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-rw-r--r--migration/colo.c2
-rw-r--r--migration/file.c45
-rw-r--r--migration/file.h1
-rw-r--r--migration/migration-hmp-cmds.c11
-rw-r--r--migration/migration.c121
-rw-r--r--migration/migration.h9
-rw-r--r--migration/multifd.c6
-rw-r--r--migration/options.c35
-rw-r--r--migration/options.h1
-rw-r--r--migration/postcopy-ram.c10
-rw-r--r--migration/postcopy-ram.h3
-rw-r--r--migration/ram.c4
-rw-r--r--migration/savevm.c6
13 files changed, 201 insertions, 53 deletions
diff --git a/migration/colo.c b/migration/colo.c
index f96c2ee069..6449490221 100644
--- a/migration/colo.c
+++ b/migration/colo.c
@@ -935,7 +935,7 @@ void coroutine_fn colo_incoming_co(void)
     assert(bql_locked());
     assert(migration_incoming_colo_enabled());
 
-    qemu_thread_create(&th, "COLO incoming", colo_process_incoming_thread,
+    qemu_thread_create(&th, "mig/dst/colo", colo_process_incoming_thread,
                        mis, QEMU_THREAD_JOINABLE);
 
     mis->colo_incoming_co = qemu_coroutine_self();
diff --git a/migration/file.c b/migration/file.c
index ab18ba505a..db870f2cf0 100644
--- a/migration/file.c
+++ b/migration/file.c
@@ -50,12 +50,31 @@ void file_cleanup_outgoing_migration(void)
     outgoing_args.fname = NULL;
 }
 
+static void file_enable_direct_io(int *flags)
+{
+#ifdef O_DIRECT
+    *flags |= O_DIRECT;
+#else
+    /* it should have been rejected when setting the parameter */
+    g_assert_not_reached();
+#endif
+}
+
 bool file_send_channel_create(gpointer opaque, Error **errp)
 {
     QIOChannelFile *ioc;
     int flags = O_WRONLY;
     bool ret = true;
 
+    if (migrate_direct_io()) {
+        /*
+         * Enable O_DIRECT for the secondary channels. These are used
+         * for sending ram pages and writes should be guaranteed to be
+         * aligned to at least page size.
+         */
+        file_enable_direct_io(&flags);
+    }
+
     ioc = qio_channel_file_new_path(outgoing_args.fname, flags, 0, errp);
     if (!ioc) {
         ret = false;
@@ -84,16 +103,24 @@ void file_start_outgoing_migration(MigrationState *s,
 
     trace_migration_file_outgoing(filename);
 
-    fioc = qio_channel_file_new_path(filename, O_CREAT | O_WRONLY | O_TRUNC,
-                                     0600, errp);
+    fioc = qio_channel_file_new_path(filename, O_CREAT | O_WRONLY, 0600, errp);
     if (!fioc) {
         return;
     }
 
+    if (ftruncate(fioc->fd, offset)) {
+        error_setg_errno(errp, errno,
+                         "failed to truncate migration file to offset %" PRIx64,
+                         offset);
+        object_unref(OBJECT(fioc));
+        return;
+    }
+
     outgoing_args.fname = g_strdup(filename);
 
     ioc = QIO_CHANNEL(fioc);
     if (offset && qio_channel_io_seek(ioc, offset, SEEK_SET, errp) < 0) {
+        object_unref(OBJECT(fioc));
         return;
     }
     qio_channel_set_name(ioc, "migration-file-outgoing");
@@ -109,21 +136,25 @@ static gboolean file_accept_incoming_migration(QIOChannel *ioc,
     return G_SOURCE_REMOVE;
 }
 
-void file_create_incoming_channels(QIOChannel *ioc, Error **errp)
+static void file_create_incoming_channels(QIOChannel *ioc, char *filename,
+                                          Error **errp)
 {
-    int i, fd, channels = 1;
+    int i, channels = 1;
     g_autofree QIOChannel **iocs = NULL;
+    int flags = O_RDONLY;
 
     if (migrate_multifd()) {
         channels += migrate_multifd_channels();
+        if (migrate_direct_io()) {
+            file_enable_direct_io(&flags);
+        }
     }
 
     iocs = g_new0(QIOChannel *, channels);
-    fd = QIO_CHANNEL_FILE(ioc)->fd;
     iocs[0] = ioc;
 
     for (i = 1; i < channels; i++) {
-        QIOChannelFile *fioc = qio_channel_file_new_dupfd(fd, errp);
+        QIOChannelFile *fioc = qio_channel_file_new_path(filename, flags, 0, errp);
 
         if (!fioc) {
             while (i) {
@@ -163,7 +194,7 @@ void file_start_incoming_migration(FileMigrationArgs *file_args, Error **errp)
         return;
     }
 
