdep is offline, lock_is_held_type unconditionally returns 1, which means that percpu_rwsem_is_held returns 1, which means that __sb_start_write unconditionally converts blocking freeze lock attempts into trylocks, even when we *don't* hold anything that would block a fsfreeze. Apparently this all held together until 5.10-rc1, when bugs in lockdep caused lockdep to shut itself off early in an fstests run, and once fstests gets to the "race writes with freezer" tests, kaboom. This might explain the long trail of vanishingly infrequent livelocks in fstests after lockdep goes offline that I've never been able to diagnose. We could fix it by spinning on the trylock if wait==true, but AFAICT the locking works fine if lockdep is not built at all (and I didn't see any complaints running fstests overnight), so remove this snippet entirely. NOTE: Commit f4b554af99 in 2015 created the current weird logic (which used to exist in a different form in commit 5accdf82ba from 2012) in __sb_start_write. XFS solved this whole problem in the late 2.6 era by creating a variant of transactions (XFS_TRANS_NO_WRITECOUNT) that don't grab intwrite freeze protection, thus making lockdep's solution unnecessary. The commit claims that Dave Chinner explained that the trylock hack + comment could be removed, but nobody ever did. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Sasha Levin <sashal@kernel.org>		2020-11-24 13:29:01 +01:00
..
9p	9P: Cast to loff_t before multiplying	2020-11-05 11:43:34 +01:00
adfs	Merge branch 'work.adfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2019-07-19 11:33:22 -07:00
affs	affs: fix basic permission bits to actually work	2020-09-09 19:12:34 +02:00
afs	afs: Fix warning due to unadvanced marshalling pointer	2020-11-18 19:20:18 +01:00
autofs	autofs: fix a leak in autofs_expire_indirect()	2019-10-25 00:03:11 -04:00
befs	fs: Fill in max and min timestamps in superblock	2019-08-30 07:27:17 -07:00
bfs	fs: Fill in max and min timestamps in superblock	2019-08-30 07:27:17 -07:00
btrfs	btrfs: fix potential overflow in cluster_pages_for_defrag on 32bit arch	2020-11-18 19:20:30 +01:00
cachefiles	cachefiles: Handle readpage error correctly	2020-11-05 11:43:36 +01:00
ceph	ceph: promote to unsigned long long before shifting	2020-11-05 11:43:34 +01:00
cifs	Convert trailing spaces and periods in path components	2020-11-18 19:20:34 +01:00
coda	y2038: add inode timestamp clamping	2019-09-19 09:42:37 -07:00
configfs	configfs: fix config_item refcnt leak in configfs_rmdir()	2020-05-27 17:46:30 +02:00
cramfs	cramfs: fix usage on non-MTD device	2019-11-23 21:44:49 -05:00
crypto	fscrypt: don't evict dirty inodes after removing key	2020-03-18 07:17:53 +01:00
debugfs	debugfs: Fix module state check condition	2020-09-17 13:47:55 +02:00
devpts	devpts_pty_kill(): don't bother with d_delete()	2019-09-03 09:30:56 -04:00
dlm	fs: dlm: fix configfs memory leak	2020-10-29 09:58:03 +01:00
ecryptfs	ecryptfs: replace BUG_ON with error handling code	2020-02-28 17:22:26 +01:00
efivarfs	efivarfs: Replace invalid slashes with exclamation marks in dentries.	2020-11-01 12:01:02 +01:00
efs	fs: Fill in max and min timestamps in superblock	2019-08-30 07:27:17 -07:00
erofs	erofs: derive atime instead of leaving it empty	2020-11-18 19:20:28 +01:00
exportfs	exportfs_decode_fh(): negative pinned may become positive without the parent locked	2019-11-10 11:56:05 -05:00
ext2	ext2: don't update mtime on COW faults	2020-09-09 19:12:30 +02:00
ext4	ext4: unlock xattr_sem properly in ext4_inline_data_truncate()	2020-11-18 19:20:28 +01:00
