android_kernel_xiaomi_sm8350/fs
Ian Kent 1864f7bd58 autofs4: deadlock during create
Due to inconsistent locking in the VFS between calls to lookup and
revalidate deadlock can occur in the automounter.

The inconsistency is that the directory inode mutex is held for both lookup
and revalidate calls when called via lookup_hash whereas it is held only
for lookup during a path walk.  Consequently, if the mutex is held during a
call to revalidate autofs4 can't release the mutex to callback the daemon
as it can't know whether it owns the mutex.

This situation happens when a process tries to create a directory within an
automount and a second process also tries to create the same directory
between the lookup and the mkdir.  Since the first process has dropped the
mutex for the daemon callback, the second process takes it during
revalidate leading to deadlock between the autofs daemon and the second
process when the daemon tries to create the mount point directory.

After spending quite a bit of time trying to resolve this on more than one
occassion, using rather complex and ulgy approaches, it turns out that just
delaying the hashing of the dentry until the create operation works fine.

Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-08-22 19:52:46 -07:00
..
9p 9p: fix debug compilation error 2007-07-16 16:03:25 -05:00
adfs mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
affs mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
afs AFS: fix file locking 2007-07-31 15:39:40 -07:00
autofs
autofs4 autofs4: deadlock during create 2007-08-22 19:52:46 -07:00
befs mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
bfs mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
cifs [CIFS] Check return code on failed alloc 2007-08-18 00:15:20 +00:00
coda coda: remove CODA_STORE/CODA_RELEASE upcalls 2007-07-21 17:49:14 -07:00
configfs mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
cramfs
debugfs debugfs: remove rmdir() non-empty complaint 2007-07-18 15:49:48 -07:00
devpts
dlm [DLM] fix basts for granted PR waiting CW 2007-08-14 10:31:02 +01:00
ecryptfs eCryptfs: fix lookup error for special files 2007-08-22 19:52:44 -07:00
efs mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
exportfs knfsd: exportfs: split out reconnecting a dentry from find_exported_dentry 2007-07-17 10:23:06 -07:00
ext2 fix inode_table test in ext234_check_descriptors 2007-07-26 11:35:17 -07:00
ext3 fix inode_table test in ext234_check_descriptors 2007-07-26 11:35:17 -07:00
ext4 "ext4_ext_put_in_cache" uses __u32 to receive physical block number 2007-07-31 15:39:37 -07:00
fat mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
freevxfs mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
fuse mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
gfs2 [GFS2] Revert remounting w/o acl option leaves acls enabled 2007-08-14 10:34:40 +01:00
hfs mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
hfsplus mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
hostfs
hpfs mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
hppfs
hugetlbfs mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
isofs isofs: mounting to regular file may succeed 2007-07-31 15:39:41 -07:00
jbd mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
jbd2 mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
jffs2 JFFS2 locking regression fix. 2007-08-20 22:44:27 -07:00
jfs mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
lockd lockd and nfsd endianness annotation fixes 2007-07-26 11:11:56 -07:00
minix mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
msdos
ncpfs NCP: delete test of long-deceased CONFIG_NCPFS_DEBUGDENTRY 2007-07-31 15:39:41 -07:00
nfs NFS: Replace flush_scheduled_work with cancel_work_sync() and friends 2007-08-07 16:12:50 -04:00
nfs_common
nfsd knfsd: eliminate unnecessary -ENOENT returns on export downcalls 2007-07-31 15:39:38 -07:00
nls
ntfs mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
ocfs2 ocfs2: set non-default s_time_gran during mount 2007-08-09 17:27:58 -07:00
openpromfs mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
