[SCSI] scsi_dh: fix kconfig related build errors

Do not automatically "select" SCSI_DH for dm-multipath. If SCSI_DH
doesn't exist,just do not allow  hardware handlers to be used.

Handle SCSI_DH being a module also. Make sure it doesn't allow DM_MULTIPATH
to be compiled in when SCSI_DH is a module.

[jejb: added comment for Kconfig syntax]
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index e8f704aa46f2..9f7302d4878d 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -664,6 +664,8 @@ static int parse_hw_handler(struct arg_set *as, struct multipath *m)
         request_module("scsi_dh_%s", m->hw_handler_name);
         if (scsi_dh_handler_exist(m->hw_handler_name) == 0) {
                 ti->error = "unknown hardware handler type";
+                kfree(m->hw_handler_name);
+                m->hw_handler_name = NULL;
                 return -EINVAL;
         }
         consume(as, hw_argc - 1);