Re: Hang in 2.6.23-rc5

[FD Cami <francois.cami@free.fr>]

On Mon, 3 Sep 2007 04:15:01 +0530 (IST)
Satyam Sharma <satyam@infradead.org> wrote:

> On Mon, 3 Sep 2007, Alexey Dobriyan wrote:
> > 
> > Try this from net-2.6 tree:
> > 
> > --- a/net/ipv4/tcp_input.c
> > +++ b/net/ipv4/tcp_input.c
> > @@ -560,7 +560,7 @@ static u32 tcp_rto_min(struct sock *sk)
> >  	struct dst_entry *dst = __sk_dst_get(sk);
> >  	u32 rto_min = TCP_RTO_MIN;
> >  
> > -	if (dst_metric_locked(dst, RTAX_RTO_MIN))
> > +	if (dst && dst_metric_locked(dst, RTAX_RTO_MIN))
> >  		rto_min = dst->metrics[RTAX_RTO_MIN-1];
> >  	return rto_min;
> >  }
> 
> That's my impression as well. That's way too core/busy a codepath to
> have a bug in. As I said earlier, almost anybody testing -rc5 is sure
> to hit this within a few hours (probably less) -- sad, it greatly
> erodes from the usefulness of -rc5 as a release candidate.

For the record, I haven't been able to reproduce the lockup with this
patch.

Cheers

François