f2fs	f2fs: handle errors of f2fs_get_meta_page_nofail	2020-11-05 11:43:14 +01:00
fat	fat: don't allow to mount if the FAT length == 0	2020-06-17 16:40:36 +02:00
freevxfs	fs: Fill in max and min timestamps in superblock	2019-08-30 07:27:17 -07:00
fscache	Revert "Merge tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs"	2019-07-10 18:43:43 -07:00
fuse	fuse: fix page dereference after free	2020-11-01 12:01:05 +01:00
gfs2	gfs2: check for live vs. read-only file system in gfs2_fitrim	2020-11-18 19:20:22 +01:00
hfs	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
hfsplus	hfsplus: fix crash and filesystem corruption when deleting files	2020-04-17 10:50:22 +02:00
hostfs	This pull request contains the following changes for UML:	2019-05-12 17:52:13 -04:00
hpfs	fs: hpfs: Initialize filesystem timestamp ranges	2019-08-30 08:11:25 -07:00
hugetlbfs	hugetlbfs: prevent filesystem stacking of hugetlbfs	2020-09-03 11:26:48 +02:00
iomap	iomap: fix WARN_ON_ONCE() from unprivileged users	2020-10-29 09:58:06 +01:00
isofs	y2038: add inode timestamp clamping	2019-09-19 09:42:37 -07:00
jbd2	jbd2: fix up sparse warnings in checkpoint code	2020-11-18 19:20:30 +01:00
jffs2	jffs2: fix UAF problem	2020-08-26 10:40:56 +02:00
jfs	y2038: add inode timestamp clamping	2019-09-19 09:42:37 -07:00
kernfs	kernfs: do not call fsnotify() with name without a parent	2020-08-19 08:16:12 +02:00
lockd	lockd: Make two symbols static	2019-07-03 17:52:09 -04:00
minix	fs/minix: remove expected error message in block_to_path()	2020-08-21 13:05:37 +02:00
nfs	NFSv4.2: support EXCHGID4_FLAG_SUPP_FENCE_OPS 4.2 EXCHANGE_ID flag	2020-11-05 11:43:31 +01:00
nfs_common	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
nfsd	NFSD: Add missing NFSv2 .pc_func methods	2020-11-05 11:43:31 +01:00
nilfs2	nilfs2: fix null pointer dereference at nilfs_segctor_do_construct()	2020-06-17 16:40:29 +02:00
nls	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
notify	fanotify: fix ignore mask logic for events on child and on dir	2020-06-17 16:40:24 +02:00
ntfs	ntfs: add check for mft record size in superblock	2020-10-29 09:58:03 +01:00
ocfs2	ocfs2: initialize ip_next_orphan	2020-11-18 19:20:30 +01:00
omfs	fs: omfs: Initialize filesystem timestamp ranges	2019-08-30 08:11:25 -07:00
openpromfs	Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2019-07-19 10:42:02 -07:00
orangefs	orangefs: get rid of knob code...	2020-08-21 13:05:29 +02:00
overlayfs	ovl: fix unneeded call to ovl_change_flags()	2020-07-22 09:33:12 +02:00
proc	mm, oom_adj: don't loop through tasks in __set_oom_adj when not necessary	2020-10-29 09:57:45 +01:00
pstore	pstore: Fix linking when crypto API disabled	2020-08-19 08:16:27 +02:00
qnx4	fs: Fill in max and min timestamps in superblock	2019-08-30 07:27:17 -07:00
qnx6	fs: Fill in max and min timestamps in superblock	2019-08-30 07:27:17 -07:00
quota	quota: clear padding in v2r1_mem2diskdqb()	2020-10-29 09:57:42 +01:00
ramfs	ramfs: fix nommu mmap with gaps in the page cache	2020-10-29 09:57:53 +01:00
reiserfs	reiserfs: Fix memory leak in reiserfs_parse_options()	2020-10-29 09:58:08 +01:00
romfs	romfs: fix uninitialized memory leak in romfs_dev_read()	2020-08-26 10:40:51 +02:00
squashfs	Merge branch 'work.mount2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2019-09-19 10:06:57 -07:00
sysfs	Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2019-07-19 10:42:02 -07:00
sysv	fs: sysv: Initialize filesystem timestamp ranges	2019-08-30 07:27:18 -07:00
tracefs	tracing: Do not create tracefs files if tracefs lockdown is in effect	2019-10-12 20:49:07 -04:00
