Unfortunately, the patch didn't help -- I've got the same stacktrace with slightly different offset (+3) within the function.
Now trying to get full stacktrace via netconsole. Need more time. Meanwhile, any other ideas on what went wrong? On December 22, 2015 4:10:32 AM EET, Yuchung Cheng <ych...@google.com> wrote: >On Mon, Dec 21, 2015 at 12:25 PM, Oleksandr Natalenko ><oleksa...@natalenko.name> wrote: >> Commit 3759824da87b30ce7a35b4873b62b0ba38905ef5 (tcp: PRR uses CRB >mode by >> default and SS mode conditionally) introduced changes to >net/ipv4/tcp_input.c >> tcp_cwnd_reduction() that, possibly, cause division by zero, and >therefore, >> kernel panic in interrupt handler [1]. >> >> Reverting 3759824da87b30ce7a35b4873b62b0ba38905ef5 seems to fix the >issue. >> >> I'm able to reproduce the issue on 4.3.0–4.3.3 once per several day >> (occasionally). >> >> What could be done to help in debugging this issue? >Do you have ECN enabled (i.e. sysctl net.ipv4.tcp_ecn > 0)? > >If so I suspect an ACK carrying ECE during CA_Loss causes entering CWR >state w/o calling tcp_init_cwnd_reduct() to set tp->prior_cwnd. Can >you try this debug / quick-fix patch and send me the error message if >any? > > >> >> Regards, >> Oleksandr. >> >> [1] http://i.piccy.info/ >> >i9/6f5cb187c4ff282d189f78c63f95af43/1450729403/283985/951663/panic.jpg -- Sent from my Android device with K-9 Mail. Please excuse my brevity. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
