Theodore Ts'o f4a01017d6 ext4: Fix potential reclaim deadlock when truncating partial block ...

The ext4_block_truncate_page() function previously called
grab_cache_page(), which called find_or_create_page() with the
__GFP_FS flag potentially set.  This could cause a deadlock if the
system is low on memory and it attempts a memory reclaim, which could
potentially call back into ext4.  So we need to call
find_or_create_page() directly, and remove the __GFP_FP flag to avoid
this potential deadlock.

Thanks to Roland Dreier for reporting a lockdep warning which showed
this problem.

[20786.363249] =================================
[20786.363257] [ INFO: inconsistent lock state ]
[20786.363265] 2.6.31-2-generic #14~rbd4gitd960eea9
[20786.363270] ---------------------------------
[20786.363276] inconsistent {IN-RECLAIM_FS-W} -> {RECLAIM_FS-ON-W} usage.
[20786.363285] http/8397 [HC0[0]:SC0[0]:HE1:SE1] takes:
[20786.363291]  (jbd2_handle){+.+.?.}, at: [<ffffffff812008bb>] jbd2_journal_start+0xdb/0x150
[20786.363314] {IN-RECLAIM_FS-W} state was registered at:
[20786.363320]   [<ffffffff8108bef6>] mark_irqflags+0xc6/0x1a0
[20786.363334]   [<ffffffff8108d347>] __lock_acquire+0x287/0x430
[20786.363345]   [<ffffffff8108d595>] lock_acquire+0xa5/0x150
[20786.363355]   [<ffffffff812008da>] jbd2_journal_start+0xfa/0x150
[20786.363365]   [<ffffffff811d98a8>] ext4_journal_start_sb+0x58/0x90
[20786.363377]   [<ffffffff811cce85>] ext4_delete_inode+0xc5/0x2c0
[20786.363389]   [<ffffffff81146fa3>] generic_delete_inode+0xd3/0x1a0
[20786.363401]   [<ffffffff81147095>] generic_drop_inode+0x25/0x30
[20786.363411]   [<ffffffff81145ce2>] iput+0x62/0x70
[20786.363420]   [<ffffffff81142878>] dentry_iput+0x98/0x110
[20786.363429]   [<ffffffff81142a00>] d_kill+0x50/0x80
[20786.363438]   [<ffffffff811444c5>] dput+0x95/0x180
[20786.363447]   [<ffffffff8120de4b>] ecryptfs_d_release+0x2b/0x70
[20786.363459]   [<ffffffff81142978>] d_free+0x28/0x60
[20786.363468]   [<ffffffff81142a18>] d_kill+0x68/0x80
[20786.363477]   [<ffffffff81142ad3>] prune_one_dentry+0xa3/0xc0
[20786.363487]   [<ffffffff81142d61>] __shrink_dcache_sb+0x271/0x290
[20786.363497]   [<ffffffff81142e89>] prune_dcache+0x109/0x1b0
[20786.363506]   [<ffffffff81142f6f>] shrink_dcache_memory+0x3f/0x50
[20786.363516]   [<ffffffff810f6d3d>] shrink_slab+0x12d/0x190
[20786.363527]   [<ffffffff810f97d7>] balance_pgdat+0x4d7/0x640
[20786.363537]   [<ffffffff810f9a57>] kswapd+0x117/0x170
[20786.363546]   [<ffffffff810773ce>] kthread+0x9e/0xb0
[20786.363558]   [<ffffffff8101430a>] child_rip+0xa/0x20
[20786.363569]   [<ffffffffffffffff>] 0xffffffffffffffff
[20786.363598] irq event stamp: 15997
[20786.363603] hardirqs last  enabled at (15997): [<ffffffff81125f9d>] kmem_cache_alloc+0xfd/0x1a0
