David Howells 5a039c3227 afs: Make afs_write_begin() avoid writing to a page that's being stored ... Make afs_write_begin() wait for a page that's marked PG_writeback because: (1) We need to avoid interference with the data being stored so that the data on the server ends up in a defined state. (2) page->private is used to track the window of dirty data within a page, but it's also used by the storage code to track what's being written, being cleared by the completion notification. Ownership can't be relinquished by the storage code until completion because it a store fails, the data must be remarked dirty. Tracing shows something like the following (edited): x86_64-linux-gn-15940 [1] afs_page_dirty: vn=ffff8800bef33800 9c75 begin 0-125 kworker/u8:3-114 [2] afs_page_dirty: vn=ffff8800bef33800 9c75 store+ 0-125 x86_64-linux-gn-15940 [1] afs_page_dirty: vn=ffff8800bef33800 9c75 begin 0-2052 kworker/u8:3-114 [2] afs_page_dirty: vn=ffff8800bef33800 9c75 clear 0-2052 kworker/u8:3-114 [2] afs_page_dirty: vn=ffff8800bef33800 9c75 store 0-0 kworker/u8:3-114 [2] afs_page_dirty: vn=ffff8800bef33800 9c75 WARN 0-0 The clear (completion) corresponding to the store+ (store continuation from a previous page) happens between the second begin (afs_write_begin) and the store corresponding to that. This results in the second store not seeing any data to write back, leading to the following warning: WARNING: CPU: 2 PID: 114 at ../fs/afs/write.c:403 afs_write_back_from_locked_page+0x19d/0x76c [kafs] Modules linked in: kafs(E) CPU: 2 PID: 114 Comm: kworker/u8:3 Tainted: G E 4.14.0-fscache+ #242 Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014 Workqueue: writeback wb_workfn (flush-afs-2) task: ffff8800cad72600 task.stack: ffff8800cad44000 RIP: 0010:afs_write_back_from_locked_page+0x19d/0x76c [kafs] RSP: 0018:ffff8800cad47aa0 EFLAGS: 00010246 RAX: 0000000000000001 RBX: ffff8800bef33a20 RCX: 0000000000000000 RDX: 000000000000000f RSI: ffffffff81c5d0e0 RDI: ffff8800cad72e78 RBP: ffff8800d31ea1e8 R08: ffff8800c1358000 R09: ffff8800ca00e400 R10: ffff8800cad47a38 R11: ffff8800c5d9e400 R12: 0000000000000000 R13: ffffea0002d9df00 R14: ffffffffa0023c1c R15: 0000000000007fdf FS: 0000000000000000(0000) GS:ffff8800ca700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f85ac6c4000 CR3: 0000000001c10001 CR4: 00000000001606e0 Call Trace: ? clear_page_dirty_for_io+0x23a/0x267 afs_writepages_region+0x1be/0x286 [kafs] afs_writepages+0x60/0x127 [kafs] do_writepages+0x36/0x70 __writeback_single_inode+0x12f/0x635 writeback_sb_inodes+0x2cc/0x452 __writeback_inodes_wb+0x68/0x9f wb_writeback+0x208/0x470 ? wb_workfn+0x22b/0x565 wb_workfn+0x22b/0x565 ? worker_thread+0x230/0x2ac process_one_work+0x2cc/0x517 ? worker_thread+0x230/0x2ac worker_thread+0x1d4/0x2ac ? rescuer_thread+0x29b/0x29b kthread+0x15d/0x165 ? kthread_create_on_node+0x3f/0x3f ? call_usermodehelper_exec_async+0x118/0x11f ret_from_fork+0x24/0x30 Signed-off-by: David Howells <dhowells@redhat.com>		2017-11-24 10:56:51 +00:00
..