ubifs	ubifs: mount_ubifs: Release authentication resource in error handling path	2020-11-05 11:43:32 +01:00
udf	udf: Fix memory leak when mounting	2020-11-05 11:43:29 +01:00
ufs	fs/ufs: avoid potential u32 multiplication overflow	2020-08-21 13:05:37 +02:00
unicode	unicode: make array 'token' static const, makes object smaller	2019-09-17 11:48:24 -04:00
verity	fs-verity: support builtin file signatures	2019-08-12 19:33:50 -07:00
xfs	xfs: fix a missing unlock on error in xfs_fs_map_blocks	2020-11-18 19:20:27 +01:00
Kconfig	fs-verity for 5.4	2019-09-18 16:59:14 -07:00
Kconfig.binfmt	binfmt_flat: make support for old format binaries optional	2019-06-24 09:16:47 +10:00
Makefile	fs-verity for 5.4	2019-09-18 16:59:14 -07:00
aio.c	aio: fix async fsync creds	2020-06-17 16:40:24 +02:00
anon_inodes.c	Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2019-07-19 10:42:02 -07:00
attr.c	utimes: Clamp the timestamps in notify_change()	2020-02-11 04:35:12 -08:00
bad_inode.c	…
binfmt_aout.c	treewide: Add SPDX license identifier for more missed files	2019-05-21 10:50:45 +02:00
binfmt_elf.c	fs/binfmt_elf.c: allocate initialized memory in fill_thread_core_info()	2020-06-03 08:21:27 +02:00
binfmt_elf_fdpic.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152	2019-05-30 11:26:32 -07:00
binfmt_em86.c	treewide: Add SPDX license identifier for more missed files	2019-05-21 10:50:45 +02:00
binfmt_flat.c	binfmt_flat: revert "binfmt_flat: don't offset the data start"	2020-09-03 11:26:39 +02:00
binfmt_misc.c	Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2019-07-19 10:42:02 -07:00
binfmt_script.c	treewide: Add SPDX license identifier for more missed files	2019-05-21 10:50:45 +02:00
block_dev.c	bdev: Reduce time holding bd_mutex in sync in blkdev_close()	2020-10-01 13:17:55 +02:00
buffer.c	fs: Don't invalidate page buffers in block_write_full_page()	2020-11-05 11:43:24 +01:00
char_dev.c	chardev: Avoid potential use-after-free in 'chrdev_open()'	2020-01-14 20:08:18 +01:00
compat.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500	2019-06-19 17:09:55 +02:00
compat_binfmt_elf.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 193	2019-05-30 11:29:21 -07:00
compat_ioctl.c	fix compat handling of FICLONERANGE, FIDEDUPERANGE and FS_IOC_FIEMAP	2020-01-09 10:20:05 +01:00
coredump.c	coredump: fix crash when umh is disabled	2020-05-14 07:58:27 +02:00
d_path.c	fs: fix NULL dereference due to data race in prepend_path()	2020-10-29 09:57:45 +01:00
dax.c	dax: pass NOWAIT flag to iomap_apply	2020-03-05 16:43:36 +01:00
dcache.c	fix dget_parent() fastpath race	2020-10-01 13:17:19 +02:00
dcookies.c	treewide: Add SPDX license identifier for missed files	2019-05-21 10:50:45 +02:00
direct-io.c	fs/direct-io.c: fix kernel-doc warning	2019-10-14 15:04:01 -07:00
drop_caches.c	fs: avoid softlockups in s_inodes iterators	2020-01-12 12:21:37 +01:00
eventfd.c	eventfd: track eventfd_signal() recursion depth	2020-02-11 04:35:37 -08:00
eventpoll.c	ep_create_wakeup_source(): dentry name can change under you...	2020-10-07 08:01:31 +02:00
exec.c	mm: fix exec activate_mm vs TLB shootdown and lazy tlb switching race	2020-11-05 11:43:13 +01:00
fcntl.c	fs: mark expected switch fall-throughs	2019-04-08 18:21:02 -05:00
fhandle.c	fs/handle.c - fix up kerneldoc	2019-08-07 21:51:47 -04:00
file.c	fix multiplication overflow in copy_fdtable()	2020-05-27 17:46:12 +02:00
file_table.c	vfs: Export flush_delayed_fput for use by knfsd.	2019-08-19 11:00:39 -04:00
filesystems.c	fs/filesystems.c: downgrade user-reachable WARN_ONCE() to pr_warn_once()	2020-04-17 10:50:21 +02:00
fs-writeback.c	writeback: Fix sync livelock due to b_dirty_time processing	2020-09-03 11:27:04 +02:00