[20786.363617] hardirqs last disabled at (15996): [<ffffffff81125f01>] kmem_cache_alloc+0x61/0x1a0
[20786.363628] softirqs last  enabled at (15966): [<ffffffff810631ea>] __do_softirq+0x14a/0x220
[20786.363641] softirqs last disabled at (15861): [<ffffffff8101440c>] call_softirq+0x1c/0x30
[20786.363651] 
[20786.363653] other info that might help us debug this:
[20786.363660] 3 locks held by http/8397:
[20786.363665]  #0:  (&sb->s_type->i_mutex_key#8){+.+.+.}, at: [<ffffffff8112ed24>] do_truncate+0x64/0x90
[20786.363685]  #1:  (&sb->s_type->i_alloc_sem_key#5){+++++.}, at: [<ffffffff81147f90>] notify_change+0x250/0x350
[20786.363707]  #2:  (jbd2_handle){+.+.?.}, at: [<ffffffff812008bb>] jbd2_journal_start+0xdb/0x150
[20786.363724] 
[20786.363726] stack backtrace:
[20786.363734] Pid: 8397, comm: http Tainted: G         C 2.6.31-2-generic #14~rbd4gitd960eea9
[20786.363741] Call Trace:
[20786.363752]  [<ffffffff8108ad7c>] print_usage_bug+0x18c/0x1a0
[20786.363763]  [<ffffffff8108b0c0>] ? check_usage_backwards+0x0/0xb0
[20786.363773]  [<ffffffff8108bad2>] mark_lock_irq+0xf2/0x280
[20786.363783]  [<ffffffff8108bd97>] mark_lock+0x137/0x1d0
[20786.363793]  [<ffffffff8108c03c>] mark_held_locks+0x6c/0xa0
[20786.363803]  [<ffffffff8108c11f>] lockdep_trace_alloc+0xaf/0xe0
[20786.363813]  [<ffffffff810efbac>] __alloc_pages_nodemask+0x7c/0x180
[20786.363824]  [<ffffffff810e9411>] ? find_get_page+0x91/0xf0
[20786.363835]  [<ffffffff8111d3b7>] alloc_pages_current+0x87/0xd0
[20786.363845]  [<ffffffff810e9827>] __page_cache_alloc+0x67/0x70
[20786.363856]  [<ffffffff810eb7df>] find_or_create_page+0x4f/0xb0
[20786.363867]  [<ffffffff811cb3be>] ext4_block_truncate_page+0x3e/0x460
[20786.363876]  [<ffffffff812008da>] ? jbd2_journal_start+0xfa/0x150
[20786.363885]  [<ffffffff812008bb>] ? jbd2_journal_start+0xdb/0x150
[20786.363895]  [<ffffffff811c6415>] ? ext4_meta_trans_blocks+0x75/0xf0
[20786.363905]  [<ffffffff811e8d8b>] ext4_ext_truncate+0x1bb/0x1e0
[20786.363916]  [<ffffffff811072c5>] ? unmap_mapping_range+0x75/0x290
[20786.363926]  [<ffffffff811ccc28>] ext4_truncate+0x498/0x630
[20786.363938]  [<ffffffff8129b4ce>] ? _raw_spin_unlock+0x5e/0xb0
[20786.363947]  [<ffffffff81107306>] ? unmap_mapping_range+0xb6/0x290
[20786.363957]  [<ffffffff8108c3ad>] ? trace_hardirqs_on+0xd/0x10
[20786.363966]  [<ffffffff811ffe58>] ? jbd2_journal_stop+0x1f8/0x2e0
[20786.363976]  [<ffffffff81107690>] vmtruncate+0xb0/0x110
[20786.363986]  [<ffffffff81147c05>] inode_setattr+0x35/0x170
[20786.363995]  [<ffffffff811c9906>] ext4_setattr+0x186/0x370
[20786.364005]  [<ffffffff81147eab>] notify_change+0x16b/0x350
[20786.364014]  [<ffffffff8112ed30>] do_truncate+0x70/0x90
[20786.364021]  [<ffffffff8112f48b>] T.657+0xeb/0x110
[20786.364021]  [<ffffffff8112f4be>] sys_ftruncate+0xe/0x10
[20786.364021]  [<ffffffff81013132>] system_call_fastpath+0x16/0x1b