-    file_create_incoming_channels(QIO_CHANNEL(fioc), errp);
+    file_create_incoming_channels(QIO_CHANNEL(fioc), filename, errp);
 }
 
 int file_write_ramblock_iov(QIOChannel *ioc, const struct iovec *iov,
diff --git a/migration/file.h b/migration/file.h
index 7699c04677..9f71e87f74 100644
--- a/migration/file.h
+++ b/migration/file.h
@@ -20,7 +20,6 @@ void file_start_outgoing_migration(MigrationState *s,
 int file_parse_offset(char *filespec, uint64_t *offsetp, Error **errp);
 void file_cleanup_outgoing_migration(void);
 bool file_send_channel_create(gpointer opaque, Error **errp);
-void file_create_incoming_channels(QIOChannel *ioc, Error **errp);
 int file_write_ramblock_iov(QIOChannel *ioc, const struct iovec *iov,
                             int niov, RAMBlock *block, Error **errp);
 int multifd_file_recv_data(MultiFDRecvParams *p, Error **errp);
diff --git a/migration/migration-hmp-cmds.c b/migration/migration-hmp-cmds.c
index 9f0e8029e0..7d608d26e1 100644
--- a/migration/migration-hmp-cmds.c
+++ b/migration/migration-hmp-cmds.c
@@ -351,6 +351,13 @@ void hmp_info_migrate_parameters(Monitor *mon, const QDict *qdict)
         monitor_printf(mon, "%s: %s\n",
             MigrationParameter_str(MIGRATION_PARAMETER_MODE),
             qapi_enum_lookup(&MigMode_lookup, params->mode));
+
+        if (params->has_direct_io) {
+            monitor_printf(mon, "%s: %s\n",
+                           MigrationParameter_str(
+                               MIGRATION_PARAMETER_DIRECT_IO),
+                           params->direct_io ? "on" : "off");
+        }
     }
 
     qapi_free_MigrationParameters(params);
@@ -624,6 +631,10 @@ void hmp_migrate_set_parameter(Monitor *mon, const QDict *qdict)
         p->has_mode = true;
         visit_type_MigMode(v, param, &p->mode, &err);
         break;
+    case MIGRATION_PARAMETER_DIRECT_IO:
+        p->has_direct_io = true;
+        visit_type_bool(v, param, &p->direct_io, &err);
+        break;
     default:
         assert(0);
     }
diff --git a/migration/migration.c b/migration/migration.c
index e1b269624c..3dea06d577 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -155,6 +155,16 @@ static bool migration_needs_seekable_channel(void)
     return migrate_mapped_ram();
 }
 
+static bool migration_needs_extra_fds(void)
+{
+    /*
+     * When doing direct-io, multifd requires two different,
+     * non-duplicated file descriptors so we can use one of them for
+     * unaligned IO.
+     */
+    return migrate_multifd() && migrate_direct_io();
+}
+
 static bool transport_supports_seeking(MigrationAddress *addr)
 {
     if (addr->transport == MIGRATION_ADDRESS_TYPE_FILE) {
@@ -164,6 +174,12 @@ static bool transport_supports_seeking(MigrationAddress *addr)
     return false;
 }
 
+static bool transport_supports_extra_fds(MigrationAddress *addr)
+{
+    /* file: works because QEMU can open it multiple times */
+    return addr->transport == MIGRATION_ADDRESS_TYPE_FILE;
+}
+
 static bool
 migration_channels_and_transport_compatible(MigrationAddress *addr,
                                             Error **errp)
@@ -180,6 +196,13 @@ migration_channels_and_transport_compatible(MigrationAddress *addr,
         return false;
     }
 
+    if (migration_needs_extra_fds() &&
+        !transport_supports_extra_fds(addr)) {
+        error_setg(errp,
+                   "Migration requires a transport that allows for extra fds (e.g. file)");
+        return false;
+    }
+
     return true;
 }
 
