diff options
| author | NeilBrown <neilb@suse.de> | 2007-01-25 15:35:34 +1100 |
|---|---|---|
| committer | Chris Wright <chrisw@sous-sol.org> | 2007-02-05 08:31:43 -0800 |
| commit | ec803d270172c7329be48faf49ff3095a54c4a56 (patch) | |
| tree | 2711ba33b1fc0cc13ab78d934100f2319d5be137 /include | |
| parent | 50c524829e518ca5a7e3e5423726e6bb24afaac4 (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 alloction 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: Chris Wright <chrisw@sous-sol.org>
Diffstat (limited to 'include')
| -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 |