commit 91b0a8f33419573c1d741e49559bfb666fd8b1f0
author Cornelia Huck <cornelia.huck@de.ibm.com> Thu Feb 07 02:20:51 2013 +0000
committer Anthony Liguori <aliguori@us.ibm.com> Wed Feb 13 11:56:02 2013 -0600
tree 7b567f0af4b64b3f2274719b008f21f5f4b7ec7d
parent bd9a8d852c857fd19c4626acaac1d4979f816f3a

s390: Fix handling of iscs.

There are two ways to express an interruption subclass:
- As a bitmask, as used in cr6.
- As a number, as used in the I/O interruption word.

Unfortunately, we have treated to I/O interruption word as if it
contained the bitmask as well, which went unnoticed so far as
- (queued-for-next) kvm made the same mistake, and
- Linux guest kernels don't check the isc value in the I/O interruption
  word for subchannel interrupts.

Make sure that we treat the I/O interruption word correctly.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>

hw/s390x/css.c

diff --git a/hw/s390x/css.c b/hw/s390x/css.c
index 3244201..85f6f22 100644
--- a/hw/s390x/css.c
+++ b/hw/s390x/css.c
@@ -87,7 +87,7 @@
                       css_build_subchannel_id(sch),
                       sch->schid,
                       sch->curr_status.pmcw.intparm,
-                      (0x80 >> isc) << 24);
+                      isc << 27);
 }
 
 void css_conditional_io_interrupt(SubchDev *sch)
@@ -111,7 +111,7 @@
                           css_build_subchannel_id(sch),
                           sch->schid,
                           sch->curr_status.pmcw.intparm,
-                          (0x80 >> isc) << 24);
+                          isc << 27);
     }
 }