linux/fs
Peter Zijlstra 6946bd6363 [PATCH] lockdep: fix blkdev_open() warning
On Wed, 2006-08-09 at 07:57 +0200, Rolf Eike Beer wrote:
> =============================================
> [ INFO: possible recursive locking detected ]
> ---------------------------------------------
> parted/7929 is trying to acquire lock:
>  (&bdev->bd_mutex){--..}, at: [<c105eb8d>] __blkdev_put+0x1e/0x13c
>
> but task is already holding lock:
>  (&bdev->bd_mutex){--..}, at: [<c105eec6>] do_open+0x72/0x3a8
>
> other info that might help us debug this:
> 1 lock held by parted/7929:
>  #0:  (&bdev->bd_mutex){--..}, at: [<c105eec6>] do_open+0x72/0x3a8
> stack backtrace:
>  [<c1003aad>] show_trace_log_lvl+0x58/0x15b
>  [<c100495f>] show_trace+0xd/0x10
>  [<c1004979>] dump_stack+0x17/0x1a
>  [<c102dee5>] __lock_acquire+0x753/0x99c
>  [<c102e3b0>] lock_acquire+0x4a/0x6a
>  [<c1204501>] mutex_lock_nested+0xc8/0x20c
>  [<c105eb8d>] __blkdev_put+0x1e/0x13c
>  [<c105ecc4>] blkdev_put+0xa/0xc
>  [<c105f18a>] do_open+0x336/0x3a8
>  [<c105f21b>] blkdev_open+0x1f/0x4c
>  [<c1057b40>] __dentry_open+0xc7/0x1aa
>  [<c1057c91>] nameidata_to_filp+0x1c/0x2e
>  [<c1057cd1>] do_filp_open+0x2e/0x35
>  [<c1057dd7>] do_sys_open+0x38/0x68
>  [<c1057e33>] sys_open+0x16/0x18
>  [<c1002845>] sysenter_past_esp+0x56/0x8d

OK, I'm having a look here; its all new to me so bear with me.

blkdev_open() calls
  do_open(bdev, ...,BD_MUTEX_NORMAL) and takes
    mutex_lock_nested(&bdev->bd_mutex, BD_MUTEX_NORMAL)

then something fails, and we're thrown to:

out_first: where
    if (bdev != bdev->bd_contains)
      blkdev_put(bdev->bd_contains) which is
        __blkdev_put(bdev->bd_contains, BD_MUTEX_NORMAL) which does
          mutex_lock_nested(&bdev->bd_contains->bd_mutex, BD_MUTEX_NORMAL) <--- lockdep trigger

When going to out_first, dbev->bd_contains is either bdev or whole, and
since we take the branch it must be whole. So it seems to me the
following patch would be the right one:

[akpm@osdl.org: compile fix]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-27 11:01:29 -07:00
..
9p [PATCH] 9p: fix fid behavior on failed remove 2006-07-31 13:28:44 -07:00
adfs [PATCH] adfs error message fix 2006-08-14 12:54:28 -07:00
affs [PATCH] mark address_space_operations const 2006-06-28 14:59:04 -07:00
afs [PATCH] mark address_space_operations const 2006-06-28 14:59:04 -07:00
autofs [PATCH] VFS: Permit filesystem to override root dentry on mount 2006-06-23 07:42:45 -07:00
autofs4 [PATCH] fs: use list_move() 2006-06-26 09:58:18 -07:00
befs [PATCH] Fix BeFS slab corruption 2006-08-06 08:57:48 -07:00
bfs [PATCH] mark address_space_operations const 2006-06-28 14:59:04 -07:00
cifs Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
coda [PATCH] Remove incorrect unlock_kernel from allocation failure path in coda_open() 2006-07-31 13:28:41 -07:00
configfs configfs: Clear up a few extra spaces where there should be TABs. 2006-06-29 14:43:01 -07:00
cramfs [PATCH] mark address_space_operations const 2006-06-28 14:59:04 -07:00
debugfs Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
devpts [PATCH] VFS: Permit filesystem to override root dentry on mount 2006-06-23 07:42:45 -07:00
efs [PATCH] efs: Remove incorrect unlock_kernel from failure path in efs_symlink_readpage() 2006-07-31 13:28:41 -07:00
exportfs
ext2 [PATCH] lockdep: annotate the quota code 2006-07-03 15:27:08 -07:00
ext3 [PATCH] ext3 -nobh option causes oops 2006-07-31 13:28:44 -07:00
fat [PATCH] mark address_space_operations const 2006-06-28 14:59:04 -07:00
freevxfs [PATCH] freevxfs: Add missing lock_kernel() to vxfs_readdir 2006-07-31 13:28:44 -07:00
fuse [PATCH] fuse: fix error case in fuse_readpages 2006-08-14 12:54:29 -07:00
hfs Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
hfsplus Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
hostfs [PATCH] mark address_space_operations const 2006-06-28 14:59:04 -07:00
hpfs [PATCH] mark address_space_operations const 2006-06-28 14:59:04 -07:00
hppfs [PATCH] VFS: Permit filesystem to perform statfs with a known root dentry 2006-06-23 07:42:45 -07:00
hugetlbfs [PATCH] mmap zero-length hugetlb file with PROT_NONE to protect a hugetlb virtual area 2006-07-10 13:24:21 -07:00
isofs Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
jbd [PATCH] add poison.h and patch primary users 2006-06-27 17:32:38 -07:00
jffs Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
jffs2 Merge git://git.infradead.org/mtd-2.6 2006-07-03 21:29:08 -07:00
jfs JFS: Fix bug in quota code. tmp_bh.b_size must be initialized 2006-07-28 08:46:05 -05:00
lockd LOCKD: Fix a deadlock in nlm_traverse_files() 2006-08-24 15:51:00 -04:00
minix [PATCH] mark address_space_operations const 2006-06-28 14:59:04 -07:00
msdos [PATCH] VFS: Permit filesystem to override root dentry on mount 2006-06-23 07:42:45 -07:00
ncpfs Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial 2006-06-30 15:39:30 -07:00
nfs NFSv4: Add v4 exception handling for the ACL functions. 2006-08-24 15:54:13 -04:00
nfs_common
nfsd [PATCH] knfsd: Fix stale file handle problem with subtree_checking. 2006-07-31 13:28:37 -07:00
nls Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
ntfs [PATCH] lockdep: annotate NTFS locking rules 2006-07-03 15:27:08 -07:00
ocfs2 ocfs2: allocation hints 2006-08-07 11:07:01 -07:00
openpromfs [OPENPROMFS]: Rewrite using in-kernel device tree and seq_file. 2006-06-25 23:19:14 -07:00
partitions [DISKLABEL] SUN: Fix signed int usage for sector count 2006-08-26 17:55:55 -07:00
proc Don't allow chmod() on the /proc/<pid>/ files 2006-07-15 12:26:45 -07:00
qnx4 Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
ramfs [PATCH] NOMMU: Fix execution off of ramfs with mmap() 2006-07-10 13:24:21 -07:00
reiserfs [PATCH] reiserfs_write_full_page() should not get_block past eof 2006-08-06 08:57:49 -07:00
romfs [PATCH] mark address_space_operations const 2006-06-28 14:59:04 -07:00
smbfs Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
sysfs [PATCH] lockdep: annotate the sysfs i_mutex to be a separate class 2006-07-12 12:52:54 -07:00
sysv [PATCH] mark address_space_operations const 2006-06-28 14:59:04 -07:00
