kernel_optimize_test/fs
Thomas Betker 5ffd3412ae jffs2: Fix lock acquisition order bug in jffs2_write_begin
jffs2_write_begin() first acquires the page lock, then f->sem. This
causes an AB-BA deadlock with jffs2_garbage_collect_live(), which first
acquires f->sem, then the page lock:

jffs2_garbage_collect_live
    mutex_lock(&f->sem)                         (A)
    jffs2_garbage_collect_dnode
        jffs2_gc_fetch_page
            read_cache_page_async
                do_read_cache_page
                    lock_page(page)             (B)

jffs2_write_begin
    grab_cache_page_write_begin
        find_lock_page
            lock_page(page)                     (B)
    mutex_lock(&f->sem)                         (A)

We fix this by restructuring jffs2_write_begin() to take f->sem before
the page lock. However, we make sure that f->sem is not held when
calling jffs2_reserve_space(), as this is not permitted by the locking
rules.

The deadlock above was observed multiple times on an SoC with a dual
ARMv7 (Cortex-A9), running the long-term 3.4.11 kernel; it occurred
when using scp to copy files from a host system to the ARM target
system. The fix was heavily tested on the same target system.

Cc: stable@vger.kernel.org
Signed-off-by: Thomas Betker <thomas.betker@rohde-schwarz.com>
Acked-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-11-09 17:02:50 +02:00
..
9p
adfs
affs
afs
autofs4
befs
bfs
btrfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2012-10-26 09:34:04 -07:00
cachefiles
ceph Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client 2012-10-29 08:49:25 -07:00
cifs
coda
configfs
cramfs
debugfs
devpts
dlm
ecryptfs
efs
exofs
exportfs
ext2
ext3 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs 2012-10-16 18:12:38 -07:00
ext4 ext4: fix unjournaled inode bitmap modification 2012-10-28 22:24:57 -04:00
fat
freevxfs
fscache
fuse
gfs2
hfs
hfsplus
hostfs
hpfs
hppfs
hugetlbfs
isofs
jbd
jbd2
jffs2 jffs2: Fix lock acquisition order bug in jffs2_write_begin 2012-11-09 17:02:50 +02:00
jfs jfs: Fix FITRIM argument handling 2012-10-17 09:18:38 -05:00
lockd LOCKD: Clear ln->nsm_clnt only when ln->nsm_users is zero 2012-10-24 10:46:22 -04:00
logfs
minix
ncpfs
nfs NFS4: nfs4_opendata_access should return errno 2012-11-02 18:51:54 -04:00
nfs_common
nfsd
nilfs2
nls
notify
ntfs
ocfs2
omfs
openpromfs
proc Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-10-24 04:07:02 +03:00
pstore
qnx4
qnx6
quota Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs 2012-10-16 18:12:38 -07:00
ramfs
reiserfs
romfs
squashfs
sysfs sysfs: sysfs_pathname/sysfs_add_one: Use strlcat() instead of strcat() 2012-10-24 15:57:14 -07:00
sysv
ubifs
udf
ufs
xfs
aio.c
anon_inodes.c
attr.c
bad_inode.c
binfmt_aout.c
binfmt_elf_fdpic.c
binfmt_elf.c
binfmt_em86.c
binfmt_flat.c
binfmt_misc.c
binfmt_script.c
binfmt_som.c
bio-integrity.c
bio.c vfs: fix: don't increase bio_slab_max if krealloc() fails 2012-10-22 22:00:26 +02:00
block_dev.c Lock splice_read and splice_write functions 2012-10-28 10:59:37 -07:00
buffer.c
char_dev.c char_dev: pin parent kobject 2012-10-22 08:50:37 +03:00
compat_binfmt_elf.c
compat_ioctl.c fs/compat_ioctl.c: VIDEO_SET_SPU_PALETTE missing error check 2012-10-25 14:37:53 -07:00
compat.c
coredump.c
coredump.h
dcache.c
dcookies.c
direct-io.c
drop_caches.c
eventfd.c
eventpoll.c
exec.c freezer: exec should clear PF_NOFREEZE along with PF_KTHREAD 2012-10-25 22:28:12 +02:00
fcntl.c
fhandle.c
fifo.c
file_table.c
file.c Return the right error value when dup[23]() newfd argument is too large 2012-10-30 21:27:28 -07:00
filesystems.c
fs_struct.c
fs-writeback.c
generic_acl.c
inode.c
internal.h
ioctl.c
ioprio.c
Kconfig
Kconfig.binfmt
libfs.c
locks.c
Makefile
mbcache.c
mount.h
mpage.c
namei.c VFS: don't do protected {sym,hard}links by default 2012-10-26 10:05:07 -07:00
namespace.c
no-block.c
open.c
pipe.c
pnode.c
pnode.h
posix_acl.c
proc_namespace.c
read_write.c
read_write.h
readdir.c
select.c
seq_file.c
signalfd.c
splice.c
stack.c
stat.c
statfs.c
super.c
sync.c
timerfd.c
utimes.c
xattr_acl.c
xattr.c fs, xattr: fix bug when removing a name not in xattr list 2012-10-18 12:35:58 -07:00