dm mpath: rdac fix init race
Alasdair G Kergon
maintainerPATCH 1/25 dm mpath: rdac fix init race
From: Bryn M. Reeves <[email protected]>
Re-order the initialisation of dm-rdac to avoid registering the hw handler before the workqueue has been initialised. Closes a race that would potentially give an oops.
Signed-off-by Bryn M. Reeves <[email protected]>
Signed-off-by Alasdair G Kergon <[email protected]>
--- drivers/md/dm-mpath-rdac.c | 15 ++++++++------- 1 files changed, 8 insertions(+), 7 deletions(-)
drivers/md/dm-mpath-rdac.c +8 -7
@@ -664,20 +664,21 @@ static struct hw_handler_type rdac_handlstatic int __init rdac_init (void ) { -int r =dm_register_hw_handler (&rdac_handler); - -if (r <0 ) { -DMERR ("%s: register failed %d" ,RDAC_DM_HWH_NAME , r); -return r; - } +int r; rdac_wkqd =create_singlethread_workqueue ("rdac_wkqd" );if (!rdac_wkqd) {DMERR ("Failed to create workqueue rdac_wkqd." ); -dm_unregister_hw_handler (&rdac_handler);return -ENOMEM ; } + r =dm_register_hw_handler (&rdac_handler); +if (r <0 ) { +DMERR ("%s: register failed %d" ,RDAC_DM_HWH_NAME , r); +destroy_workqueue (rdac_wkqd); +return r; + } +DMINFO ("%s: version %s loaded" ,RDAC_DM_HWH_NAME ,RDAC_DM_HWH_VER );return 0 ; }