From: Mike Snitzer <snitzer@redhat.com>
If the requested scsi_dh module is already loaded then skip
request_module().
Multipath table loads can hang in an unnecessary __request_module.
Reported-by: Ben Marzinski <bmarzins@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
---
drivers/md/dm-mpath.c | 4 ++--
drivers/md/dm-mpath.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
Index: linux-3.4-rc6/drivers/md/dm-mpath.c
===================================================================
--- linux-3.4-rc6.orig/drivers/md/dm-mpath.c
+++ linux-3.4-rc6/drivers/md/dm-mpath.c
@@ -718,8 +718,8 @@ static int parse_hw_handler(struct dm_ar
return 0;
m->hw_handler_name = kstrdup(dm_shift_arg(as), GFP_KERNEL);
- request_module("scsi_dh_%s", m->hw_handler_name);
- if (scsi_dh_handler_exist(m->hw_handler_name) == 0) {
+ if (!try_then_request_module(scsi_dh_handler_exist(m->hw_handler_name),
+ "scsi_dh_%s", m->hw_handler_name)) {
ti->error = "unknown hardware handler type";
ret = -EINVAL;
goto fail;