9p	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
adfs	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
affs	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
afs	afs: Make afs_write_begin() avoid writing to a page that's being stored	2017-11-24 10:56:51 +00:00
autofs4	Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2017-09-14 18:13:32 -07:00
befs	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
bfs	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
btrfs	AFS development	2017-11-16 11:41:22 -08:00
cachefiles	mm: remove __GFP_COLD	2017-11-15 18:21:06 -08:00
ceph	mm, pagevec: remove cold parameter for pagevecs	2017-11-15 18:21:06 -08:00
cifs	cifs: use find_get_pages_range_tag()	2017-11-15 18:21:04 -08:00
coda	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
configfs	configfs: make ci_type field, some pointers and function arguments const	2017-10-19 16:15:16 +02:00
cramfs	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
crypto	fscrypt: lots of cleanups, mostly courtesy by Eric Biggers	2017-11-14 11:35:15 -08:00
debugfs	debugfs: Remove redundant license text	2017-11-07 20:25:03 +01:00
devpts	pty: Repair TIOCGPTPEER	2017-08-24 13:23:03 -07:00
dlm	A couple of configfs cleanups:	2017-11-14 14:44:04 -08:00
ecryptfs	slab, slub, slob: add slab_flags_t	2017-11-15 18:21:01 -08:00
efivarfs	VFS: Kill off s_options and helpers	2017-07-11 06:09:21 -04:00
efs	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
exofs	Merge branch 'for-4.14/block' of git://git.kernel.dk/linux-block	2017-09-07 11:59:42 -07:00
exportfs
ext2	Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs	2017-11-14 14:13:11 -08:00
ext4	mm, pagevec: remove cold parameter for pagevecs	2017-11-15 18:21:06 -08:00
f2fs	f2fs-for-4.15-rc1	2017-11-16 12:10:21 -08:00
fat	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
freevxfs
fscache	AFS development	2017-11-16 11:41:22 -08:00
fuse	Merge branch 'akpm' (patches from Andrew)	2017-11-15 19:42:40 -08:00
gfs2	mm, pagevec: remove cold parameter for pagevecs	2017-11-15 18:21:06 -08:00
hfs	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
hfsplus	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
hostfs	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
hpfs	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
hugetlbfs	mm, pagevec: remove cold parameter for pagevecs	2017-11-15 18:21:06 -08:00
isofs	Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs	2017-11-14 14:13:11 -08:00
jbd2	jbd2: convert timers to use timer_setup()	2017-10-18 12:40:28 -04:00
jffs2	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
jfs	A couple small fixes for jfs	2017-11-14 13:53:18 -08:00
kernfs	Merge branch 'for-4.14/block' of git://git.kernel.dk/linux-block	2017-09-07 11:59:42 -07:00
lockd	Modules updates for v4.15	2017-11-15 13:46:33 -08:00
minix	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
ncpfs	Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2017-11-13 17:56:58 -08:00
nfs	AFS development	2017-11-16 11:41:22 -08:00
nfs_common
nfsd	Add support for online resizing of file systems with bigalloc. Fix a	2017-11-14 12:59:42 -08:00
nilfs2	mm, pagevec: remove cold parameter for pagevecs	2017-11-15 18:21:06 -08:00
nls	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
notify	Merge branch 'for-linus' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/jikos/trivial	2017-11-15 10:14:11 -08:00
ntfs	Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block	2017-11-14 15:32:19 -08:00
ocfs2	AFS development	2017-11-16 11:41:22 -08:00
omfs	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
openpromfs
orangefs	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
overlayfs	Merge branch 'linus' into locking/core, to resolve conflicts	2017-11-07 10:32:44 +01:00
proc	mm: consolidate page table accounting	2017-11-15 18:21:04 -08:00
pstore	Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2017-11-13 17:56:58 -08:00
qnx4	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
qnx6	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
quota	Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs	2017-11-14 14:13:11 -08:00
ramfs	mm: make pagevec_lookup() update index	2017-09-06 17:27:26 -07:00
reiserfs	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
romfs	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
squashfs	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
sysfs
sysv	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
tracefs	VFS: Don't use save/replace_mount_options if not using generic_show_options	2017-07-06 03:31:46 -04:00
ubifs	fscrypt: lots of cleanups, mostly courtesy by Eric Biggers	2017-11-14 11:35:15 -08:00
udf	Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs	2017-11-14 14:13:11 -08:00
ufs	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
xfs	slab, slub, slob: add slab_flags_t	2017-11-15 18:21:01 -08:00
aio.c	locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()	2017-10-25 11:01:08 +02:00
