On Tue, 09/05 10:44, Kevin Wolf wrote: > Am 30.08.2017 um 12:06 hat Fam Zheng geschrieben: > > This fixes the assertion due to op blockers added by BMDS: > > > > block.c:3248: bdrv_delete: Assertion `bdrv_op_blocker_is_empty(bs)' failed. > > > > Reproducer: simply start block migration and quit QEMU before it ends. > > > > Cc: qemu-sta...@nongnu.org > > Signed-off-by: Fam Zheng <f...@redhat.com> > > --- > > block.c | 2 ++ > > migration/block.c | 2 +- > > migration/block.h | 1 + > > stubs/Makefile.objs | 1 + > > stubs/block-migration.c | 6 ++++++ > > 5 files changed, 11 insertions(+), 1 deletion(-) > > create mode 100644 stubs/block-migration.c > > > > diff --git a/block.c b/block.c > > index 3308814bba..508a57274d 100644 > > --- a/block.c > > +++ b/block.c > > @@ -43,6 +43,7 @@ > > #include "qemu/cutils.h" > > #include "qemu/id.h" > > #include "qapi/util.h" > > +#include "migration/block.h" > > > > #ifdef CONFIG_BSD > > #include <sys/ioctl.h> > > @@ -3111,6 +3112,7 @@ static void bdrv_close(BlockDriverState *bs) > > > > void bdrv_close_all(void) > > { > > + block_migration_cleanup_bmds(); > > block_job_cancel_sync_all(); > > nbd_export_close_all(); > > This is before bdrv_drain_all(). Can't we still have a block migration > request in flight, whose callback will then dereference a stale pointer?
You're right, bdrv_drain_all should be called first. Fam