[PATCH] md: delay starting md threads until array is completely setup

When an array is started we start one or two threads (two if there is a
reshape or recovery that needs to be completed).

We currently start these *before* the array is completely set up and in
particular before queue->queuedata is set.  If the thread actually starts
very quickly on another CPU, we can end up dereferencing queue->queuedata
and oops.

This patch also makes sure we don't try to start a recovery if a reshape is
being restarted.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
NeilBrown 2006-07-10 04:44:15 -07:00 committed by Linus Torvalds
parent 31b65a0d38
commit 0b8c9de05c
2 changed files with 4 additions and 7 deletions

View file

@ -3095,7 +3095,6 @@ static int do_md_run(mddev_t * mddev)
}
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
md_wakeup_thread(mddev->thread);
if (mddev->sb_dirty)
md_update_sb(mddev);
@ -3116,7 +3115,7 @@ static int do_md_run(mddev_t * mddev)
* start recovery here. If we leave it to md_check_recovery,
* it will remove the drives and not do the right thing
*/
if (mddev->degraded) {
if (mddev->degraded && !mddev->sync_thread) {
struct list_head *rtmp;
int spares = 0;
ITERATE_RDEV(mddev,rdev,rtmp)
@ -3137,10 +3136,11 @@ static int do_md_run(mddev_t * mddev)
mdname(mddev));
/* leave the spares where they are, it shouldn't hurt */
mddev->recovery = 0;
} else
md_wakeup_thread(mddev->sync_thread);
}
}
}
md_wakeup_thread(mddev->thread);
md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
mddev->changed = 1;
md_new_event(mddev);

View file

@ -3246,9 +3246,6 @@ static int run(mddev_t *mddev)
set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
mddev->sync_thread = md_register_thread(md_do_sync, mddev,
"%s_reshape");
/* FIXME if md_register_thread fails?? */
md_wakeup_thread(mddev->sync_thread);
}
/* read-ahead size must cover two whole stripes, which is