On Fri, 06 Aug 2010 15:11:58 +0530 ravichandra <vmynidi@xxxxxxxxxxxxxxxxxx> wrote: > Hi everyone, > I used 2 (1 TB disks) disks each with 3 > partitions(sda[1-3] and sdb[1-3]).Using sda[1-2] and sdb[1-2] i have > created a RAID10 array say md2. Then i was reading and writing to the > array and simultaneously removing a disk and adding it to the same > array. In the process i got a hang causing recovery process to halt. The > array was not operational after.These were done on kernel 2.6.31. > > I am working on the RAID10 for the first time. Can someone > help in this so that i can proceed further?? > > Thanks in advance. Known problem. I'll be submitting the fix upstream shortly. I include it below. Thanks for the report NeilBrown > > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 42e64e4..d1d6891 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -825,11 +825,29 @@ static int make_request(mddev_t *mddev, struct bio * bio) */ bp = bio_split(bio, chunk_sects - (bio->bi_sector & (chunk_sects - 1)) ); + + /* Each of these 'make_request' calls will call 'wait_barrier'. + * If the first succeeds but the second blocks due to the resync + * thread raising the barrier, we will deadlock because the + * IO to the underlying device will be queued in generic_make_request + * and will never complete, so will never reduce nr_pending. + * So increment nr_waiting here so no new raise_barriers will + * succeed, and so the second wait_barrier cannot block. + */ + spin_lock_irq(&conf->resync_lock); + conf->nr_waiting++; + spin_unlock_irq(&conf->resync_lock); + if (make_request(mddev, &bp->bio1)) generic_make_request(&bp->bio1); if (make_request(mddev, &bp->bio2)) generic_make_request(&bp->bio2); + spin_lock_irq(&conf->resync_lock); + conf->nr_waiting--; + wake_up(&conf->wait_barrier); + spin_unlock_irq(&conf->resync_lock); + bio_pair_release(bp); return 0; bad_map: -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