fs_context.c	vfs: subtype handling moved to fuse	2019-09-06 21:28:49 +02:00
fs_parser.c	vfs: Make fs_parse() handle fs_param_is_fd-type params better	2019-09-12 21:06:14 -04:00
fs_pin.c	switch the remnants of releasing the mountpoint away from fs_pin	2019-07-16 22:52:37 -04:00
fs_struct.c	treewide: Add SPDX license identifier for missed files	2019-05-21 10:50:45 +02:00
fs_types.c	fs: common implementation of file type	2019-01-21 17:48:13 +01:00
fsopen.c	Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2019-07-19 10:42:02 -07:00
inode.c	futex: Fix inode life-time issue	2020-03-25 08:25:58 +01:00
internal.h	fs: move guard_bio_eod() after bio_set_op_attrs	2020-01-17 19:48:21 +01:00
io_uring.c	io_uring: Fix double list add in io_queue_async_work()	2020-10-14 10:32:57 +02:00
ioctl.c	compat_ioctl: add compat_ptr_ioctl()	2019-12-17 19:55:30 +01:00
libfs.c	libfs: fix infoleak in simple_attr_read()	2020-04-01 11:02:17 +02:00
locks.c	locks: reinstate locks_delete_block optimization	2020-03-25 08:25:41 +01:00
mbcache.c	treewide: Add SPDX license identifier for more missed files	2019-05-21 10:50:45 +02:00
mount.h	switch the remnants of releasing the mountpoint away from fs_pin	2019-07-16 22:52:37 -04:00
mpage.c	fs: move guard_bio_eod() after bio_set_op_attrs	2020-01-17 19:48:21 +01:00
namei.c	namei: only return -ECHILD from follow_dotdot_rcu()	2020-03-05 16:43:48 +01:00
namespace.c	fs/namespace.c: fix use-after-free of mount in mnt_warn_timestamp_expiry()	2019-10-16 23:15:09 -04:00
no-block.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152	2019-05-30 11:26:32 -07:00
nsfs.c	vfs: Convert nsfs to use the new mount API	2019-05-25 18:00:06 -04:00
open.c	cifs_atomic_open(): fix double-put on late allocation failure	2020-03-18 07:17:51 +01:00
pipe.c	vfs: Convert pipe to use the new mount API	2019-05-25 18:00:07 -04:00
pnode.c	propagate_one(): mnt_set_mountpoint() needs mount_lock	2020-05-02 08:48:44 +02:00
pnode.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 209	2019-05-30 11:29:53 -07:00
posix_acl.c	treewide: Add SPDX license identifier for missed files	2019-05-21 10:50:45 +02:00
proc_namespace.c	vfs: subtype handling moved to fuse	2019-09-06 21:28:49 +02:00
read_write.c	fs: allow deduplication of eof block into the end of the destination file	2020-02-11 04:35:23 -08:00
readdir.c	readdir: be more conservative with directory entry names	2020-01-29 16:45:31 +01:00
select.c	fs/select.c: use struct_size() in kmalloc()	2019-07-16 19:23:25 -07:00
seq_file.c	seq_file: fix problem when seeking mid-record	2019-08-13 16:06:52 -07:00
signalfd.c	fs/signalfd.c: fix inconsistent return codes for signalfd4	2020-08-26 10:40:58 +02:00
splice.c	splice: only read in as much information as there is pipe buffer space	2019-12-17 19:56:52 +01:00
stack.c	treewide: Add SPDX license identifier for missed files	2019-05-21 10:50:45 +02:00
stat.c	fs: move generic stat response attr handling to vfs_getattr_nosec	2019-02-01 01:55:45 -05:00
statfs.c	vfs: Fix EOVERFLOW testing in put_compat_statfs64	2019-10-03 14:21:35 -07:00
super.c	vfs: remove lockdep bogosity in __sb_start_write	2020-11-24 13:29:01 +01:00
sync.c	fs/sync.c: sync_file_range(2) may use WB_SYNC_ALL writeback	2019-05-14 09:47:50 -07:00
timerfd.c	timerfd: Prepare for PREEMPT_RT	2019-08-01 20:51:23 +02:00
userfaultfd.c	userfaultfd: require CAP_SYS_PTRACE for UFFD_FEATURE_EVENT_FORK	2020-01-04 19:18:32 +01:00
utimes.c	utimes: Clamp the timestamps in notify_change()	2020-02-11 04:35:12 -08:00
xattr.c	xattr: break delegations in {set,remove}xattr	2020-08-11 15:33:39 +02:00