As gcc luckily noted:
On Tue, Aug 20, 2024 at 03:33:20PM +0800, Xuan Zhuo wrote:
> @@ -1617,23 +1617,24 @@ static void detach_buf_packed(struct vring_virtqueue
> *vq,
> }
>
> if (vq->indirect) {
> + struct vring_desc_extra *extra;
> u32 len;
>
> /* Free the indirect table, if any, now that it's unmapped. */
> - desc = state->indir_desc;
> - if (!desc)
desc is no longer initialized here
> + extra = state->indir;
> + if (!extra)
> return;
>
> if (vring_need_unmap_buffer(vq)) {
> len = vq->packed.desc_extra[id].len;
> for (i = 0; i < len / sizeof(struct vring_packed_desc);
> i++)
> - vring_unmap_desc_packed(vq, &desc[i]);
> + vring_unmap_extra_packed(vq, &extra[i]);
> }
> kfree(desc);
but freed here
> - state->indir_desc = NULL;
> + state->indir = NULL;
> } else if (ctx) {
> - *ctx = state->indir_desc;
> + *ctx = state->indir;
> }
> }
It seems unlikely this was always 0 on all paths with even
a small amount of stress, so now I question how this was tested.
Besides, do not ignore compiler warnings, and do not tweak code
to just make compiler shut up - they are your friend.
>
> --
> 2.32.0.3.g01195cf9f