Commit 9538cbbec7 for qemu.org

commit 9538cbbec7f50fa951ad8041bd9e74f9272ddb02
Author: Marc-André Lureau <marcandre.lureau@redhat.com>
Date:   Thu Oct 22 15:42:09 2026 +0400

    migration: tolerate NULL ram_block in vmstate_unregister_ram()

    Treat a missing RAMBlock as nothing to unregister.
    qemu_ram_unset_idstr() already accepts a NULL block.

    Tested-by: Gerd Hoffmann <kraxel@redhat.com>
    Acked-by: Gerd Hoffmann <kraxel@redhat.com>
    Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>

diff --git a/migration/savevm.c b/migration/savevm.c
index 4b590ea672..fe94ba96e4 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -3610,6 +3610,9 @@ void vmstate_register_ram(MemoryRegion *mr, DeviceState *dev)

 void vmstate_unregister_ram(MemoryRegion *mr, DeviceState *dev)
 {
+    if (!mr->ram_block) {
+        return;
+    }
     qemu_ram_unset_idstr(mr->ram_block);
     qemu_ram_unset_migratable(mr->ram_block);
     ram_block_del_cpr_blocker(mr->ram_block);