[PULL,26/38] migration: Stop migration immediately in RDMA error paths

Commit Message

Juan Quintela Oct. 31, 2023, 9:01 a.m. UTC

From: Peter Xu <[e-mail]>

In multiple places, RDMA errors are handled in a strange way, where it only
sets qemu_file_set_error() but not stop the migration immediately.

It's not obvious what will happen later if there is already an error.  Make
all such failures stop migration immediately.

Cc: Zhijian Li (Fujitsu) <[e-mail]>
Cc: Markus Armbruster <[e-mail]>
Cc: Juan Quintela <[e-mail]>
Cc: Fabiano Rosas <[e-mail]>
Reported-by: Thomas Huth <[e-mail]>
Signed-off-by: Peter Xu <[e-mail]>
Reviewed-by: Juan Quintela <[e-mail]>
Reviewed-by: Fabiano Rosas <[e-mail]>
Signed-off-by: Juan Quintela <[e-mail]>
Message-ID: <[e-mail]>
---
 migration/ram.c | 21 ++++++++++-----------
 1 file changed, 10 insertions(+), 11 deletions(-)

Patch

diff --git a/migration/ram.c b/migration/ram.c
index 024dedb6b1..20e6153114 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -2973,11 +2973,13 @@  static int ram_save_setup(QEMUFile *f, void *opaque)
     ret = rdma_registration_start(f, RAM_CONTROL_SETUP);
     if (ret < 0) {
         qemu_file_set_error(f, ret);
+        return ret;
     }
 
     ret = rdma_registration_stop(f, RAM_CONTROL_SETUP);
     if (ret < 0) {
         qemu_file_set_error(f, ret);
+        return ret;
     }
 
     migration_ops = g_malloc0(sizeof(MigrationOps));
@@ -3043,6 +3045,7 @@  static int ram_save_iterate(QEMUFile *f, void *opaque)
         ret = rdma_registration_start(f, RAM_CONTROL_ROUND);
         if (ret < 0) {
             qemu_file_set_error(f, ret);
+            goto out;
         }
 
         t0 = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
@@ -3147,8 +3150,6 @@  static int ram_save_complete(QEMUFile *f, void *opaque)
     rs->last_stage = !migration_in_colo_state();
 
     WITH_RCU_READ_LOCK_GUARD() {
-        int rdma_reg_ret;
-
         if (!migration_in_postcopy()) {
             migration_bitmap_sync_precopy(rs, true);
         }
@@ -3156,6 +3157,7 @@  static int ram_save_complete(QEMUFile *f, void *opaque)
         ret = rdma_registration_start(f, RAM_CONTROL_FINISH);
         if (ret < 0) {
             qemu_file_set_error(f, ret);
+            return ret;
         }
 
         /* try transferring iterative blocks of memory */
@@ -3171,24 +3173,21 @@  static int ram_save_complete(QEMUFile *f, void *opaque)
                 break;
             }
             if (pages < 0) {
-                ret = pages;
-                break;
+                qemu_mutex_unlock(&rs->bitmap_mutex);
+                return pages;
             }
         }
         qemu_mutex_unlock(&rs->bitmap_mutex);
 
         compress_flush_data();
 
-        rdma_reg_ret = rdma_registration_stop(f, RAM_CONTROL_FINISH);
-        if (rdma_reg_ret < 0) {
-            qemu_file_set_error(f, rdma_reg_ret);
+        ret = rdma_registration_stop(f, RAM_CONTROL_FINISH);
+        if (ret < 0) {
+            qemu_file_set_error(f, ret);
+            return ret;
         }
     }
 
-    if (ret < 0) {
-        return ret;
-    }
-
     ret = multifd_send_sync_main(rs->pss[RAM_CHANNEL_PRECOPY].pss_channel);
     if (ret < 0) {
         return ret;