Hello, Jan!
On 2/23/21 6:26 PM, Jan Beulich wrote:
> In order for subsequent unmapping to not mistakenly unmap handle 0,
> record a perceived always-invalid one instead.
>
> Signed-off-by: Jan Beulich <jbeul...@suse.com>
> Reviewed-by: Juergen Gross <jgr...@suse.com>
Reviewed-by: Oleksandr Andrushchenko <oleksandr_andrushche...@epam.com>
> ---
> v2: Use INVALID_GRANT_HANDLE.
>
> --- a/drivers/xen/xen-front-pgdir-shbuf.c
> +++ b/drivers/xen/xen-front-pgdir-shbuf.c
> @@ -305,11 +305,18 @@ static int backend_map(struct xen_front_
>
> /* Save handles even if error, so we can unmap. */
> for (cur_page = 0; cur_page < buf->num_pages; cur_page++) {
> - buf->backend_map_handles[cur_page] = map_ops[cur_page].handle;
> - if (unlikely(map_ops[cur_page].status != GNTST_okay))
> + if (likely(map_ops[cur_page].status == GNTST_okay)) {
> + buf->backend_map_handles[cur_page] =
> + map_ops[cur_page].handle;
> + } else {
> + buf->backend_map_handles[cur_page] =
> + INVALID_GRANT_HANDLE;
> + if (!ret)
> + ret = -ENXIO;
> dev_err(&buf->xb_dev->dev,
> "Failed to map page %d: %d\n",
> cur_page, map_ops[cur_page].status);
> + }
> }
>
> if (ret) {
