migration: Include migration support for machine check handling

This patch includes migration support for machine check
handling. Especially this patch blocks VM migration
requests until the machine check error handling is
complete as these errors are specific to the source
hardware and is irrelevant on the target hardware.

Signed-off-by: Aravinda Prasad <arawinda.p@gmail.com>
[Do not set FWNMI cap in post_load, now its done in .apply hook]
Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
Message-Id: <20200130184423.20519-7-ganeshgr@linux.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

1 files changed, 47 insertions, 0 deletions

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 06e295cdf1..137f5c9a33 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -46,6 +46,7 @@
 #include "migration/qemu-file-types.h"
 #include "migration/global_state.h"
 #include "migration/register.h"
+#include "migration/blocker.h"
 #include "mmu-hash64.h"
 #include "mmu-book3s-v3.h"
 #include "cpu-models.h"
@@ -1683,6 +1684,8 @@ static void spapr_machine_reset(MachineState *machine)
 
     /* Signal all vCPUs waiting on this condition */
     qemu_cond_broadcast(&spapr->mc_delivery_cond);
+
+    migrate_del_blocker(spapr->fwnmi_migration_blocker);
 }
 
 static void spapr_create_nvram(SpaprMachineState *spapr)
@@ -1965,6 +1968,42 @@ static const VMStateDescription vmstate_spapr_dtb = {
     },
 };
 
+static bool spapr_fwnmi_needed(void *opaque)
+{
+    SpaprMachineState *spapr = (SpaprMachineState *)opaque;
+
+    return spapr->guest_machine_check_addr != -1;
+}
+
+static int spapr_fwnmi_pre_save(void *opaque)
+{
+    SpaprMachineState *spapr = (SpaprMachineState *)opaque;
+
+    /*
+     * Check if machine check handling is in progress and print a
+     * warning message.
+     */
+    if (spapr->mc_status != -1) {
+        warn_report("A machine check is being handled during migration. The"
+                "handler may run and log hardware error on the destination");
+    }
+
+    return 0;
+}
+
+static const VMStateDescription vmstate_spapr_machine_check = {
+    .name = "spapr_machine_check",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .needed = spapr_fwnmi_needed,
+    .pre_save = spapr_fwnmi_pre_save,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT64(guest_machine_check_addr, SpaprMachineState),
+        VMSTATE_INT32(mc_status, SpaprMachineState),
+        VMSTATE_END_OF_LIST()
+    },
+};
+
 static const VMStateDescription vmstate_spapr = {
     .name = "spapr",
     .version_id = 3,
@@ -1999,6 +2038,7 @@ static const VMStateDescription vmstate_spapr = {
         &vmstate_spapr_cap_large_decr,
         &vmstate_spapr_cap_ccf_assist,
         &vmstate_spapr_cap_fwnmi,
+        &vmstate_spapr_machine_check,
         NULL
     }
 };
@@ -2814,6 +2854,13 @@ static void spapr_machine_init(MachineState *machine)
         spapr_create_lmb_dr_connectors(spapr);
     }
 
+    if (spapr_get_cap(spapr, SPAPR_CAP_FWNMI_MCE) == SPAPR_CAP_ON) {
+        /* Create the error string for live migration blocker */
+        error_setg(&spapr->fwnmi_migration_blocker,
+            "A machine check is being handled during migration. The handler"
+            "may run and log hardware error on the destination");
+    }
+
     /* Set up RTAS event infrastructure */
     spapr_events_init(spapr);