[v2,2/6] migration/colo.c: Use cpu_synchronize_all_states()

Commit Message

Lukas Straub May 20, 2020, 8:42 p.m. UTC

cpu_synchronize_all_pre_loadvm() marks all vcpus as dirty, so the
registers are loaded from CPUState before we continue running
the vm. However if we failover during checkpoint, CPUState is not
initialized and the registers are loaded with garbage. This causes
guest hangs and crashes.

Fix this by using cpu_synchronize_all_states(), which initializes
CPUState from the current cpu registers additionally to marking
the vcpus as dirty.

Signed-off-by: Lukas Straub <[e-mail]>
Reviewed-by: Dr. David Alan Gilbert <[e-mail]>
---
 migration/colo.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--
2.20.1

Patch

diff --git a/migration/colo.c b/migration/colo.c
index 09168627bc..6b2ad35aa4 100644
--- a/migration/colo.c
+++ b/migration/colo.c
@@ -696,7 +696,7 @@  static void colo_incoming_process_checkpoint(MigrationIncomingState *mis,
     }

     qemu_mutex_lock_iothread();
-    cpu_synchronize_all_pre_loadvm();
+    cpu_synchronize_all_states();
     ret = qemu_loadvm_state_main(mis->from_src_file, mis);
     qemu_mutex_unlock_iothread();