@@ -390,7 +413,7 @@ void migration_incoming_state_destroy(void)
     yank_unregister_instance(MIGRATION_YANK_INSTANCE);
 }
 
-static void migrate_generate_event(int new_state)
+static void migrate_generate_event(MigrationStatus new_state)
 {
     if (migrate_events()) {
         qapi_event_send_migration(new_state);
@@ -595,6 +618,29 @@ bool migrate_uri_parse(const char *uri, MigrationChannel **channel,
     return true;
 }
 
+static bool
+migration_incoming_state_setup(MigrationIncomingState *mis, Error **errp)
+{
+    MigrationStatus current = mis->state;
+
+    if (current == MIGRATION_STATUS_POSTCOPY_PAUSED) {
+        /*
+         * Incoming postcopy migration will stay in PAUSED state even if
+         * reconnection happened.
+         */
+        return true;
+    }
+
+    if (current != MIGRATION_STATUS_NONE) {
+        error_setg(errp, "Illegal migration incoming state: %s",
+                   MigrationStatus_str(current));
+        return false;
+    }
+
+    migrate_set_state(&mis->state, current, MIGRATION_STATUS_SETUP);
+    return true;
+}
+
 static void qemu_start_incoming_migration(const char *uri, bool has_channels,
                                           MigrationChannelList *channels,
                                           Error **errp)
@@ -633,8 +679,9 @@ static void qemu_start_incoming_migration(const char *uri, bool has_channels,
         return;
     }
 
-    migrate_set_state(&mis->state, MIGRATION_STATUS_NONE,
-                      MIGRATION_STATUS_SETUP);
+    if (!migration_incoming_state_setup(mis, errp)) {
+        return;
+    }
 
     if (addr->transport == MIGRATION_ADDRESS_TYPE_SOCKET) {
         SocketAddress *saddr = &addr->u.socket;
@@ -1070,6 +1117,7 @@ bool migration_is_setup_or_active(void)
     case MIGRATION_STATUS_ACTIVE:
     case MIGRATION_STATUS_POSTCOPY_ACTIVE:
     case MIGRATION_STATUS_POSTCOPY_PAUSED:
+    case MIGRATION_STATUS_POSTCOPY_RECOVER_SETUP:
     case MIGRATION_STATUS_POSTCOPY_RECOVER:
     case MIGRATION_STATUS_SETUP:
     case MIGRATION_STATUS_PRE_SWITCHOVER:
@@ -1092,6 +1140,7 @@ bool migration_is_running(void)
     case MIGRATION_STATUS_ACTIVE:
     case MIGRATION_STATUS_POSTCOPY_ACTIVE:
     case MIGRATION_STATUS_POSTCOPY_PAUSED:
+    case MIGRATION_STATUS_POSTCOPY_RECOVER_SETUP:
     case MIGRATION_STATUS_POSTCOPY_RECOVER:
     case MIGRATION_STATUS_SETUP:
     case MIGRATION_STATUS_PRE_SWITCHOVER:
@@ -1229,6 +1278,7 @@ static void fill_source_migration_info(MigrationInfo *info)
     case MIGRATION_STATUS_PRE_SWITCHOVER:
     case MIGRATION_STATUS_DEVICE:
     case MIGRATION_STATUS_POSTCOPY_PAUSED:
+    case MIGRATION_STATUS_POSTCOPY_RECOVER_SETUP:
     case MIGRATION_STATUS_POSTCOPY_RECOVER:
         /* TODO add some postcopy stats */
         populate_time_info(info, s);
@@ -1273,8 +1323,6 @@ static void fill_destination_migration_info(MigrationInfo *info)
     }
 
     switch (mis->state) {
-    case MIGRATION_STATUS_NONE:
-        return;
     case MIGRATION_STATUS_SETUP:
     case MIGRATION_STATUS_CANCELLING:
     case MIGRATION_STATUS_CANCELLED:
@@ -1290,6 +1338,8 @@ static void fill_destination_migration_info(MigrationInfo *info)
         info->has_status = true;
         fill_destination_postcopy_migration_info(info);
         break;
+    default:
+        return;
     }
     info->status = mis->state;
 
@@ -1337,7 +1387,8 @@ void qmp_migrate_start_postcopy(Error **errp)
 
