On Thu, 23 Jul 2009, Jun'ichi Nomura wrote: > Hi Alasdair, Mikulas, > > I found 2.6.31-rc includes the following commit: > commit 32a926da5a16c01a8213331e5764472ce2f14a8d > Author: Mikulas Patocka <mpatocka@xxxxxxxxxx> > Date: Mon Jun 22 10:12:17 2009 +0100 > > which will introduce a deadlock problem described here: > https://www.redhat.com/archives/dm-devel/2009-May/msg00097.html > (or see below) > > Was the problem fixed/worked around somehow? Hi. I'd submit this. What do others think about it? Mikulas --- Drop the mutex. It doesn't make sense to lock it for a single assignment, this code can't be executed concurrently. The size should be read with i_size_read which is automatically protected against concurrent i_size_write. This locking can lead to a deadlock, if someone holds i_mutex while the device is being suspended, described by Jun'ichi Nomura at https://www.redhat.com/archives/dm-devel/2009-May/msg00097.html Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx> --- drivers/md/dm.c | 2 -- 1 file changed, 2 deletions(-) Index: linux-2.6.31-rc3-devel/drivers/md/dm.c =================================================================== --- linux-2.6.31-rc3-devel.orig/drivers/md/dm.c 2009-07-28 01:20:17.000000000 +0200 +++ linux-2.6.31-rc3-devel/drivers/md/dm.c 2009-07-28 01:20:27.000000000 +0200 @@ -1901,9 +1901,7 @@ static void __set_size(struct mapped_dev { set_capacity(md->disk, size); - mutex_lock(&md->bdev->bd_inode->i_mutex); i_size_write(md->bdev->bd_inode, (loff_t)size << SECTOR_SHIFT); - mutex_unlock(&md->bdev->bd_inode->i_mutex); } static int __bind(struct mapped_device *md, struct dm_table *t, -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
