[Qemu-devel] [PULL SUBSYSTEM s390x 09/10] s390-ccw: force diag 308 subcode to unsigned long

Thomas Huth posted 10 patches 7 years, 7 months ago
Only 9 patches received!
[Qemu-devel] [PULL SUBSYSTEM s390x 09/10] s390-ccw: force diag 308 subcode to unsigned long
Posted by Thomas Huth 7 years, 7 months ago
From: Cornelia Huck <cohuck@redhat.com>

We currently pass an integer as the subcode parameter. However,
the upper bits of the register containing the subcode need to
be 0, which is not guaranteed unless we explicitly specify the
subcode to be an unsigned long value.

Fixes: d046c51dad3 ("pc-bios/s390-ccw: Get device address via diag 308/6")
Cc: qemu-stable@nongnu.org
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 pc-bios/s390-ccw/iplb.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/pc-bios/s390-ccw/iplb.h b/pc-bios/s390-ccw/iplb.h
index 5357a36..ded20c8 100644
--- a/pc-bios/s390-ccw/iplb.h
+++ b/pc-bios/s390-ccw/iplb.h
@@ -101,10 +101,11 @@ static inline bool manage_iplb(IplParameterBlock *iplb, bool store)
 {
     register unsigned long addr asm("0") = (unsigned long) iplb;
     register unsigned long rc asm("1") = 0;
+    unsigned long subcode = store ? 6 : 5;
 
     asm volatile ("diag %0,%2,0x308\n"
                   : "+d" (addr), "+d" (rc)
-                  : "d" (store ? 6 : 5)
+                  : "d" (subcode)
                   : "memory", "cc");
     return rc == 0x01;
 }
-- 
1.8.3.1