 /* shared migration helpers */
 
-void migrate_set_state(int *state, int old_state, int new_state)
+void migrate_set_state(MigrationStatus *state, MigrationStatus old_state,
+                       MigrationStatus new_state)
 {
     assert(new_state < MIGRATION_STATUS__MAX);
     if (qatomic_cmpxchg(state, old_state, new_state) == old_state) {
@@ -1434,9 +1485,30 @@ static void migrate_error_free(MigrationState *s)
 
 static void migrate_fd_error(MigrationState *s, const Error *error)
 {
+    MigrationStatus current = s->state;
+    MigrationStatus next;
+
     assert(s->to_dst_file == NULL);
-    migrate_set_state(&s->state, MIGRATION_STATUS_SETUP,
-                      MIGRATION_STATUS_FAILED);
+
+    switch (current) {
+    case MIGRATION_STATUS_SETUP:
+        next = MIGRATION_STATUS_FAILED;
+        break;
+    case MIGRATION_STATUS_POSTCOPY_RECOVER_SETUP:
+        /* Never fail a postcopy migration; switch back to PAUSED instead */
+        next = MIGRATION_STATUS_POSTCOPY_PAUSED;
+        break;
+    default:
+        /*
+         * This really shouldn't happen. Just be careful to not crash a VM
+         * just for this.  Instead, dump something.
+         */
+        error_report("%s: Illegal migration status (%s) detected",
+                     __func__, MigrationStatus_str(current));
+        return;
+    }
+
+    migrate_set_state(&s->state, current, next);
     migrate_set_error(s, error);
 }
 
@@ -1537,6 +1609,7 @@ bool migration_in_postcopy(void)
     switch (s->state) {
     case MIGRATION_STATUS_POSTCOPY_ACTIVE:
     case MIGRATION_STATUS_POSTCOPY_PAUSED:
+    case MIGRATION_STATUS_POSTCOPY_RECOVER_SETUP:
     case MIGRATION_STATUS_POSTCOPY_RECOVER:
         return true;
     default:
@@ -1544,7 +1617,7 @@ bool migration_in_postcopy(void)
     }
 }
 
-bool migration_postcopy_is_alive(int state)
+bool migration_postcopy_is_alive(MigrationStatus state)
 {
     switch (state) {
     case MIGRATION_STATUS_POSTCOPY_ACTIVE:
@@ -1589,20 +1662,9 @@ bool migration_is_idle(void)
     case MIGRATION_STATUS_COMPLETED:
     case MIGRATION_STATUS_FAILED:
         return true;
-    case MIGRATION_STATUS_SETUP:
-    case MIGRATION_STATUS_CANCELLING:
-    case MIGRATION_STATUS_ACTIVE:
-    case MIGRATION_STATUS_POSTCOPY_ACTIVE:
-    case MIGRATION_STATUS_COLO:
-    case MIGRATION_STATUS_PRE_SWITCHOVER:
-    case MIGRATION_STATUS_DEVICE:
-    case MIGRATION_STATUS_WAIT_UNPLUG:
+    default:
         return false;
-    case MIGRATION_STATUS__MAX:
-        g_assert_not_reached();
     }
-
-    return false;
 }
 
 bool migration_is_active(void)
@@ -1935,6 +1997,9 @@ static bool migrate_prepare(MigrationState *s, bool resume, Error **errp)
             return false;
         }
 
+        migrate_set_state(&s->state, MIGRATION_STATUS_POSTCOPY_PAUSED,
+                          MIGRATION_STATUS_POSTCOPY_RECOVER_SETUP);
+
         /* This is a resume, skip init status */
         return true;
     }
@@ -2408,7 +2473,7 @@ static int open_return_path_on_source(MigrationState *ms)
 
     trace_open_return_path_on_source();
 
-    qemu_thread_create(&ms->rp_state.rp_thread, "return path",
+    qemu_thread_create(&ms->rp_state.rp_thread, "mig/src/rp-thr",
                        source_return_path_thread, ms, QEMU_THREAD_JOINABLE);
     ms->rp_state.rp_thread_created = true;
 
