Mon, Oct 23, 2017 at 06:42:50PM +0000, Levin, Alexander (Sasha Levin) wrote:
> On Mon, Oct 23, 2017 at 11:39:22AM -0400, Tim Hansen wrote:
> >Mark hlist nodes in sk rcu iterator as protected by the rcu.
> >hlist_next_rcu accomplishes this and silences the warnings
> >sparse throws for net/ipv4/udp.c and net/ipv6/udp.c.
> >
> >Found with make C=1 net/ipv4/udp.o on linux-next tag
> >next-20171009.
> >
> >Signed-off-by: Tim Hansen <devtimhan...@gmail.com>
> >---
> > include/net/sock.h | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
> >
> >diff --git a/include/net/sock.h b/include/net/sock.h
> >index 64e5ac41b9cf..96cb7b7e4924 100644
> >--- a/include/net/sock.h
> >+++ b/include/net/sock.h
> >@@ -737,10 +737,10 @@ static inline void sk_add_bind_node(struct sock *sk,
> > *
> > */
> > #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset)
> > \
> >- for (pos = rcu_dereference((head)->first); \
> >+ for (pos = rcu_dereference(hlist_next_rcu((head)->first)); \
>
> See below.
>
> > pos != NULL && \
> > ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \
> >- pos = rcu_dereference(pos->next))
> >+ pos = rcu_dereference(hlist_next_rcu(pos->next)))
>
> This will return the next-next node instead of just the next one. You
> probably want just hlist_next_rcu(pos) here.
>
> --
>
> Thanks,
> Sasha
Thanks Sasha, dumb oversight on my part. Sent in v3 of this patch.
