kernel_optimize_test/fs
Oleg Nesterov abd96ecb29 exec: kill unsafe BUG_ON(sig->count) checks
de_thread:

	if (atomic_read(&oldsighand->count) <= 1)
		BUG_ON(atomic_read(&sig->count) != 1);

This is not safe without the rmb() in between.  The results of two
correctly ordered __exit_signal()->atomic_dec_and_test()'s could be seen
out of order on our CPU.

The same is true for the "thread_group_empty()" case, __unhash_process()'s
changes could be seen before atomic_dec_and_test(&sig->count).

On some platforms (including i386) atomic_read() doesn't provide even the
compiler barrier, in that case these checks are simply racy.

Remove these BUG_ON()'s. Alternatively, we can do something like

	BUG_ON( ({ smp_rmb(); atomic_read(&sig->count) != 1; }) );

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-08-22 19:52:47 -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 Replace pid_t in autofs with struct pid reference 2007-05-11 08:29:36 -07:00
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 mm: make read_cache_page synchronous 2007-05-07 12:12:51 -07:00
debugfs debugfs: remove rmdir() non-empty complaint 2007-07-18 15:49:48 -07:00
devpts devpts: add fsnotify create event 2007-05-08 11:14:59 -07:00
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 sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
hpfs mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
hppfs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
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 [PATCH] mark struct inode_operations const 2 2007-02-12 09:48:46 -08:00
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 NLS: Remove obsolete Makefile entries 2007-07-16 09:05:52 -07:00
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 [PATCH] mark struct inode_operations const 3 2007-02-12 09:48:46 -08:00
xfs xfs ioctl __user annotations 2007-07-26 11:11:57 -07:00
aio.c signal/timer/event: KAIO eventfd support example 2007-05-11 08:29:37 -07:00
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 sendfile: remove bad_sendfile() from bad_file_ops 2007-07-10 08:04:15 +02:00
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 header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
binfmt_flat.c nommu: report correct errno in message 2007-06-08 17:23:32 -07:00
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 invalidate_mapping_pages(): add cond_resched 2007-07-16 09:05:36 -07:00
eventfd.c eventfd use waitqueue lock ... 2007-05-18 13:09:34 -07:00
eventpoll.c mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
exec.c exec: kill unsafe BUG_ON(sig->count) checks 2007-08-22 19:52:47 -07:00
fcntl.c mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
fifo.c Detach sched.h from mm.h 2007-05-21 09:18:19 -07:00
file_table.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
file.c
filesystems.c add filesystem subtype support 2007-05-08 11:15:01 -07:00
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 Introduce a handy list_first_entry macro 2007-05-08 11:15:11 -07:00
internal.h cleanup compat ioctl handling 2007-05-08 11:15:09 -07:00
ioctl.c drop obsolete sys_ioctl export 2007-07-16 09:05:48 -07:00
ioprio.c [PATCH] pid: replace do/while_each_task_pid with do/while_each_pid_task 2007-02-12 09:48:32 -08:00
Kconfig NFSD/SUNRPC: Fix the automatic selection of RPCSEC_GSS 2007-07-19 15:09:02 -04:00
Kconfig.binfmt fs: Kill sh dependency for binfmt_flat. 2007-05-21 14:34:00 +09:00
libfs.c fs/libfs.c: >80 columns line break fix 2007-05-09 06:44:57 +02:00
locks.c rename setlease to generic_setlease 2007-07-31 15:39:43 -07:00
Makefile signal/timer/event: eventfd core 2007-05-11 08:29:36 -07:00
mbcache.c mm: Remove slab destructors from kmem_cache_create(). 2007-07-20 10:11:58 +09:00
mpage.c consolidate generic_writepages and mpage_writepages 2007-05-11 08:29:35 -07:00
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 Introduce a handy list_first_entry macro 2007-05-08 11:15:11 -07:00
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 Remove remnants of sendfile() 2007-07-10 08:04:15 +02:00
read_write.h
readdir.c ROUND_UP macro cleanup in fs/(select|compat|readdir).c 2007-05-08 11:15:09 -07:00
select.c Style fix in fs/select.c 2007-05-09 07:10:02 +02:00
seq_file.c seq_file: more atomicity in traverse() 2007-07-16 09:05:45 -07:00
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 [PATCH] fs/stack.c: Copy i_nlink after all other attributes are copied 2007-02-19 14:21:50 -08:00
stat.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
super.c hugetlbfs: handle empty options string 2007-07-16 09:05:46 -07:00
sync.c Introduce fixed sys_sync_file_range2() syscall, implement on PowerPC and ARM 2007-06-28 11:38:30 -07:00
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 [PATCH] remove many unneeded #includes of sched.h 2007-02-14 08:09:54 -08:00
xattr.c Introduce is_owner_or_cap() to wrap CAP_FOWNER use with fsuid check 2007-07-17 12:00:03 -07:00