[PATCH] xdp: fix xsk_generic_xmit errno

propagate sock_alloc_send_skb error code, not set it
to EAGAIN unconditionally, when fail to allocate skb,
which maybe causes that user space unnecessary loops

Fixes: 35fcde7f8deb "(xsk: support for Tx)"
Signed-off-by: Li RongQing <redacted>
---
 net/xdp/xsk.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c
index b6c0f08bd80d..1ba3ea262c15 100644
--- a/net/xdp/xsk.c
+++ b/net/xdp/xsk.c

@@ -353,7 +353,6 @@ static int xsk_generic_xmit(struct sock *sk)
 		len = desc.len;
 		skb = sock_alloc_send_skb(sk, len, 1, &err);
 		if (unlikely(!skb)) {
-			err = -EAGAIN;
 			goto out;
 		}
 

-- 
2.16.2

On Thu, 11 Jun 2020 at 07:11, Li RongQing [off-list ref] wrote:

propagate sock_alloc_send_skb error code, not set it
to EAGAIN unconditionally, when fail to allocate skb,
which maybe causes that user space unnecessary loops

Fixes: 35fcde7f8deb "(xsk: support for Tx)"
Signed-off-by: Li RongQing <redacted>

Thanks!
Acked-by: Björn Töpel <redacted>

Alexei/Daniel: This should go into "bpf".


Björn

On 6/11/20 10:18 AM, Björn Töpel wrote:

On Thu, 11 Jun 2020 at 07:11, Li RongQing [off-list ref] wrote:

quoted

propagate sock_alloc_send_skb error code, not set it
to EAGAIN unconditionally, when fail to allocate skb,
which maybe causes that user space unnecessary loops

Fixes: 35fcde7f8deb "(xsk: support for Tx)"
Signed-off-by: Li RongQing <redacted>

Thanks!
Acked-by: Björn Töpel <redacted>

Alexei/Daniel: This should go into "bpf".

Yep, applied, thanks!

From: Li RongQing <redacted>
Date: Thu, 11 Jun 2020 13:11:06 +0800

Since the result is a single-statement basic block you must remove the
curly braces.