Linus Torvalds 1be62dc190 Be more careful about marking buffers dirty ... Mikulas Patocka noted that the optimization where we check if a buffer was already dirty (and we avoid re-dirtying it) was not really SMP-safe. Since the read of the old status was not synchronized with anything, an aggressive CPU re-ordering of memory accesses might have moved that read up to before the data was even written to the buffer, and another CPU that cleaned it again, causing the newly dirty state to never actually hit the disk. Admittedly this would probably never trigger in practice, but it's still wrong. Mikulas sent a patch that fixed the problem, but I dislike the subtlety of the whole optimization, so this is an alternate fix that is more explicit about the particular SMP ordering for the optimization, and separates out the speculative reads of the buffer state into its own conditional (and makes the memory barrier only happen if we are likely to actually hit the optimized case in the first place). I considered removing the optimization entirely, but Andrew argued for it's continued existence. I'm a push-over. Cc: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2008-04-04 14:38:17 -07:00
..
9p	Convert ERR_PTR(PTR_ERR(p)) instances to ERR_CAST(p)	2008-02-07 08:42:26 -08:00
adfs	mount options: fix adfs	2008-02-08 09:22:39 -08:00
affs	mount options: fix affs	2008-02-08 09:22:39 -08:00
afs	afs: remove smp_prcessor_id() from debug macro	2008-04-03 15:40:53 -07:00
autofs	mount options: fix autofs	2008-02-08 09:22:40 -08:00
autofs4	Introduce path_put()	2008-02-14 21:13:33 -08:00
befs	mount options: fix befs	2008-02-08 09:22:40 -08:00
bfs	iget: stop BFS from using iget() and read_inode()	2008-02-07 08:42:27 -08:00
cifs	cifs: fix misannotations	2008-03-30 14:20:23 -07:00
coda	Introduce path_put()	2008-02-14 21:13:33 -08:00
configfs	Introduce path_put()	2008-02-14 21:13:33 -08:00
cramfs	fs/cramfs/inode.c: replace hardcoded value with preprocessor constant	2007-10-18 14:37:29 -07:00
debugfs	debugfs: fix sparse warnings	2008-03-04 14:47:06 -08:00
devpts	mount options: fix devpts	2008-02-08 09:22:40 -08:00
dlm	dlm: fix rcom_names message to self	2008-02-21 15:19:54 -06:00
ecryptfs	eCryptfs: Swap dput() and mntput()	2008-03-19 18:53:36 -07:00
efs	efs: update error msg to not refer to deleted read_inode()	2008-04-02 15:28:19 -07:00
exportfs	exportfs: update documentation	2007-10-22 08:13:21 -07:00
ext2	mount options: fix ext2	2008-02-08 09:22:40 -08:00
ext3	ext3: fix wrong gfp type under transaction	2008-03-19 18:53:36 -07:00
ext4	ext4: add missing ext4_journal_stop()	2008-02-25 15:37:42 -05:00
fat	mount options: fix fat	2008-02-08 09:22:40 -08:00
freevxfs	iget: stop FreeVXFS from using iget() and read_inode()	2008-02-07 08:42:28 -08:00
fuse	fuse: fix permission checking	2008-02-23 17:12:13 -08:00
gfs2	Introduce path_put()	2008-02-14 21:13:33 -08:00
hfs	hfs_bnode_find() can fail, resulting in hfs_bnode_split() breakage	2008-03-17 09:46:55 -07:00
hfsplus	fs/hfsplus/unicode.c: fix uninitialized var warning	2008-02-08 09:22:36 -08:00
hostfs	uml: fix hostfs tv_usec calculations	2008-02-05 09:44:30 -08:00
hpfs	mount options: fix hpfs	2008-02-08 09:22:40 -08:00
hppfs	[PATCH] sanitize hppfs	2008-03-19 06:42:18 -04:00
hugetlbfs	[PATCH] double iput() on failure exit in hugetlb	2008-03-19 06:55:01 -04:00
isofs	zisofs: fix readpage() outside i_size	2008-03-19 18:53:36 -07:00
jbd	jbd/jbd2 NULL noise	2008-03-30 14:18:41 -07:00
jbd2	jbd/jbd2 NULL noise	2008-03-30 14:18:41 -07:00
jffs2	Merge git://git.infradead.org/mtd-2.6	2008-02-07 10:20:31 -08:00
jfs	BKL-removal: Implement a compat_ioctl handler for JFS	2008-02-07 13:45:29 -06:00
