dm mpath: fix ioctl deadlock when no paths

When multipath needs to retry an ioctl the reference to the
current live table needs to be dropped. Otherwise a deadlock
occurs when all paths are down:
- dm_blk_ioctl takes a reference to the current table
  and spins in multipath_ioctl().
- A new table is being loaded, but upon resume the process
  hangs in dm_table_destroy() waiting for references to
  drop to zero.

With this patch the reference to the old table is dropped
prior to retry, thereby avoiding the deadlock.

Signed-off-by: Hannes Reinecke <[email protected]>
Cc: Mike Snitzer <[email protected]>
Cc: [email protected]
Signed-off-by: Alasdair G Kergon <[email protected]>

0 files changed, 0 insertions, 0 deletions