Reported-by: Roland Dreier <roland@digitalvampire.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

2009-07-05 22:08:16 -04:00

..

9p

9P doesn't need BKL in ->umount_begin()

2009-06-17 00:36:36 -04:00

adfs

Cleanup of adfs headers

2009-06-17 00:36:36 -04:00

affs

affs: add ->sync_fs

2009-06-11 21:36:14 -04:00

afs

AFS: Fix lock imbalance

2009-06-30 13:30:44 -07:00

autofs

switch follow_down()

2009-06-11 21:36:01 -04:00

autofs4

switch follow_down()

2009-06-11 21:36:01 -04:00

befs

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6

2009-06-17 08:46:57 -07:00

bfs

bfs: add ->sync_fs

2009-06-11 21:36:14 -04:00

btrfs

Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable

2009-07-02 16:52:38 -07:00

cachefiles

enforce ->sync_fs is only called for rw superblock

2009-06-11 21:36:06 -04:00

cifs

cifs: fix fh_mutex locking in cifs_reopen_file

2009-06-27 23:46:43 +00:00

coda

splice: implement default splice_read method

2009-05-11 14:13:10 +02:00

configfs

configfs: Rework configfs_depend_item() locking and make lockdep happy

2009-04-30 10:48:26 -07:00

cramfs

fs/cramfs: return f_fsid for statfs(2)

2009-04-02 19:05:08 -07:00

debugfs

debugfs: use specified mode to possibly mark files read/write only

2009-06-15 21:30:28 -07:00

devpts

devpts: remove module-related code

2009-06-24 08:15:24 -04:00

dlm

dlm: use more NOFS allocation

2009-05-15 11:24:59 -05:00

ecryptfs

push BKL down into ->put_super

2009-06-11 21:36:07 -04:00

efs

get rid of BKL in fs/efs

2009-06-17 00:36:36 -04:00

exofs

[SCSI] Merge branch 'linus'

2009-06-12 10:02:03 -05:00

exportfs

Merge branch 'next' into for-linus

2008-12-25 11:40:09 +11:00

ext2

ext2: return -EIO not -ESTALE on directory traversal through deleted inode

2009-06-30 18:56:00 -07:00

ext3

helpers for acl caching + switch to those

2009-06-24 08:17:07 -04:00

ext4

ext4: Fix potential reclaim deadlock when truncating partial block

2009-07-05 22:08:16 -04:00

fat

fat: Fix the removal of opts->fs_dmask

2009-06-20 21:50:47 +09:00

freevxfs

push BKL down into ->put_super

2009-06-11 21:36:07 -04:00

fscache

FS-Cache: Fixup renamed filenames in comments in internal.h

2009-05-27 10:20:13 -07:00

fuse

fuse: invalidation reverse calls

2009-06-30 20:12:24 +02:00

gfs2

block: rename CONFIG_LBD to CONFIG_LBDAF

2009-06-19 08:08:50 +02:00

hfs

hfs: add ->sync_fs

2009-06-11 21:36:15 -04:00

hfsplus

hfsplus: add ->sync_fs

2009-06-11 21:36:16 -04:00

hostfs

hostfs: set maximum filesize in superblock for proper LFS support

2009-06-30 18:56:03 -07:00

hpfs

Push BKL down into ->remount_fs()

2009-06-11 21:36:11 -04:00

hppfs

hppfs: hppfs_read_file() may return -ERROR

2009-04-02 19:04:53 -07:00

hugetlbfs

Merge branch 'master' into next

2009-05-22 18:40:59 +10:00

isofs

isofs: cleanup mount option processing

2009-06-18 13:03:45 -07:00

jbd

jbd: clean up journal_try_to_free_buffers()

2009-06-18 13:03:45 -07:00

jbd2

jbd2: Remove GFP_ATOMIC kmalloc from inside spinlock critical region

2009-06-20 23:34:44 -04:00

jffs2

Merge git://git.infradead.org/mtd-2.6

2009-07-01 11:25:46 -07:00

jfs

another race fix in jfs_check_acl()

2009-06-24 17:02:42 -04:00

lockd

Merge branch 'for-2.6.31' of git://fieldses.org/git/linux-nfsd

2009-06-22 12:55:50 -07:00

minix

Making fs/minix/minix.h double including safe

2009-06-22 11:34:42 -07:00

ncpfs

NLS: update handling of Unicode

2009-06-15 21:44:43 -07:00

nfs

NFS: Correct the NFS mount path when following a referral

2009-06-22 21:28:25 -07:00

nfs_common

SUNRPC: nfsacl_encode/nfsacl_decode should be exported as GPL-only

2008-12-23 15:21:32 -05:00

nfsd

NFSD: Don't hold unrefcounted creds over call to nfsd_setuser()

2009-07-03 10:21:10 -04:00

nilfs2

switch nilfs2 to inode->i_acl

2009-06-24 08:17:05 -04:00

nls

NLS: update handling of Unicode

2009-06-15 21:44:43 -07:00

notify

fs/notify/inotify: decrement user inotify count on close

2009-07-02 08:23:00 -04:00

ntfs

ntfs: use is_power_of_2() function for clarity.