@@ -2967,9 +3032,9 @@ static MigThrError postcopy_pause(MigrationState *s)
          * We wait until things fixed up. Then someone will setup the
          * status back for us.
          */
-        while (s->state == MIGRATION_STATUS_POSTCOPY_PAUSED) {
+        do {
             qemu_sem_wait(&s->postcopy_pause_sem);
-        }
+        } while (postcopy_is_paused(s->state));
 
         if (s->state == MIGRATION_STATUS_POSTCOPY_RECOVER) {
             /* Woken up by a recover procedure. Give it a shot */
@@ -3665,7 +3730,7 @@ void migrate_fd_connect(MigrationState *s, Error *error_in)
 {
     Error *local_err = NULL;
     uint64_t rate_limit;
-    bool resume = s->state == MIGRATION_STATUS_POSTCOPY_PAUSED;
+    bool resume = (s->state == MIGRATION_STATUS_POSTCOPY_RECOVER_SETUP);
     int ret;
 
     /*
@@ -3732,7 +3797,7 @@ void migrate_fd_connect(MigrationState *s, Error *error_in)
 
     if (resume) {
         /* Wakeup the main migration thread to do the recovery */
-        migrate_set_state(&s->state, MIGRATION_STATUS_POSTCOPY_PAUSED,
+        migrate_set_state(&s->state, MIGRATION_STATUS_POSTCOPY_RECOVER_SETUP,
                           MIGRATION_STATUS_POSTCOPY_RECOVER);
         qemu_sem_post(&s->postcopy_pause_sem);
         return;
@@ -3747,10 +3812,10 @@ void migrate_fd_connect(MigrationState *s, Error *error_in)
     }
 
     if (migrate_background_snapshot()) {
-        qemu_thread_create(&s->thread, "bg_snapshot",
+        qemu_thread_create(&s->thread, "mig/snapshot",
                 bg_migration_thread, s, QEMU_THREAD_JOINABLE);
     } else {
-        qemu_thread_create(&s->thread, "live_migration",
+        qemu_thread_create(&s->thread, "mig/src/main",
                 migration_thread, s, QEMU_THREAD_JOINABLE);
     }
     s->migration_thread_running = true;
diff --git a/migration/migration.h b/migration/migration.h
index 6af01362d4..38aa1402d5 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -160,7 +160,7 @@ struct MigrationIncomingState {
     /* PostCopyFD's for external userfaultfds & handlers of shared memory */
     GArray   *postcopy_remote_fds;
 
-    int state;
+    MigrationStatus state;
 
     /*
      * The incoming migration coroutine, non-NULL during qemu_loadvm_state().
@@ -301,7 +301,7 @@ struct MigrationState {
     /* params from 'migrate-set-parameters' */
     MigrationParameters parameters;
 
-    int state;
+    MigrationStatus state;
 
     /* State related to return path */
     struct {
@@ -459,7 +459,8 @@ struct MigrationState {
     bool rdma_migration;
 };
 
-void migrate_set_state(int *state, int old_state, int new_state);
+void migrate_set_state(MigrationStatus *state, MigrationStatus old_state,
+                       MigrationStatus new_state);
 
 void migration_fd_process_incoming(QEMUFile *f);
 void migration_ioc_process_incoming(QIOChannel *ioc, Error **errp);
@@ -479,7 +480,7 @@ int migrate_init(MigrationState *s, Error **errp);
 bool migration_is_blocked(Error **errp);
 /* True if outgoing migration has entered postcopy phase */
 bool migration_in_postcopy(void);
-bool migration_postcopy_is_alive(int state);
+bool migration_postcopy_is_alive(MigrationStatus state);
 MigrationState *migrate_get_current(void);
 bool migration_has_failed(MigrationState *);
 bool migrate_mode_is_cpr(MigrationState *);
diff --git a/migration/multifd.c b/migration/multifd.c
index d82885fdbb..0b4cbaddfe 100644
--- a/migration/multifd.c
+++ b/migration/multifd.c
@@ -1069,7 +1069,7 @@ static bool multifd_tls_channel_connect(MultiFDSendParams *p,
     args->p = p;
 
