diff options
| author | NeilBrown <neilb@suse.de> | 2007-01-26 00:57:11 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-01-26 13:51:00 -0800 |
| commit | 2a2275d630b982e5f90206f9bc497f6695a3ec5d (patch) | |
| tree | 88cddee709b2107b74e5424810d4ffb6e3772382 /include/linux | |
| parent | a0ad13ef643a5829d63c456ab6143bbda60b44a9 (diff) | |
[PATCH] md: fix potential memalloc deadlock in md
If a GFP_KERNEL allocation is attempted in md while the mddev_lock is held,
it is possible for a deadlock to eventuate.
This happens if the array was marked 'clean', and the memalloc triggers a
write-out to the md device.
For the writeout to succeed, the array must be marked 'dirty', and that
requires getting the mddev_lock.
So, before attempting a GFP_KERNEL allocation while holding the lock, make
sure the array is marked 'dirty' (unless it is currently read-only).
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/raid/md.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/linux/raid/md.h b/include/linux/raid/md.h index 866a1e2b0ce0..fbaeda79b2e9 100644 --- a/include/linux/raid/md.h +++ b/include/linux/raid/md.h @@ -94,7 +94,7 @@ extern int sync_page_io(struct block_device *bdev, sector_t sector, int size, struct page *page, int rw); extern void md_do_sync(mddev_t *mddev); extern void md_new_event(mddev_t *mddev); - +extern void md_allow_write(mddev_t *mddev); #endif /* CONFIG_MD */ #endif |