On Tue, Jun 20, 2017 at 07:12:27AM -0700, Ben Greear wrote: > On 06/14/2017 03:25 PM, David Ahern wrote: > >On 6/14/17 4:23 PM, Ben Greear wrote: > >>On 06/13/2017 07:27 PM, David Ahern wrote: > >> > >>>Let's try a targeted debug patch. See attached > >> > >>I had to change it to pr_err so it would go to our serial console > >>since the system locked hard on crash, > >>and that appears to be enough to change the timing where we can no longer > >>reproduce the problem. > > > > > >ok, let's figure out which one is doing that. There are 3 debug > >statements. I suspect fib6_del_route is the one setting the state to > >FWS_U. Can you remove the debug prints in fib6_repair_tree and > >fib6_walk_continue and try again? > > We cannot reproduce with just that one printf in the kernel either. It > must change the timing too much to trigger the bug.
You might try trace_printk() which should have less impact (don't forget to enable /proc/sys/kernel/ftrace_dump_on_oops). Michal Kubecek