     p->tls_thread_created = true;
-    qemu_thread_create(&p->tls_thread, "multifd-tls-handshake-worker",
+    qemu_thread_create(&p->tls_thread, "mig/src/tls",
                        multifd_tls_handshake_thread, args,
                        QEMU_THREAD_JOINABLE);
     return true;
@@ -1190,7 +1190,7 @@ bool multifd_send_setup(void)
             p->packet->magic = cpu_to_be32(MULTIFD_MAGIC);
             p->packet->version = cpu_to_be32(MULTIFD_VERSION);
         }
-        p->name = g_strdup_printf("multifdsend_%d", i);
+        p->name = g_strdup_printf("mig/src/send_%d", i);
         p->page_size = qemu_target_page_size();
         p->page_count = page_count;
         p->write_flags = 0;
@@ -1604,7 +1604,7 @@ int multifd_recv_setup(Error **errp)
                 + sizeof(uint64_t) * page_count;
             p->packet = g_malloc0(p->packet_len);
         }
-        p->name = g_strdup_printf("multifdrecv_%d", i);
+        p->name = g_strdup_printf("mig/dst/recv_%d", i);
         p->normal = g_new0(ram_addr_t, page_count);
         p->zero = g_new0(ram_addr_t, page_count);
         p->page_count = page_count;
diff --git a/migration/options.c b/migration/options.c
index 5ab5b6d85d..645f55003d 100644
--- a/migration/options.c
+++ b/migration/options.c
@@ -702,6 +702,25 @@ bool migrate_cpu_throttle_tailslow(void)
     return s->parameters.cpu_throttle_tailslow;
 }
 
+bool migrate_direct_io(void)
+{
+    MigrationState *s = migrate_get_current();
+
+    /*
+     * O_DIRECT is only supported with mapped-ram and multifd.
+     *
+     * mapped-ram is needed because filesystems impose restrictions on
+     * O_DIRECT IO alignment (see MAPPED_RAM_FILE_OFFSET_ALIGNMENT).
+     *
+     * multifd is needed to keep the unaligned portion of the stream
+     * isolated to the main migration thread while multifd channels
+     * process the aligned data with O_DIRECT enabled.
+     */
+    return s->parameters.direct_io &&
+        s->capabilities[MIGRATION_CAPABILITY_MAPPED_RAM] &&
+        s->capabilities[MIGRATION_CAPABILITY_MULTIFD];
+}
+
 uint64_t migrate_downtime_limit(void)
 {
     MigrationState *s = migrate_get_current();
@@ -905,6 +924,8 @@ MigrationParameters *qmp_query_migrate_parameters(Error **errp)
     params->mode = s->parameters.mode;
     params->has_zero_page_detection = true;
     params->zero_page_detection = s->parameters.zero_page_detection;
+    params->has_direct_io = true;
+    params->direct_io = s->parameters.direct_io;
 
     return params;
 }
@@ -937,6 +958,7 @@ void migrate_params_init(MigrationParameters *params)
     params->has_vcpu_dirty_limit = true;
     params->has_mode = true;
     params->has_zero_page_detection = true;
+    params->has_direct_io = true;
 }
 
 /*
@@ -1110,6 +1132,11 @@ bool migrate_params_check(MigrationParameters *params, Error **errp)
         return false;
     }
 
+    if (params->has_direct_io && params->direct_io && !qemu_has_direct_io()) {
+        error_setg(errp, "No build-time support for direct-io");
+        return false;
+    }
+
     return true;
 }
 
@@ -1216,6 +1243,10 @@ static void migrate_params_test_apply(MigrateSetParameters *params,
     if (params->has_zero_page_detection) {
         dest->zero_page_detection = params->zero_page_detection;
     }
+
+    if (params->has_direct_io) {
+        dest->direct_io = params->direct_io;
+    }
 }
 
 static void migrate_params_apply(MigrateSetParameters *params, Error **errp)
@@ -1341,6 +1372,10 @@ static void migrate_params_apply(MigrateSetParameters *params, Error **errp)
     if (params->has_zero_page_detection) {
         s->parameters.zero_page_detection = params->zero_page_detection;
     }
+
+    if (params->has_direct_io) {
+        s->parameters.direct_io = params->direct_io;
+    }
 }
 
 void qmp_migrate_set_parameters(MigrateSetParameters *params, Error **errp)
diff --git a/migration/options.h b/migration/options.h
index 4b21cc2669..a2397026db 100644
--- a/migration/options.h
+++ b/migration/options.h
@@ -69,6 +69,7 @@ uint32_t migrate_checkpoint_delay(void);
 uint8_t migrate_cpu_throttle_increment(void);
 uint8_t migrate_cpu_throttle_initial(void);
 bool migrate_cpu_throttle_tailslow(void);
+bool migrate_direct_io(void);
 uint64_t migrate_downtime_limit(void);
 uint8_t migrate_max_cpu_throttle(void);
 uint64_t migrate_max_bandwidth(void);
diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c
index 3419779548..1c374b7ea1 100644
--- a/migration/postcopy-ram.c
+++ b/migration/postcopy-ram.c
@@ -1238,7 +1238,7 @@ int postcopy_ram_incoming_setup(MigrationIncomingState *mis)
         return -1;
     }
 
