[S390] cio: Make isc handling more robust.

Introduce an ->isc field in the subchannel to store the desired
interruption subclass, since sch->schib.pmcw.isc may be overwritten
by the hardware on stsch() after machine checks.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 3 insertions, 7 deletions

diff --git a/drivers/s390/cio/device_fsm.c b/drivers/s390/cio/device_fsm.c
index 4b92c84fb438..99403b0a97a7 100644
--- a/drivers/s390/cio/device_fsm.c
+++ b/drivers/s390/cio/device_fsm.c
@@ -555,8 +555,7 @@ ccw_device_recognition(struct ccw_device *cdev)
             (cdev->private->state != DEV_STATE_BOXED))
                 return -EINVAL;
         sch = to_subchannel(cdev->dev.parent);
-        ret = cio_enable_subchannel(sch, sch->schib.pmcw.isc,
-                                    (u32)(addr_t)sch);
+        ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
         if (ret != 0)
                 /* Couldn't enable the subchannel for i/o. Sick device. */
                 return ret;
@@ -667,8 +666,7 @@ ccw_device_online(struct ccw_device *cdev)
         sch = to_subchannel(cdev->dev.parent);
         if (css_init_done && !get_device(&cdev->dev))
                 return -ENODEV;
-        ret = cio_enable_subchannel(sch, sch->schib.pmcw.isc,
-                                    (u32)(addr_t)sch);
+        ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
         if (ret != 0) {
                 /* Couldn't enable the subchannel for i/o. Sick device. */
                 if (ret == -ENODEV)
@@ -1048,8 +1046,7 @@ ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
         struct subchannel *sch;
 
         sch = to_subchannel(cdev->dev.parent);
-        if (cio_enable_subchannel(sch, sch->schib.pmcw.isc,
-                                  (u32)(addr_t)sch) != 0)
+        if (cio_enable_subchannel(sch, (u32)(addr_t)sch) != 0)
                 /* Couldn't enable the subchannel for i/o. Sick device. */
                 return;
 
@@ -1082,7 +1079,6 @@ device_trigger_reprobe(struct subchannel *sch)
          */
         sch->lpm = sch->schib.pmcw.pam & sch->opm;
         /* Re-set some bits in the pmcw that were lost. */
-        sch->schib.pmcw.isc = 3;
         sch->schib.pmcw.csense = 1;
         sch->schib.pmcw.ena = 0;
         if ((sch->lpm & (sch->lpm - 1)) != 0)