On Tue, Jul 09, 2013 at 07:52:31AM +0100, Jan Beulich wrote: > >>> On 08.07.13 at 17:48, Wei Liu <wei.liu2@xxxxxxxxxx> wrote: > > On Mon, Jul 08, 2013 at 03:20:26PM +0100, Jan Beulich wrote: > >> @@ -1014,7 +1025,7 @@ err: > >> > >> skb_shinfo(skb)->frags[0].page_offset = rx->offset; > >> skb_frag_size_set(&skb_shinfo(skb)->frags[0], rx->status); > >> - skb->data_len = rx->status; > >> + skb->len = skb->data_len = rx->status; > > > > This is not correct. You should not be needing this. Now you lose count > > of SKB head len. Try to go without the above line and see if it makes a > > difference? > > I don't follow - at this point, there's 0 bytes of head (this only > changes with the first call to __pskb_pull_tail()). Hence ->len == > ->data_len seems correct to me (and afaict pulling would do the > wrong thing if I dropped that change). > My bad, I suggested the wrong thing. :-( But I would prefer skb->len += skb->data_len. In the case that skb->len == 0 it's the same as your line while skb->len is not zero it would also do the right thing. As for the warning in skb_try_coalesce, I don't see any direct call to it in netfront, I will need to think about it. It looks like it's really something very deep in the stack. Wei. > Jan -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html