Merge remote-tracking branch 'remotes/borntraeger/tags/s390x-20170608' into staging

s390x: misc fixes

bunch of fixes
- reject MIDA accesses for CCWs
- cpumodel fixes
- cross-build fix for bios
- migration improvements

# gpg: Signature made Thu 08 Jun 2017 14:10:29 BST
# gpg:                using RSA key 0x117BBC80B5A61C7C
# gpg: Good signature from "Christian Borntraeger (IBM) <borntraeger@de.ibm.com>"
# Primary key fingerprint: F922 9381 A334 08F9 DBAB  FBCA 117B BC80 B5A6 1C7C

* remotes/borntraeger/tags/s390x-20170608:
  s390x/cpumodel: improve defintion search without an IBC
  s390x/cpumodel: take care of the cpuid format bit for KVM
  pc-bios/s390-ccw: use STRIP variable in Makefile
  s390x/css: fence off MIDA
  s390x/css: catch section mismatch on load

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

2 files changed, 24 insertions, 1 deletions

diff --git a/hw/s390x/css.c b/hw/s390x/css.c
index 1e2f26b65a..599805d275 100644
--- a/hw/s390x/css.c
+++ b/hw/s390x/css.c
@@ -15,6 +15,7 @@
 #include "hw/qdev.h"
 #include "qemu/error-report.h"
 #include "qemu/bitops.h"
+#include "qemu/error-report.h"
 #include "exec/address-spaces.h"
 #include "cpu.h"
 #include "hw/s390x/ioinst.h"
@@ -432,6 +433,11 @@ static int css_interpret_ccw(SubchDev *sch, hwaddr ccw_addr,
         return -EINVAL;
     }
 
+    /* We don't support MIDA. */
+    if (ccw.flags & CCW_FLAG_MIDA) {
+        return -EINVAL;
+    }
+
     if (ccw.flags & CCW_FLAG_SUSPEND) {
         return suspend_allowed ? -EINPROGRESS : -EINVAL;
     }
@@ -1800,13 +1806,26 @@ void subch_device_save(SubchDev *s, QEMUFile *f)
 int subch_device_load(SubchDev *s, QEMUFile *f)
 {
     SubchDev *old_s;
+    Error *err = NULL;
     uint16_t old_schid = s->schid;
+    uint16_t old_devno = s->devno;
     int i;
 
     s->cssid = qemu_get_byte(f);
     s->ssid = qemu_get_byte(f);
     s->schid = qemu_get_be16(f);
     s->devno = qemu_get_be16(f);
+    if (s->devno != old_devno) {
+        /* Only possible if machine < 2.7 (no css_dev_path) */
+
+        error_setg(&err, "%x != %x", old_devno,  s->devno);
+        error_append_hint(&err, "Devno mismatch, tried to load wrong section!"
+                          " Likely reason: some sequences of plug and unplug"
+                          " can break migration for machine versions prior to"
+                          " 2.7 (known design flaw).\n");
+        error_report_err(err);
+        return -EINVAL;
+    }
     /* Re-assign subch. */
     if (old_schid != s->schid) {
         old_s = channel_subsys.css[s->cssid]->sch_set[s->ssid]->sch[old_schid];
diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c
index e6a6f74be3..90d37cb9ff 100644
--- a/hw/s390x/virtio-ccw.c
+++ b/hw/s390x/virtio-ccw.c
@@ -1279,9 +1279,13 @@ static int virtio_ccw_load_config(DeviceState *d, QEMUFile *f)
     SubchDev *s = ccw_dev->sch;
     VirtIODevice *vdev = virtio_ccw_get_vdev(s);
     int len;
+    int ret;
 
     s->driver_data = dev;
-    subch_device_load(s, f);
+    ret = subch_device_load(s, f);
+    if (ret) {
+        return ret;
+    }
     /* Re-fill subch_id after loading the subchannel states.*/
     if (ck->refill_ids) {
         ck->refill_ids(ccw_dev);