lockd	Wrap buffers used for rpc debug printks into RPC_IFDEBUG	2008-02-21 18:42:29 -05:00
minix	iget: stop the MINIX filesystem from using iget() and read_inode()	2008-02-07 08:42:28 -08:00
msdos
ncpfs	mount options: fix ncpfs	2008-02-08 09:22:40 -08:00
nfs	[PATCH] do shrink_submounts() for all fs types	2008-03-27 20:47:58 -04:00
nfs_common
nfsd	nfsd: fix oops on access from high-numbered ports	2008-03-14 16:49:15 -07:00
nls	sparse pointer use of zero as null	2007-10-18 14:37:31 -07:00
ntfs	is_vmalloc_addr(): Check if an address is within the vmalloc boundaries	2008-02-05 09:44:14 -08:00
ocfs2	ocfs2: Fix NULL pointer dereferences in o2net	2008-03-10 15:14:19 -07:00
openpromfs	iget: stop OPENPROMFS from using iget() and read_inode()	2008-02-07 08:42:29 -08:00
partitions	Enhanced partition statistics: remove old partition statistics	2008-02-08 12:42:01 +01:00
proc	Change pagemap output format to allow for future reporting of huge pages	2008-03-22 17:03:10 -07:00
qnx4	iget: stop QNX4 from using iget() and read_inode()	2008-02-07 08:42:28 -08:00
ramfs	Remove valueless definition of hard-selected RAMFS option	2007-10-17 08:42:56 -07:00
reiserfs	NULL noise: fs/*, mm/*, kernel/*	2008-03-30 14:18:41 -07:00
romfs	ROMFS: Fix up an error in iget removal	2008-03-19 18:53:36 -07:00
smbfs	NULL noise: fs/*, mm/*, kernel/*	2008-03-30 14:18:41 -07:00
sysfs	driver core: debug for bad dev_attr_show() return value.	2008-03-24 22:33:49 -07:00
sysv	iget: stop the SYSV filesystem from using iget() and read_inode()	2008-02-07 08:42:29 -08:00
udf	udf: fix udf_add_free_space	2008-02-13 16:21:20 -08:00
ufs	fs/ufs/balloc.c: fix sparc64 printk warning	2008-03-19 18:53:37 -07:00
vfat	Convert ERR_PTR(PTR_ERR(p)) instances to ERR_CAST(p)	2008-02-07 08:42:26 -08:00
xfs	[XFS] fix inode leak in xfs_iget_core()	2008-03-06 16:38:50 +11:00
aio.c	aio: bad AIO race in aio_complete() leads to process hang	2008-03-19 18:53:35 -07:00
anon_inodes.c	[PATCH] fix up new filp allocators	2008-03-19 06:54:05 -04:00
attr.c	VFS: make notify_change pass ATTR_KILL_S*ID to setattr operations	2007-10-18 14:37:22 -07:00
bad_inode.c	iget: introduce a function to register iget failure	2008-02-07 08:42:26 -08:00
binfmt_aout.c	aout: suppress A.OUT library support if !CONFIG_ARCH_SUPPORTS_AOUT	2008-02-08 09:22:30 -08:00
binfmt_elf.c	core dump: user_regset writeback	2008-03-04 16:35:10 -08:00
binfmt_elf_fdpic.c	pid namespaces: changes to show virtual ids to user	2007-10-19 11:53:40 -07:00
binfmt_em86.c	Convert files to UTF-8 and some cleanups	2007-10-19 23:21:04 +02:00
binfmt_flat.c	FLAT binaries: drop BINFMT_FLAT bad header magic warning	2008-02-14 20:58:05 -08:00
binfmt_misc.c	Convert files to UTF-8 and some cleanups	2007-10-19 23:21:04 +02:00
binfmt_script.c	Convert files to UTF-8 and some cleanups	2007-10-19 23:21:04 +02:00
binfmt_som.c	aout: remove unnecessary inclusions of {asm, linux}/a.out.h	2008-02-08 09:22:30 -08:00
bio.c	Revert "unexport bio_{,un}map_user"	2008-03-17 21:14:40 +01:00
block_dev.c	fs/block_dev.c: remove #if 0'ed code	2008-02-19 10:04:00 +01:00
buffer.c	Be more careful about marking buffers dirty	2008-04-04 14:38:17 -07:00
char_dev.c	fs/char_dev.c: chrdev_open marked static and removed from fs.h	2008-02-08 09:22:42 -08:00
compat.c	Merge branch 'linus_origin' into hotfixes	2008-02-15 13:36:30 -05:00
compat_binfmt_elf.c	x86: compat_binfmt_elf	2008-01-30 13:31:46 +01:00
compat_ioctl.c	d_path: Make d_path() use a struct path	2008-02-14 21:17:09 -08:00
dcache.c	dentries: Extract common code to remove dentry from lru	2008-02-14 21:17:09 -08:00
