Re: [Qemu-devel] [PATCH] virtio-blk: Check return value of blk_aio_ioctl

[Kevin Wolf <kwolf@redhat.com>]

Am 17.02.2015 um 04:29 hat Fam Zheng geschrieben:
> Since commit 1dc936aa84 (virtio-blk: Use blk_aio_ioctl) we silently lose
> the request if blk_aio_ioctl returns NULL (not implemented).
> 
> Fix it by directly returning VIRTIO_BLK_S_UNSUPP as we used to do.
> 
> Signed-off-by: Fam Zheng <famz@redhat.com>
> ---
>  hw/block/virtio-blk.c | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
> index 1a8a176..c7c8f20 100644
> --- a/hw/block/virtio-blk.c
> +++ b/hw/block/virtio-blk.c
> @@ -197,6 +197,7 @@ static int virtio_blk_handle_scsi_req(VirtIOBlockReq *req)
>      VirtIODevice *vdev = VIRTIO_DEVICE(req->dev);
>      VirtQueueElement *elem = &req->elem;
>      VirtIOBlock *blk = req->dev;
> +    BlockAIOCB *acb;
>  
>  #ifdef __linux__
>      int i;
> @@ -278,8 +279,12 @@ static int virtio_blk_handle_scsi_req(VirtIOBlockReq *req)
>      ioctl_req->hdr.sbp = elem->in_sg[elem->in_num - 3].iov_base;
>      ioctl_req->hdr.mx_sb_len = elem->in_sg[elem->in_num - 3].iov_len;
>  
> -    blk_aio_ioctl(blk->blk, SG_IO, &ioctl_req->hdr,
> -                  virtio_blk_ioctl_complete, ioctl_req);
> +    acb = blk_aio_ioctl(blk->blk, SG_IO, &ioctl_req->hdr,
> +                        virtio_blk_ioctl_complete, ioctl_req);
> +    if (!acb) {
> +        status = VIRTIO_BLK_S_UNSUPP;
> +        goto fail;
> +    }
>      return -EINPROGRESS;
>  #else
>      abort();

This leaks ioctl_req.

Kevin