exp->common.blk cannot be NULL, nbd_export_delete() is only called from
blk_exp_unref() and in turn that can only happen after blk_exp_add()
has asserted exp->blk != NULL.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 nbd/server.c | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/nbd/server.c b/nbd/server.c
index 4305d4f0edf3..cb41b56095ee 100644
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -1847,15 +1847,13 @@ static void nbd_export_delete(BlockExport *blk_exp)
     g_free(exp->description);
     exp->description = NULL;
 
-    if (exp->common.blk) {
-        if (exp->eject_notifier_blk) {
-            notifier_remove(&exp->eject_notifier);
-            blk_unref(exp->eject_notifier_blk);
-        }
-        blk_remove_aio_context_notifier(exp->common.blk, blk_aio_attached,
-                                        blk_aio_detach, exp);
-        blk_set_disable_request_queuing(exp->common.blk, false);
+    if (exp->eject_notifier_blk) {
+        notifier_remove(&exp->eject_notifier);
+        blk_unref(exp->eject_notifier_blk);
     }
+    blk_remove_aio_context_notifier(exp->common.blk, blk_aio_attached,
+                                    blk_aio_detach, exp);
+    blk_set_disable_request_queuing(exp->common.blk, false);
 
     for (i = 0; i < exp->nr_export_bitmaps; i++) {
         bdrv_dirty_bitmap_set_busy(exp->export_bitmaps[i], false);
-- 
2.39.2

On Wed, Apr 05, 2023 at 12:16:34PM +0200, Paolo Bonzini wrote:
> exp->common.blk cannot be NULL, nbd_export_delete() is only called from
> blk_exp_unref() and in turn that can only happen after blk_exp_add()
> has asserted exp->blk != NULL.

Commit message is a bit imprecise (maybe due to refactoring in the
meantime?): drv->delete is only called from blk_exp_delete_bh(), but
that in turn is indeed only called from blk_exp_unref(), so the logic
is sound.

> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>  nbd/server.c | 14 ++++++--------
>  1 file changed, 6 insertions(+), 8 deletions(-)

Reviewed-by: Eric Blake <eblake@redhat.com>

As this is only removal of a useless conditional, it can wait for 8.1.

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org

On Wed, Apr 05, 2023 at 07:54:50AM -0500, Eric Blake wrote:
> On Wed, Apr 05, 2023 at 12:16:34PM +0200, Paolo Bonzini wrote:
> > exp->common.blk cannot be NULL, nbd_export_delete() is only called from
> > blk_exp_unref() and in turn that can only happen after blk_exp_add()
> > has asserted exp->blk != NULL.
> 
> Commit message is a bit imprecise (maybe due to refactoring in the
> meantime?): drv->delete is only called from blk_exp_delete_bh(), but
> that in turn is indeed only called from blk_exp_unref(), so the logic
> is sound.
> 
> > 
> > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> > ---
> >  nbd/server.c | 14 ++++++--------
> >  1 file changed, 6 insertions(+), 8 deletions(-)
> 
> Reviewed-by: Eric Blake <eblake@redhat.com>
> 
> As this is only removal of a useless conditional, it can wait for 8.1.

Thanks; queued on my NBD tree for a pull request this week.

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org