dcookies.c	d_path: Make d_path() use a struct path	2008-02-14 21:17:09 -08:00
direct-io.c	Pagecache zeroing: zero_user_segment, zero_user_segments and zero_user	2008-02-05 09:44:13 -08:00
dnotify.c	mm: Remove slab destructors from kmem_cache_create().	2007-07-20 10:11:58 +09:00
dquot.c	quota: add possibly missing iput() when quotaon and quotaoff races	2008-03-19 18:53:35 -07:00
drop_caches.c	invalidate_mapping_pages(): add cond_resched	2007-07-16 09:05:36 -07:00
eventfd.c	fs/eventfd.c should #include <linux/syscalls.h>	2008-02-06 10:41:03 -08:00
eventpoll.c	lockdep: annotate epoll	2008-02-05 09:44:07 -08:00
exec.c	Allow ARG_MAX execve string space even with a small stack limit	2008-03-03 10:12:14 -08:00
fcntl.c	fs: remove fastcall, it is always empty	2008-02-08 09:22:31 -08:00
fifo.c
file.c	get rid of NR_OPEN and introduce a sysctl_nr_open	2008-02-06 10:41:06 -08:00
file_table.c	[PATCH] fix up new filp allocators	2008-03-19 06:54:05 -04:00
filesystems.c
fs-writeback.c	fs: fix kernel-doc notation warnings	2008-03-19 18:53:36 -07:00
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	iget: remove iget() and the read_inode() super op as being obsolete	2008-02-07 08:42:29 -08:00
inotify.c	inotify: remove debug code	2008-02-06 10:41:07 -08:00
inotify_user.c	Introduce path_put()	2008-02-14 21:13:33 -08:00
internal.h
ioctl.c	fix up kerneldoc in fs/ioctl.c a little bit	2008-02-09 11:08:33 -08:00
ioprio.c	cfq-iosched: relax IOPRIO_CLASS_IDLE restrictions	2008-01-28 11:38:15 +01:00
Kconfig	deprecate smbfs in favour of cifs	2008-02-05 14:37:15 -08:00
Kconfig.binfmt	aout: suppress A.OUT library support if !CONFIG_ARCH_SUPPORTS_AOUT	2008-02-08 09:22:30 -08:00
libfs.c	Pagecache zeroing: zero_user_segment, zero_user_segments and zero_user	2008-02-05 09:44:13 -08:00
locks.c	fs: fix kernel-doc notation warnings	2008-03-19 18:53:36 -07:00
Makefile	x86: compat_binfmt_elf Kconfig	2008-01-30 13:31:46 +01:00
mbcache.c	fs: Fix to correct the mbcache entries counter	2007-10-25 15:18:29 -07:00
mpage.c	docbook: fix filesystems.tmpl source files	2008-03-03 10:47:13 -08:00
namei.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6	2008-03-25 08:57:47 -07:00
namespace.c	[PATCH] mnt_expire is protected by namespace_sem, no need for vfsmount_lock	2008-03-27 20:48:04 -04:00
nfsctl.c	Introduce path_put()	2008-02-14 21:13:33 -08:00
no-block.c
open.c	[PATCH] check for null vfsmount in dentry_open()	2008-03-19 06:50:44 -04:00
pipe.c	[PATCH] fix up new filp allocators	2008-03-19 06:54:05 -04:00
pnode.c	[PATCH] count ghost references to vfsmounts	2008-03-27 20:47:46 -04:00
pnode.h	[PATCH] new helpers - collect_mounts() and release_collected_mounts()	2007-10-21 02:37:25 -04:00
posix_acl.c
quota.c	Convert ERR_PTR(PTR_ERR(p)) instances to ERR_CAST(p)	2008-02-07 08:42:26 -08:00
quota_v1.c
quota_v2.c
read_write.c	remove the unused exports of sys_open/sys_read	2008-02-08 09:22:36 -08:00
read_write.h
readdir.c	Use mutex_lock_killable in vfs_readdir	2007-12-06 17:39:54 -05:00
select.c	make sys_poll() wait at least timeout ms	2008-02-06 10:41:09 -08:00
seq_file.c	d_path: Make d_path() use a struct path	2008-02-14 21:17:09 -08:00
signalfd.c	fs/signalfd.c should #include <linux/syscalls.h>	2008-02-06 10:41:03 -08:00
splice.c	splice: use mapping_gfp_mask	2008-04-03 15:39:49 -07:00
stack.c
stat.c	Introduce path_put()	2008-02-14 21:13:33 -08:00
super.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6	2008-03-25 08:57:47 -07:00
sync.c
timerfd.c	timerfd: new timerfd API	2008-02-05 09:44:07 -08:00
utimes.c	Introduce path_put()	2008-02-14 21:13:33 -08:00
xattr.c	Introduce path_put()	2008-02-14 21:13:33 -08:00
xattr_acl.c