[patch 096/108] dm: sysfs skip output when device is being destroyed

[Greg KH]

2.6.30-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Milan Broz <mbroz@xxxxxxxxxx>

commit 4d89b7b4e4726893453d0fb4ddbb5b3e16353994 upstream.

Do not process sysfs attributes when device is being destroyed.

Otherwise code can cause
  BUG_ON(test_bit(DMF_FREEING, &md->flags));
in dm_put() call.

Signed-off-by: Milan Broz <mbroz@xxxxxxxxxx>
Signed-off-by: Alasdair G Kergon <agk@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
 drivers/md/dm.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1780,6 +1780,10 @@ struct mapped_device *dm_get_from_kobjec
 	if (&md->kobj != kobj)
 		return NULL;
 
+	if (test_bit(DMF_FREEING, &md->flags) ||
+	    test_bit(DMF_DELETING, &md->flags))
+		return NULL;
+
 	dm_get(md);
 	return md;
 }


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/