On Sun, Jan 30, 2005 at 06:58:27PM +0100, Patrick McHardy wrote: > Patrick McHardy wrote: > >> Russell King wrote: > >>> I don't know if the code is using fragment lists in ip_fragment(), but > >>> on reading the code a question comes to mind: if we have a list of > >>> fragments, does each fragment skb have a valid (and refcounted) dst > >>> pointer before ip_fragment() does it's job? If yes, then isn't the > >>> first ip_copy_metadata() in ip_fragment() going to overwrite this > >>> pointer without dropping the refcount? > >>> > >> Nice spotting. If conntrack isn't loaded defragmentation happens after > >> routing, so this is likely the cause. > > > > OTOH, if conntrack isn't loaded forwarded packet are never defragmented, > > so frag_list should be empty. So probably false alarm, sorry. > > Ok, final decision: you are right :) conntrack also defragments locally > generated packets before they hit ip_fragment. In this case the fragments > have skb->dst set.
Good news - with this in place, I no longer have refcounts of 14000! After 18 minutes (the first clearout of the dst cache from 500 odd down to 11 or so), all dst cache entries have a ref count of zero. I'll check it again later this evening to be sure. Thanks Patrick. > ===== net/ipv4/ip_output.c 1.74 vs edited ===== > --- 1.74/net/ipv4/ip_output.c 2005-01-25 01:40:10 +01:00 > +++ edited/net/ipv4/ip_output.c 2005-01-30 18:54:43 +01:00 > @@ -389,6 +389,7 @@ > to->priority = from->priority; > to->protocol = from->protocol; > to->security = from->security; > + dst_release(to->dst); > to->dst = dst_clone(from->dst); > to->dev = from->dev; > -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: 2.6 PCMCIA - http://pcmcia.arm.linux.org.uk/ 2.6 Serial core - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
