On Aug 24 16:11, Philippe Mathieu-Daudé wrote:
> qemu_vfio_add_mapping() returns a pointer to an indexed entry
> in pre-allocated QEMUVFIOState::mappings[], thus can not be NULL.
> Remove the pointless check.
> 
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> ---
>  util/vfio-helpers.c | 4 ----
>  1 file changed, 4 deletions(-)
> 
> diff --git a/util/vfio-helpers.c b/util/vfio-helpers.c
> index d956866b4e9..e7909222cfd 100644
> --- a/util/vfio-helpers.c
> +++ b/util/vfio-helpers.c
> @@ -751,10 +751,6 @@ int qemu_vfio_dma_map(QEMUVFIOState *s, void *host, size_t size,
>              }
>  
>              mapping = qemu_vfio_add_mapping(s, host, size, index + 1, iova0);
> -            if (!mapping) {
> -                ret = -ENOMEM;
> -                goto out;
> -            }
>              assert(qemu_vfio_verify_mappings(s));
>              ret = qemu_vfio_do_mapping(s, host, size, iova0);
>              if (ret) {
> -- 
> 2.31.1
> 
> 

This looks OK.

But maybe it would be prudent to assert that index is within bounds of
s->mappings in qemu_vfio_add_mapping? E.g.,

   assert(index >= 0 && index < s->nr_mappings + 1);