-    postcopy_thread_create(mis, &mis->fault_thread, "fault-default",
+    postcopy_thread_create(mis, &mis->fault_thread, "mig/dst/fault",
                            postcopy_ram_fault_thread, QEMU_THREAD_JOINABLE);
     mis->have_fault_thread = true;
 
@@ -1258,7 +1258,7 @@ int postcopy_ram_incoming_setup(MigrationIncomingState *mis)
          * This thread needs to be created after the temp pages because
          * it'll fetch RAM_CHANNEL_POSTCOPY PostcopyTmpPage immediately.
          */
-        postcopy_thread_create(mis, &mis->postcopy_prio_thread, "fault-fast",
+        postcopy_thread_create(mis, &mis->postcopy_prio_thread, "mig/dst/preempt",
                                postcopy_preempt_thread, QEMU_THREAD_JOINABLE);
         mis->preempt_thread_status = PREEMPT_THREAD_CREATED;
     }
@@ -1770,3 +1770,9 @@ void *postcopy_preempt_thread(void *opaque)
 
     return NULL;
 }
+
+bool postcopy_is_paused(MigrationStatus status)
+{
+    return status == MIGRATION_STATUS_POSTCOPY_PAUSED ||
+        status == MIGRATION_STATUS_POSTCOPY_RECOVER_SETUP;
+}
diff --git a/migration/postcopy-ram.h b/migration/postcopy-ram.h
index ecae941211..a6df1b2811 100644
--- a/migration/postcopy-ram.h
+++ b/migration/postcopy-ram.h
@@ -13,6 +13,8 @@
 #ifndef QEMU_POSTCOPY_RAM_H
 #define QEMU_POSTCOPY_RAM_H
 
+#include "qapi/qapi-types-migration.h"
+
 /* Return true if the host supports everything we need to do postcopy-ram */
 bool postcopy_ram_supported_by_host(MigrationIncomingState *mis,
                                     Error **errp);
@@ -193,5 +195,6 @@ enum PostcopyChannels {
 void postcopy_preempt_new_channel(MigrationIncomingState *mis, QEMUFile *file);
 void postcopy_preempt_setup(MigrationState *s);
 int postcopy_preempt_establish_channel(MigrationState *s);
+bool postcopy_is_paused(MigrationStatus status);
 
 #endif
diff --git a/migration/ram.c b/migration/ram.c
index ceea586b06..edec1a2d07 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -3300,10 +3300,6 @@ static int ram_save_complete(QEMUFile *f, void *opaque)
         }
     }
 
-    if (migrate_multifd() && !migrate_multifd_flush_after_each_section() &&
-        !migrate_mapped_ram()) {
-        qemu_put_be64(f, RAM_SAVE_FLAG_MULTIFD_FLUSH);
-    }
     qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
     return qemu_fflush(f);
 }
diff --git a/migration/savevm.c b/migration/savevm.c
index c621f2359b..deb57833f8 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -2129,7 +2129,7 @@ static int loadvm_postcopy_handle_listen(MigrationIncomingState *mis)
     }
 
     mis->have_listen_thread = true;
-    postcopy_thread_create(mis, &mis->listen_thread, "postcopy/listen",
+    postcopy_thread_create(mis, &mis->listen_thread, "mig/dst/listen",
                            postcopy_ram_listen_thread, QEMU_THREAD_DETACHED);
     trace_loadvm_postcopy_handle_listen("return");
 
@@ -2864,9 +2864,9 @@ static bool postcopy_pause_incoming(MigrationIncomingState *mis)
     error_report("Detected IO failure for postcopy. "
                  "Migration paused.");
 
-    while (mis->state == MIGRATION_STATUS_POSTCOPY_PAUSED) {
+    do {
         qemu_sem_wait(&mis->postcopy_pause_sem_dst);
-    }
+    } while (postcopy_is_paused(mis->state));
 
     trace_postcopy_pause_incoming_continued();