Merge remote-tracking branch 'remotes/dgilbert/tags/pull-migration-20180724a' into staging

Migration pull for 3.0

Fixes only

# gpg: Signature made Tue 24 Jul 2018 19:31:39 BST
# gpg:                using RSA key 0516331EBC5BFDE7
# gpg: Good signature from "Dr. David Alan Gilbert (RH2) <dgilbert@redhat.com>"
# Primary key fingerprint: 45F5 C71B 4A0C B7FB 977A  9FA9 0516 331E BC5B FDE7

* remotes/dgilbert/tags/pull-migration-20180724a:
  migration: fix duplicate initialization for expected_downtime and cleanup_bh
  tests: only update last_byte when at the edge
  migration: disallow recovery for release-ram
  migration: update recv bitmap only on dest vm
  audio/hda: Fix migration
  migrate: Fix cancelling state warning
  migration: fix potential overflow in multifd send

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

4 files changed, 32 insertions, 7 deletions

diff --git a/hw/audio/hda-codec.c b/hw/audio/hda-codec.c
index 2b58c3505b..617a1c1016 100644
--- a/hw/audio/hda-codec.c
+++ b/hw/audio/hda-codec.c
@@ -786,7 +786,7 @@ static void hda_audio_reset(DeviceState *dev)
 static bool vmstate_hda_audio_stream_buf_needed(void *opaque)
 {
     HDAAudioStream *st = opaque;
-    return st->state->use_timer;
+    return st->state && st->state->use_timer;
 }
 
 static const VMStateDescription vmstate_hda_audio_stream_buf = {
diff --git a/migration/migration.c b/migration/migration.c
index 8d56d56930..b7d9854bda 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -1629,6 +1629,25 @@ static bool migrate_prepare(MigrationState *s, bool blk, bool blk_inc,
                        "paused migration");
             return false;
         }
+
+        /*
+         * Postcopy recovery won't work well with release-ram
+         * capability since release-ram will drop the page buffer as
+         * long as the page is put into the send buffer.  So if there
+         * is a network failure happened, any page buffers that have
+         * not yet reached the destination VM but have already been
+         * sent from the source VM will be lost forever.  Let's refuse
+         * the client from resuming such a postcopy migration.
+         * Luckily release-ram was designed to only be used when src
+         * and destination VMs are on the same host, so it should be
+         * fine.
+         */
+        if (migrate_release_ram()) {
+            error_setg(errp, "Postcopy recovery cannot work "
+                       "when release-ram capability is set");
+            return false;
+        }
+
         /* This is a resume, skip init status */
         return true;
     }
@@ -2877,6 +2896,7 @@ static void migration_iteration_finish(MigrationState *s)
         /* Fallthrough */
     case MIGRATION_STATUS_FAILED:
     case MIGRATION_STATUS_CANCELLED:
+    case MIGRATION_STATUS_CANCELLING:
         if (s->vm_was_running) {
             vm_start();
         } else {
@@ -3032,8 +3052,6 @@ void migrate_fd_connect(MigrationState *s, Error *error_in)
     } else {
         /* This is a fresh new migration */
         rate_limit = s->parameters.max_bandwidth / XFER_LIMIT_RATIO;
-        s->expected_downtime = s->parameters.downtime_limit;
-        s->cleanup_bh = qemu_bh_new(migrate_fd_cleanup, s);
 
         /* Notify before starting migration thread */
         notifier_list_notify(&migration_state_notifiers, s);
diff --git a/migration/ram.c b/migration/ram.c
index 52dd678092..24dea2730c 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -851,7 +851,7 @@ static void multifd_send_pages(void)
     p->pages->block = NULL;
     multifd_send_state->pages = p->pages;
     p->pages = pages;
-    transferred = pages->used * TARGET_PAGE_SIZE + p->packet_len;
+    transferred = ((uint64_t) pages->used) * TARGET_PAGE_SIZE + p->packet_len;
     ram_counters.multifd_bytes += transferred;
     ram_counters.transferred += transferred;;
     qemu_mutex_unlock(&p->mutex);
@@ -2827,8 +2827,15 @@ int ram_discard_range(const char *rbname, uint64_t start, size_t length)
         goto err;
     }
 
-    bitmap_clear(rb->receivedmap, start >> qemu_target_page_bits(),
-                 length >> qemu_target_page_bits());
+    /*
+     * On source VM, we don't need to update the received bitmap since
+     * we don't even have one.
+     */
+    if (rb->receivedmap) {
+        bitmap_clear(rb->receivedmap, start >> qemu_target_page_bits(),
+                     length >> qemu_target_page_bits());
+    }
+
     ret = ram_block_discard_range(rb, start, length);
 
 err:
diff --git a/tests/migration-test.c b/tests/migration-test.c
index 086f727b34..e079e0bdb6 100644
--- a/tests/migration-test.c
+++ b/tests/migration-test.c
@@ -300,6 +300,7 @@ static void check_guests_ram(QTestState *who)
                  * to us yet.
                  */
                 hit_edge = true;
+                last_byte = b;
             } else {
                 fprintf(stderr, "Memory content inconsistency at %x"
                                 " first_byte = %x last_byte = %x current = %x"
@@ -308,7 +309,6 @@ static void check_guests_ram(QTestState *who)
                 bad = true;
             }
         }
-        last_byte = b;
     }
     g_assert_false(bad);
 }