anon_inodes.c
attr.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
bad_inode.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
binfmt_aout.c	fs: fix kernel_read prototype	2017-09-04 19:05:15 -04:00
binfmt_elf_fdpic.c	Merge branch 'fdpic' of http://git.linaro.org/people/nicolas.pitre/linux into devel-stable	2017-10-02 23:16:29 +01:00
binfmt_elf.c	Merge branch 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm	2017-11-16 12:50:35 -08:00
binfmt_em86.c
binfmt_flat.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
binfmt_misc.c	fs/binfmt_misc.c: node could be NULL when evicting inode	2017-10-13 16:18:33 -07:00
binfmt_script.c	exec: load_script: kill the onstack interp[BINPRM_BUF_SIZE] array	2017-10-03 17:54:25 -07:00
block_dev.c	Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block	2017-11-14 15:32:19 -08:00
buffer.c	mm, pagevec: remove cold parameter for pagevecs	2017-11-15 18:21:06 -08:00
char_dev.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
compat_binfmt_elf.c
compat_ioctl.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
compat.c
coredump.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
dax.c	mm, pagevec: remove cold parameter for pagevecs	2017-11-15 18:21:06 -08:00
dcache.c	kmemcheck: remove annotations	2017-11-15 18:21:04 -08:00
dcookies.c
direct-io.c	Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block	2017-11-14 15:32:19 -08:00
drop_caches.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
eventfd.c	There has been a fair amount of activity in the docs tree this time	2017-07-03 21:13:25 -07:00
eventpoll.c	fs/epoll: use faster rb_first_cached()	2017-09-08 18:26:49 -07:00
exec.c	locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()	2017-10-25 11:01:08 +02:00
fcntl.c	Merge branch 'linus' into locking/core, to resolve conflicts	2017-11-07 10:32:44 +01:00
fhandle.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
file_table.c	fs, mm: account filp cache to kmemcg	2017-11-15 18:21:04 -08:00
file.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
filesystems.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
fs_pin.c	Merge branch 'linus' into locking/core, to resolve conflicts	2017-11-07 10:32:44 +01:00
fs_struct.c
fs-writeback.c	writeback: merge try_to_writeback_inodes_sb_nr() into caller	2017-10-10 08:14:37 -06:00
inode.c	locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()	2017-10-25 11:01:08 +02:00
internal.h	Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs	2017-09-13 09:11:44 -07:00
ioctl.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
iomap.c	Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block	2017-11-14 15:32:19 -08:00
Kconfig	fs/Kconfig: kill CONFIG_PERCPU_RWSEM some more	2017-07-12 16:26:00 -07:00
Kconfig.binfmt	ARM: enable elf_fdpic on systems with an MMU	2017-09-10 19:31:46 -04:00
libfs.c	fs: convert __generic_file_fsync to use errseq_t based reporting	2017-07-06 07:02:29 -04:00
locks.c	locks: restore a warn for leaked locks on close	2017-07-21 13:57:31 -04:00
Makefile	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
mbcache.c	ext4: xattr inode deduplication	2017-06-22 11:44:55 -04:00
mount.h	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
mpage.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
namei.c	Merge branch 'linus' into locking/core, to resolve conflicts	2017-11-07 10:32:44 +01:00
namespace.c	vfs: fix mounting a filesystem with i_version	2017-11-08 15:16:36 -05:00
no-block.c
nsfs.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
open.c	ovl: don't allow writing ioctl on lower layer	2017-09-05 12:53:12 +02:00
pipe.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
pnode.c	mnt: Make propagate_umount less slow for overlapping mount propagation trees	2017-05-23 08:41:17 -05:00
pnode.h
posix_acl.c
proc_namespace.c	Merge branch 'linus' into locking/core, to resolve conflicts	2017-11-07 10:32:44 +01:00
read_write.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
readdir.c	Merge branch 'linus' into locking/core, to resolve conflicts	2017-11-07 10:32:44 +01:00
select.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
seq_file.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
signalfd.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
splice.c	locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()	2017-10-25 11:01:08 +02:00
stack.c
stat.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
statfs.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
super.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
sync.c	Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block	2017-11-14 15:32:19 -08:00
timerfd.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
userfaultfd.c	userfaultfd: use mmgrab instead of open-coded increment of mm_count	2017-11-15 18:21:05 -08:00
utimes.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
xattr.c	lsm: fix smack_inode_removexattr and xattr_getsecurity memleak	2017-10-04 18:03:15 +11:00