[S390] dasd: fix endless loop in erp

If not enough memory is available to build a new erp request it ended
up in an endless loop trying to build erp requests. Fixed the loop to
proceed the next request instead.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

2 files changed, 8 insertions, 2 deletions

diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index bbea90baf98f..acf222f91f5a 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -1899,7 +1899,8 @@ restart:
                 /*  Process requests that may be recovered */
                 if (cqr->status == DASD_CQR_NEED_ERP) {
                         erp_fn = base->discipline->erp_action(cqr);
-                        erp_fn(cqr);
+                        if (IS_ERR(erp_fn(cqr)))
+                                continue;
                         goto restart;
                 }
 
diff --git a/drivers/s390/block/dasd_3990_erp.c b/drivers/s390/block/dasd_3990_erp.c
index 6927e751ce3e..6632649dd6aa 100644
--- a/drivers/s390/block/dasd_3990_erp.c
+++ b/drivers/s390/block/dasd_3990_erp.c
@@ -2309,7 +2309,7 @@ static struct dasd_ccw_req *dasd_3990_erp_add_erp(struct dasd_ccw_req *cqr)
                                      cqr->retries);
                         dasd_block_set_timer(device->block, (HZ << 3));
                 }
-                return cqr;
+                return erp;
         }
 
         ccw = cqr->cpaddr;
@@ -2372,6 +2372,9 @@ dasd_3990_erp_additional_erp(struct dasd_ccw_req * cqr)
         /* add erp and initialize with default TIC */
         erp = dasd_3990_erp_add_erp(cqr);
 
+        if (IS_ERR(erp))
+                return erp;
+
         /* inspect sense, determine specific ERP if possible */
         if (erp != cqr) {
 
@@ -2711,6 +2714,8 @@ dasd_3990_erp_action(struct dasd_ccw_req * cqr)
         if (erp == NULL) {
                 /* no matching erp found - set up erp */
                 erp = dasd_3990_erp_additional_erp(cqr);
+                if (IS_ERR(erp))
+                        return erp;
         } else {
                 /* matching erp found - set all leading erp's to DONE */
                 erp = dasd_3990_erp_handle_match_erp(cqr, erp);