partitions [PARTITION]: Sun/Solaris VTOC table corrections 2007-07-30 00:27:31 -07:00
proc Fix leaks on /proc/{*/sched,sched_debug,timer_list,timer_stats} 2007-07-31 15:39:40 -07:00
qnx4 mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
ramfs NOMMU: Fix SYSV IPC SHM 2007-07-31 15:39:36 -07:00
reiserfs more reiserfs endianness annotations 2007-07-26 11:11:58 -07:00
romfs mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
smbfs mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
sysfs mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
sysv mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
udf UDF: fix UID and GID mount option ignorance 2007-07-31 15:39:43 -07:00
ufs mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
vfat
xfs xfs ioctl __user annotations 2007-07-26 11:11:57 -07:00
aio.c
anon_inodes.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm 2007-07-17 11:50:26 -07:00
attr.c Introduce is_owner_or_cap() to wrap CAP_FOWNER use with fsuid check 2007-07-17 12:00:03 -07:00
bad_inode.c
binfmt_aout.c
binfmt_elf_fdpic.c coredump masking: ELF-FDPIC: enable core dump filtering 2007-07-19 10:04:47 -07:00
binfmt_elf.c revert "PIE randomization" 2007-07-21 17:49:14 -07:00
binfmt_em86.c
binfmt_flat.c
binfmt_misc.c mm: variable length argument support 2007-07-19 10:04:45 -07:00
binfmt_script.c mm: variable length argument support 2007-07-19 10:04:45 -07:00
binfmt_som.c
bio.c [BLOCK] Get rid of request_queue_t typedef 2007-07-24 09:28:11 +02:00
block_dev.c mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
buffer.c fix some conversion overflows 2007-07-20 08:44:19 -07:00
char_dev.c unregister_chrdev() return void 2007-07-19 10:04:43 -07:00
compat_ioctl.c [PATCH] remove duplicated ioctl entries in compat_ioctl.c 2007-08-06 15:06:03 -04:00
compat.c mm: variable length argument support 2007-07-19 10:04:45 -07:00
dcache.c mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
dcookies.c Remove fs.h from mm.h 2007-07-29 17:09:29 -07:00
direct-io.c dio: zero struct dio with kzalloc instead of manually 2007-08-20 22:50:25 -07:00
dnotify.c mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
dquot.c mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
drop_caches.c
eventfd.c
eventpoll.c mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
exec.c signalfd: make it group-wide, fix posix-timers scheduling 2007-08-22 19:52:46 -07:00
fcntl.c mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
fifo.c
file_table.c
file.c
filesystems.c
fs-writeback.c
generic_acl.c Introduce is_owner_or_cap() to wrap CAP_FOWNER use with fsuid check 2007-07-17 12:00:03 -07:00
inode.c mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
inotify_user.c mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
inotify.c
internal.h
ioctl.c
ioprio.c
Kconfig NFSD/SUNRPC: Fix the automatic selection of RPCSEC_GSS 2007-07-19 15:09:02 -04:00
Kconfig.binfmt
libfs.c
locks.c rename setlease to generic_setlease 2007-07-31 15:39:43 -07:00
Makefile
mbcache.c mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
mpage.c
namei.c fs: remove path_walk export 2007-07-19 10:04:45 -07:00
namespace.c mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
nfsctl.c nfsctl: use vfs_path_lookup 2007-07-19 10:04:45 -07:00
no-block.c
open.c VFS: fix a race in lease-breaking during truncate 2007-07-31 15:39:42 -07:00
pipe.c docbook: add pipes, other fixes 2007-07-27 08:08:51 +02:00
pnode.c
pnode.h
posix_acl.c
quota_v1.c
quota_v2.c
quota.c [IA64] Fix build failure in fs/quota.c 2007-07-27 15:40:13 -07:00
read_write.c
read_write.h
readdir.c
select.c
seq_file.c
signalfd.c signalfd: make it group-wide, fix posix-timers scheduling 2007-08-22 19:52:46 -07:00
splice.c docbook: add pipes, other fixes 2007-07-27 08:08:51 +02:00
stack.c
stat.c
super.c
sync.c
timerfd.c make timerfd return a u64 and fix the __put_user 2007-07-26 11:35:17 -07:00
utimes.c Introduce is_owner_or_cap() to wrap CAP_FOWNER use with fsuid check 2007-07-17 12:00:03 -07:00
xattr_acl.c
xattr.c Introduce is_owner_or_cap() to wrap CAP_FOWNER use with fsuid check 2007-07-17 12:00:03 -07:00