udf Fix possible UDF deadlock and memory corruption (CVE-2006-4145) 2006-08-22 12:52:23 -07:00
ufs [PATCH] ufs: handle truncated pages 2006-08-06 08:57:46 -07:00
vfat [PATCH] VFS: Permit filesystem to override root dentry on mount 2006-06-23 07:42:45 -07:00
xfs [XFS] Fix xfs_free_extent related NULL pointer dereference. 2006-08-10 14:40:41 +10:00
aio.c spelling fixes 2006-06-26 18:35:02 +02:00
attr.c
bad_inode.c
binfmt_aout.c
binfmt_elf_fdpic.c [PATCH] FDPIC: Add coredump capability for the ELF-FDPIC binfmt 2006-07-10 13:24:22 -07:00
binfmt_elf.c [PATCH] FDPIC: Move roundup() into linux/kernel.h 2006-07-10 13:24:22 -07:00
binfmt_em86.c
binfmt_flat.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
binfmt_misc.c Merge branch 'master' of /home/trondmy/kernel/linux-2.6/ 2006-06-24 13:07:53 -04:00
binfmt_script.c
binfmt_som.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
bio.c [PATCH] Fix missing ret assignment in __bio_map_user() error path 2006-06-17 10:52:12 -07:00
block_dev.c [PATCH] lockdep: fix blkdev_open() warning 2006-08-27 11:01:29 -07:00
buffer.c [PATCH] invalidate_bdev() speedup 2006-07-31 13:28:38 -07:00
char_dev.c [PATCH] add function documentation for register_chrdev() 2006-07-14 21:53:54 -07:00
compat_ioctl.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
compat.c [PATCH] x86_64: Add compat_printk and sysctl to turn off compat layer warnings 2006-06-26 10:48:16 -07:00
dcache.c [PATCH] lockdep: annotate dcache 2006-07-03 15:27:06 -07:00
dcookies.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
direct-io.c [PATCH] lockdep: annotate direct io 2006-07-03 15:27:06 -07:00
dnotify.c
dquot.c [PATCH] use list_add_tail() instead of list_add() 2006-06-26 09:58:17 -07:00
drop_caches.c
eventpoll.c [PATCH] sched: cleanup, remove task_t, convert to struct task_struct 2006-07-03 15:27:11 -07:00
exec.c VFS: Remove redundant open-coded mode bit checks in open_exec(). 2006-08-24 15:55:16 -04:00
fcntl.c
fifo.c
file_table.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
file.c [PATCH] alloc_fdtable() expansion fix 2006-07-12 12:52:55 -07:00
filesystems.c
fs-writeback.c [PATCH] zoned vm counters: conversion of nr_unstable to per zone counter 2006-06-30 11:25:36 -07:00
inode.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial 2006-06-30 15:39:30 -07:00
inotify_user.c [PATCH] inotify: fix deadlock found by lockdep 2006-07-31 13:28:41 -07:00
inotify.c [PATCH] inotify (4/5): allow watch removal from event handler 2006-06-20 05:25:19 -04:00
ioctl.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
ioprio.c [PATCH] uninline ioprio_best() 2006-08-21 10:02:50 +02:00
Kconfig Merge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6 2006-07-13 16:38:58 -07:00
Kconfig.binfmt
libfs.c [PATCH] core: use list_move() 2006-06-26 09:58:17 -07:00
locks.c [PATCH] fcntl(F_SETSIG) fix 2006-08-14 13:10:59 -07:00
Makefile [PATCH] devfs: Remove devfs from the kernel tree 2006-06-26 12:25:05 -07:00
mbcache.c
mpage.c [PATCH] writeback: fix range handling 2006-06-23 07:42:49 -07:00
namei.c VFS: Fix access("file", X_OK) in the presence of ACLs 2006-08-24 15:54:58 -04:00
namespace.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
nfsctl.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
open.c [PATCH] ftruncate does not always update m/ctime 2006-06-25 10:01:15 -07:00
pipe.c [PATCH] VFS: Permit filesystem to override root dentry on mount 2006-06-23 07:42:45 -07:00
pnode.c [PATCH] core: use list_move() 2006-06-26 09:58:17 -07:00
pnode.h
posix_acl.c
quota_v1.c
quota_v2.c
quota.c
read_write.c [PATCH] fs/read_write.c: EXPORT_UNUSED_SYMBOL 2006-07-10 13:24:18 -07:00
readdir.c
select.c [PATCH] fs: sys_poll with timeout -1 bug fix 2006-06-25 10:01:22 -07:00
seq_file.c
splice.c [PATCH] splice: fix problems with sys_tee() 2006-07-10 11:00:01 +02:00
stat.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
super.c [PATCH] lockdep: annotate sb ->s_umount 2006-07-03 15:27:09 -07:00
sync.c [PATCH] writeback: fix range handling 2006-06-23 07:42:49 -07:00
xattr_acl.c
xattr.c [PATCH] log more info for directory entry change events 2006-06-20 05:25:28 -04:00