On Fri, Feb 24, 2017 at 11:15:18AM +0800, Guoqing Jiang wrote: > After used sync way to handle METADATA_UPDATED msg, a deadlock > could appear if stop a resyncing array. shouldn't this put into the patch of 'handle METADATA_UPDATED' msg? > betalinux244:~ # ps aux|grep md|grep D > root 17164 0.0 0.0 0 0 ? D Jan09 0:00 [md0_cluster_rec] > root 18151 0.0 0.1 19852 2008 ? Ds Jan09 0:00 /sbin/mdadm -Ssq > betalinux244:~ # cat /proc/17164/stack > [<ffffffffa06a7395>] recv_daemon+0x1f5/0x590 [md_cluster] > [<ffffffffa067be20>] md_thread+0x130/0x150 [md_mod] > [<ffffffff810995ed>] kthread+0xbd/0xe0 > [<ffffffff815e96bf>] ret_from_fork+0x3f/0x70 > [<ffffffff81099530>] kthread+0x0/0xe0 > [<ffffffffffffffff>] 0xffffffffffffffff > betalinux244:~ # cat /proc/18151/stack > [<ffffffff81099879>] kthread_stop+0x59/0x130 > [<ffffffffa067c566>] md_unregister_thread+0x46/0x80 [md_mod] > [<ffffffffa06a6e71>] leave+0x81/0x120 [md_cluster] > [<ffffffffa0684e94>] md_cluster_stop+0x14/0x30 [md_mod] > [<ffffffffa06858b6>] bitmap_free+0x126/0x130 [md_mod] > [<ffffffffa0682d06>] do_md_stop+0x356/0x5f0 [md_mod] > [<ffffffffa0683cbe>] md_ioctl+0x6fe/0x1680 [md_mod] > [<ffffffff812ed158>] blkdev_ioctl+0x258/0x920 > [<ffffffff8122f81d>] block_ioctl+0x3d/0x40 > [<ffffffff8120ac0d>] do_vfs_ioctl+0x2cd/0x4a0 > [<ffffffff8120ae54>] SyS_ioctl+0x74/0x80 > [<ffffffff815e936e>] entry_SYSCALL_64_fastpath+0x12/0x6d > [<ffffffffffffffff>] 0xffffffffffffffff > > Since md_unregister_thread(&cinfo->recv_thread) is blocked by > recv_daemon -> process_recvd_msg -> process_metadata_update. > To resolve the issue, MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD is > also need to be set before unregister thread. > > Reviewed-by: NeilBrown <neilb@xxxxxxxx> > Signed-off-by: Guoqing Jiang <gqjiang@xxxxxxxx> > --- > drivers/md/md-cluster.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c > index 0aad477d1b20..5e2c54be6f30 100644 > --- a/drivers/md/md-cluster.c > +++ b/drivers/md/md-cluster.c > @@ -932,6 +932,7 @@ static int join(struct mddev *mddev, int nodes) > > return 0; > err: > + set_bit(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state); > md_unregister_thread(&cinfo->recovery_thread); > md_unregister_thread(&cinfo->recv_thread); > lockres_free(cinfo->message_lockres); > @@ -987,6 +988,7 @@ static int leave(struct mddev *mddev) > if (cinfo->slot_number > 0 && mddev->recovery_cp != MaxSector) > resync_bitmap(mddev); > > + set_bit(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state); > md_unregister_thread(&cinfo->recovery_thread); > md_unregister_thread(&cinfo->recv_thread); > lockres_free(cinfo->message_lockres); > -- > 2.6.2 > > -- > 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 -- 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