2009-06-16 19:47:48 -07:00

ocfs2

Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2

2009-06-23 19:36:02 -07:00

omfs

switch omfs to simple_fsync()

2009-06-11 21:36:13 -04:00

openpromfs

zero i_uid/i_gid on inode allocation

2009-01-05 11:54:28 -05:00

partitions

Merge branch 'for-2.6.31' of git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6

2009-06-12 09:29:42 -07:00

proc

proc: vmcore - use kzalloc in get_new_element()

2009-06-18 13:03:41 -07:00

qnx4

fs/qnx4: sanitize includes

2009-06-11 21:36:12 -04:00

quota

quota: cleanup dquota sync functions (version 4)

2009-06-11 21:36:04 -04:00

ramfs

ramfs: ignore unknown mount options

2009-06-14 17:58:25 -07:00

reiserfs

helpers for acl caching + switch to those

2009-06-24 08:17:07 -04:00

romfs

ROMFS: romfs_dev_read() error ignored

2009-05-09 10:49:41 -04:00

smbfs

push BKL down into ->put_super

2009-06-11 21:36:07 -04:00

squashfs

push BKL down into ->put_super

2009-06-11 21:36:07 -04:00

sysfs

Sysfs: fix possible memleak in sysfs_follow_link

2009-06-15 21:30:23 -07:00

sysv

get rid of BKL in fs/sysv

2009-06-17 00:36:37 -04:00

ubifs

helpers for acl caching + switch to those

2009-06-24 08:17:07 -04:00

udf

udf: remove redundant tests on unsigned

2009-06-24 13:48:28 +02:00

ufs

ufs: sector_t cannot be negative

2009-06-18 13:03:46 -07:00

xfs

switch xfs to generic acl caching helpers

2009-06-24 08:17:07 -04:00

aio.c

eventfd: revised interface and cleanups

2009-06-30 18:55:58 -07:00

anon_inodes.c

fs: Provide empty .set_page_dirty() aop for anon inodes

2009-06-18 14:46:10 +02:00

attr.c

vfs: Use lowercase names of quota functions

2009-03-26 02:18:35 +01:00

bad_inode.c

kill ->dir_notify()

2008-12-31 18:07:43 -05:00

binfmt_aout.c

sanitize ifdefs in binfmt_aout

2009-01-03 11:45:54 -08:00

binfmt_elf_fdpic.c

elf_core_dump: use rcu_read_lock() to access ->real_parent

2009-06-18 13:03:52 -07:00

binfmt_elf.c

elf: fix one check-after-use

2009-07-01 11:14:28 -07:00

binfmt_em86.c

Allow recursion in binfmt_script and binfmt_misc

2008-10-16 11:21:38 -07:00

binfmt_flat.c

flat: fix data sections alignment

2009-05-29 08:40:02 -07:00

binfmt_misc.c

fs/binfmt_misc.c: add terminating newline to /proc/sys/fs/binfmt_misc/status

2009-01-06 15:59:19 -08:00

binfmt_script.c

Allow recursion in binfmt_script and binfmt_misc

2008-10-16 11:21:38 -07:00

binfmt_som.c

Don't crap into descriptor table in binfmt_som

2009-03-31 23:00:28 -04:00

bio-integrity.c

block: Create bip slabs with embedded integrity vectors

2009-07-01 10:56:25 +02:00

bio.c

block: Create bip slabs with embedded integrity vectors

2009-07-01 10:56:25 +02:00

block_dev.c

vfs: Rename fsync_super() to sync_filesystem() (version 4)

2009-06-11 21:36:04 -04:00

buffer.c

Merge branch 'for-2.6.31' of git://git.kernel.dk/linux-2.6-block

2009-06-11 11:10:35 -07:00

char_dev.c

fs: Remove i_cindex from struct inode

2009-06-11 21:36:09 -04:00

compat_binfmt_elf.c

…

compat_ioctl.c

fs: Add new pre-allocation ioctls to vfs for compatibility with legacy xfs ioctls

2009-06-24 08:15:27 -04:00

compat.c

trivial: fix comment typo in fs/compat.c

2009-06-12 18:01:44 +02:00

dcache.c

dcache: extrace and use d_unlinked()

