[PATCH net v2] xsk: Return error code if force_zc is set

[Zhang Changzhong]

If force_zc is set, we should exit out with an error, not fall back to
copy mode.

Fixes: 921b68692abb ("xsk: Enable sharing of dma mappings")
Reported-by: Hulk Robot <hul...@huawei.com>
Signed-off-by: Zhang Changzhong <zhangchangzh...@huawei.com>
---
 net/xdp/xsk_buff_pool.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/xdp/xsk_buff_pool.c b/net/xdp/xsk_buff_pool.c
index 9287edd..d5adeee 100644
--- a/net/xdp/xsk_buff_pool.c
+++ b/net/xdp/xsk_buff_pool.c
@@ -175,6 +175,7 @@ static int __xp_assign_dev(struct xsk_buff_pool *pool,
 
        if (!pool->dma_pages) {
                WARN(1, "Driver did not DMA map zero-copy buffers");
+               err = -EINVAL;
                goto err_unreg_xsk;
        }
        pool->umem->zc = true;
-- 
2.9.5