From: Eiichi Tsukata <de...@etsukata.com> bdrv_open_driver() allocates bs->opaque according to drv->instance_size. There is no need to allocate it and overwrite opaque in bdrv_backup_top_append().
Reproducer: $ QTEST_QEMU_BINARY=./x86_64-softmmu/qemu-system-x86_64 valgrind -q --leak-check=full tests/test-replication -p /replication/secondary/start ==29792== 24 bytes in 1 blocks are definitely lost in loss record 52 of 226 ==29792== at 0x483AB1A: calloc (vg_replace_malloc.c:762) ==29792== by 0x4B07CE0: g_malloc0 (in /usr/lib64/libglib-2.0.so.0.6000.7) ==29792== by 0x12BAB9: bdrv_open_driver (block.c:1289) ==29792== by 0x12BEA9: bdrv_new_open_driver (block.c:1359) ==29792== by 0x1D15CB: bdrv_backup_top_append (backup-top.c:190) ==29792== by 0x1CC11A: backup_job_create (backup.c:439) ==29792== by 0x1CD542: replication_start (replication.c:544) ==29792== by 0x1401B9: replication_start_all (replication.c:52) ==29792== by 0x128B50: test_secondary_start (test-replication.c:427) ... Fixes: 7df7868b9640 ("block: introduce backup-top filter driver") Signed-off-by: Eiichi Tsukata <de...@etsukata.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> Signed-off-by: Kevin Wolf <kw...@redhat.com> --- block/backup-top.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/backup-top.c b/block/backup-top.c index b8d863ff08..9aed2eb4c0 100644 --- a/block/backup-top.c +++ b/block/backup-top.c @@ -196,7 +196,7 @@ BlockDriverState *bdrv_backup_top_append(BlockDriverState *source, } top->total_sectors = source->total_sectors; - top->opaque = state = g_new0(BDRVBackupTopState, 1); + state = top->opaque; bdrv_ref(target); state->target = bdrv_attach_child(top, target, "target", &child_file, errp); -- 2.20.1