2009-06-11 21:36:06 -04:00

dcookies.c

[CVE-2009-0029] System call wrapper special cases

2009-01-14 14:15:18 +01:00

direct-io.c

block: Do away with the notion of hardsect_size

2009-05-22 23:22:54 +02:00

drop_caches.c

mm: remove __invalidate_mapping_pages variant

2009-06-16 19:47:43 -07:00

eventfd.c

eventfd: revised interface and cleanups

2009-06-30 18:55:58 -07:00

eventpoll.c

epoll: fix nested calls support

2009-06-18 13:03:41 -07:00

exec.c

Merge branch 'perfcounters-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2009-06-11 14:01:07 -07:00

fcntl.c

send_sigio_to_task: sanitize the usage of fown->signum

2009-06-16 15:36:17 -07:00

fifo.c

[PATCH] introduce fmode_t, do annotations

2008-10-21 07:47:06 -04:00

file_table.c

fs: move mark_files_ro into file_table.c

2009-06-11 21:36:02 -04:00

file.c

…

filesystems.c

fs: Mark get_filesystem_list() as __init function.

2009-04-20 23:02:52 -04:00

fs_struct.c

Get rid of indirect include of fs_struct.h

2009-03-31 23:00:27 -04:00

fs-writeback.c

cleanup __writeback_single_inode

2009-06-24 08:15:26 -04:00

generic_acl.c

New helper - current_umask()

2009-03-31 23:00:26 -04:00

inode.c

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6

2009-06-24 10:03:12 -07:00

internal.h

Trim a bit of crap from fs.h

2009-06-11 21:36:07 -04:00

ioctl.c

fs: Add new pre-allocation ioctls to vfs for compatibility with legacy xfs ioctls

2009-06-24 08:15:27 -04:00

ioprio.c

[CVE-2009-0029] System call wrappers part 28

2009-01-14 14:15:30 +01:00

Kconfig

Merge branch 'for-2.6.31' of git://fieldses.org/git/linux-nfsd

2009-06-22 12:55:50 -07:00

Kconfig.binfmt

CORE_DUMP_DEFAULT_ELF_HEADERS depends on ELF_CORE

2009-01-09 16:54:41 -08:00

libfs.c

New helper - simple_fsync()

2009-06-11 21:36:11 -04:00

locks.c

lockd: call locks_release_private to cleanup per-filesystem state

2009-04-24 16:36:03 -04:00

Makefile

nilfs2: update makefile and Kconfig

2009-04-07 08:31:16 -07:00

mbcache.c

…

mpage.c

ext4: Properly initialize the buffer_head state

2009-05-13 15:13:42 -04:00

namei.c

integrity: add ima_counts_put (updated)

2009-06-29 08:59:10 +10:00

namespace.c

... and the same for vfsmount id/mount group id

2009-06-24 08:15:26 -04:00

nfsctl.c

[CVE-2009-0029] System call wrappers part 27

2009-01-14 14:15:29 +01:00

no-block.c

…

open.c

fs: Add new pre-allocation ioctls to vfs for compatibility with legacy xfs ioctls

2009-06-24 08:15:27 -04:00

pipe.c

splice: implement default splice_read method

2009-05-11 14:13:10 +02:00

pnode.c

…

pnode.h

…

posix_acl.c

CRED: Wrap task credential accesses in the filesystem subsystem

2008-11-14 10:39:05 +11:00

read_write.c

splice: implement default splice_read method

2009-05-11 14:13:10 +02:00

read_write.h

…

readdir.c

[CVE-2009-0029] System call wrappers part 32

2009-01-14 14:15:31 +01:00

select.c

poll: avoid extra wakeups in select/poll

2009-06-16 19:47:48 -07:00

seq_file.c

seq_file: add function to write binary data

2009-06-18 13:03:57 -07:00

signalfd.c

[CVE-2009-0029] System call wrappers part 31

2009-01-14 14:15:31 +01:00

splice.c

splice: fix kmaps in default_file_splice_write()

2009-05-19 11:37:46 +02:00

stack.c

…

stat.c

kill vfs_stat_fd / vfs_lstat_fd

2009-04-20 23:02:52 -04:00

super.c

... and the same for vfsmount id/mount group id

2009-06-24 08:15:26 -04:00

sync.c

remove the call to ->write_super in __sync_filesystem

2009-06-11 21:36:17 -04:00

timerfd.c

timerfd: add flags check

2009-02-18 15:37:53 -08:00

utimes.c

[CVE-2009-0029] System call wrappers part 30

2009-01-14 14:15:30 +01:00

xattr_acl.c

…

xattr.c

fs: introduce mnt_clone_write

2009-06-11 21:36:02 -04:00