On Mon, Jul 11, 2016 at 12:45 PM, <nuclear...@nuclearcat.com> wrote: > Hi > > On latest kernel i noticed kernel panic happening 1-2 times per day. It is > also happening on older kernel (at least 4.5.3). > ... > [42916.426463] Call Trace: > [42916.426658] <IRQ> > > [42916.426719] [<ffffffff81843786>] skb_push+0x36/0x37 > [42916.427111] [<ffffffffa00e8ce5>] ppp_start_xmit+0x10f/0x150 > [ppp_generic] > [42916.427314] [<ffffffff81853467>] dev_hard_start_xmit+0x25a/0x2d3 > [42916.427516] [<ffffffff818530f2>] ? > validate_xmit_skb.isra.107.part.108+0x11d/0x238 > [42916.427858] [<ffffffff8186dee3>] sch_direct_xmit+0x89/0x1b5 > [42916.428060] [<ffffffff8186e142>] __qdisc_run+0x133/0x170 > [42916.428261] [<ffffffff81850034>] net_tx_action+0xe3/0x148 > [42916.428462] [<ffffffff810c401a>] __do_softirq+0xb9/0x1a9 > [42916.428663] [<ffffffff810c4251>] irq_exit+0x37/0x7c > [42916.428862] [<ffffffff8102b8f7>] smp_apic_timer_interrupt+0x3d/0x48 > [42916.429063] [<ffffffff818cb15c>] apic_timer_interrupt+0x7c/0x90
Interesting, we call a skb_cow_head() before skb_push() in ppp_start_xmit(), I have no idea why this could happen. Do you have any tc qdisc, filter or actions on this ppp device?
