On Sat, 12 Feb 2022 12:03:49 +0100 Lorenzo Bianconi wrote:
> On Feb 11, Jakub Kicinski wrote:
> > On Fri, 11 Feb 2022 02:20:31 +0100 Lorenzo Bianconi wrote:
> > > + if (skb_shared(skb) || skb_head_is_locked(skb)) {
> >
> > Is this sufficient to guarantee that the frags can be written?
> > skb_cow_data() tells a different story.
>
> Do you mean to consider paged part of the skb always not writable, right?
> In other words, we should check something like:
>
> if (skb_shared(skb) || skb_head_is_locked(skb) ||
> skb_shinfo(skb)->nr_frags) {
> ...
> }
Yes, we do have skb_has_shared_frag() but IDK if it guarantees frags
are writable :S
