On Wed, 13 Feb 2008 00:48:29 -0800 Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote: > On Tue, 12 Feb 2008 22:46:01 +1100 Ben Nizette <bn@xxxxxxxxxxxxxxx> wrote: > > > > > On an AVR32, root over NFS, config attached, running (from a startup > > script): > > > > iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE > > > > Results in (dmesg extract including a bit of context for good measure): > > -------------8<---------------- > > VFS: Mounted root (nfs filesystem). > > Freeing init memory: 72K (90000000 - 90012000) > > eth0: no IPv6 routers present > > warning: `dnsmasq' uses 32-bit capabilities (legacy support in use) Hmm. What does that mean? What size do capabilities normally have? > > ip_tables: (C) 2000-2006 Netfilter Core Team > > nf_conntrack version 0.5.0 (1024 buckets, 4096 max) > > Unable to handle kernel paging request at virtual address d76a7138 > > ptbr = 91d3b000 pgd = 0000e5f3 pte = 00014370 Hmm. It actually found something in the pte? Looks like a swap entry...but that doesn't make sense at that virtual address. Userspace is below 0x80000000. > > Oops: Kernel access of bad area, sig: 11 [#1] > > FRAME_POINTER chip: 0x01f:0x1e82 rev 2 > > Modules linked in: nf_conntrack_ipv4(+) nf_conntrack ip_tables > > PC is at kmem_cache_alloc+0x2c/0x54 > > LR is at nf_conntrack_l4proto_register+0x34/0x9c [nf_conntrack] > > I take it that the above means that the crash is in kmem_cache_alloc()? That's correct. > If so, the bug could be almost anywhere - in slab, or in some random piece > of code which scribbles on slab's data structures. Yes, it looks like memory corruption, especially since the page table appears to be corrupted as well. But I'll have a look and see if the code that dumps the pte is doing something bogus... > > Perfectly repeatable. > > If my theory is correct, changing pretty much anything in the kernel config > might just make it go away. But still, it would be most valuable if you > could try running a bisection search, as described in > http://www.kernel.org/doc/local/git-quick.html, thanks. Yes, that would be very valuable. Haavard - To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
