s390x/ipl: fix reboots for migration from different bios

When migrating from a different QEMU version, the start_address and
bios_start_address may differ. During migration these values are migrated
and overwrite the values that were detected by QEMU itself.

On a reboot, QEMU will reload its own BIOS, but use the migrated start
addresses, which does not work if the values differ.

Fix this by not relying on the migrated values anymore, but still
provide them during migration, so existing QEMUs continue to work.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
(cherry picked from commit bb0995468a39f14077ceaa8ed5afdca849f00c7c)
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>

diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c
index f1042002731139a10348339d5db977713c8deaa9..3173dcfdf6e3a403d2dda3f3156ede9b90d4739d 100644 (file)
--- a/hw/s390x/ipl.c
+++ b/hw/s390x/ipl.c
@@ -47,8 +47,8 @@ static const VMStateDescription vmstate_ipl = {
     .version_id = 0,
     .minimum_version_id = 0,
     .fields = (VMStateField[]) {
-        VMSTATE_UINT64(start_addr, S390IPLState),
-        VMSTATE_UINT64(bios_start_addr, S390IPLState),
+        VMSTATE_UINT64(compat_start_addr, S390IPLState),
+        VMSTATE_UINT64(compat_bios_start_addr, S390IPLState),
         VMSTATE_STRUCT(iplb, S390IPLState, 0, vmstate_iplb, IplParameterBlock),
         VMSTATE_BOOL(iplb_valid, S390IPLState),
         VMSTATE_UINT8(cssid, S390IPLState),
@@ -170,6 +170,13 @@ static void s390_ipl_realize(DeviceState *dev, Error **errp)
             stq_p(rom_ptr(INITRD_PARM_SIZE), initrd_size);
         }
     }
+    /*
+     * Don't ever use the migrated values, they could come from a different
+     * BIOS and therefore don't work. But still migrate the values, so
+     * QEMUs relying on it don't break.
+     */
+    ipl->compat_start_addr = ipl->start_addr;
+    ipl->compat_bios_start_addr = ipl->bios_start_addr;
     qemu_register_reset(qdev_reset_all_fn, dev);
 error:
     error_propagate(errp, err);

diff --git a/hw/s390x/ipl.h b/hw/s390x/ipl.h
index 6b48ed7b93a46e66763284b0de1892c9bf5d5e93..0bfb72b717b0dce20e9c4fe464e5eee1cd255375 100644 (file)
--- a/hw/s390x/ipl.h
+++ b/hw/s390x/ipl.h
@@ -33,7 +33,9 @@ struct S390IPLState {
     /*< private >*/
     DeviceState parent_obj;
     uint64_t start_addr;
+    uint64_t compat_start_addr;
     uint64_t bios_start_addr;
+    uint64_t compat_bios_start_addr;
     bool enforce_bios;
     IplParameterBlock iplb;
     bool iplb_valid;