From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [offlist] Re: Crash in netlink/sk_filter_trim_cap on ARMv7 on 4.18rc1 Date: Thu, 5 Jul 2018 08:31:21 +0100 Message-ID: <20180705073120.GU17271@n2100.armlinux.org.uk> References: <7ff516fd-1d01-4d7a-1d5d-b58932c0c69d@gmail.com> <20180704234154.GT17271@n2100.armlinux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, labbott@redhat.com, linux-arm-kernel@lists.infradead.org, Daniel Borkmann , Eric Dumazet To: Peter Robinson Return-path: Received: from pandora.armlinux.org.uk ([78.32.30.218]:50690 "EHLO pandora.armlinux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752773AbeGEHba (ORCPT ); Thu, 5 Jul 2018 03:31:30 -0400 Content-Disposition: inline In-Reply-To: <20180704234154.GT17271@n2100.armlinux.org.uk> Sender: netdev-owner@vger.kernel.org List-ID: On Thu, Jul 05, 2018 at 12:41:54AM +0100, Russell King - ARM Linux wrote: > Subject says offlist, but this isn't... > > On Wed, Jul 04, 2018 at 08:33:20AM +0100, Peter Robinson wrote: > > Sorry for the delay on this from my end. I noticed there was some bpf > > bits land in the last net fixes pull request landed Monday so I built > > a kernel with the JIT reenabled. It seems it's improved in that the > > completely dead no output boot has gone but the original problem that > > arrived in the merge window still persists: > > > > [ 17.564142] note: systemd-udevd[194] exited with preempt_count 1 > > [ 17.592739] Unable to handle kernel NULL pointer dereference at > > virtual address 0000000c > > [ 17.601002] pgd = (ptrval) > > [ 17.603819] [0000000c] *pgd=00000000 > > [ 17.607487] Internal error: Oops: 805 [#10] SMP ARM > > [ 17.612396] Modules linked in: > > [ 17.615484] CPU: 0 PID: 195 Comm: systemd-udevd Tainted: G D > > 4.18.0-0.rc3.git1.1.bpf1.fc29.armv7hl #1 > > [ 17.626056] Hardware name: Generic AM33XX (Flattened Device Tree) > > [ 17.632198] PC is at sk_filter_trim_cap+0x218/0x2fc > > [ 17.637102] LR is at (null) > > [ 17.640086] pc : [] lr : [<00000000>] psr: 60000013 > > [ 17.646384] sp : cfe1dd48 ip : 00000000 fp : 00000000 > > [ 17.651635] r10: d837e000 r9 : d833be00 r8 : 00000000 > > [ 17.656887] r7 : 00000001 r6 : e003d000 r5 : 00000000 r4 : 00000000 > > [ 17.663447] r3 : 00000007 r2 : 00000000 r1 : 00000000 r0 : 00000000 > > [ 17.670009] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none > > [ 17.677180] Control: 10c5387d Table: 8fe20019 DAC: 00000051 > > [ 17.682956] Process systemd-udevd (pid: 195, stack limit = 0x(ptrval)) > > [ 17.689518] Stack: (0xcfe1dd48 to 0xcfe1e000) > > Can you provide a full disassembly of sk_filter_trim_cap from vmlinux > (iow, annotated with its linked address) for the above dump please - > alternatively a new dump with matching disassembly. Thanks. Also probably a good idea to have bpf_jit_enable set to 2 to get a dump of the bpf program being run, which I think for your problem, you'll have to hack the kernel source to do that. -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 13.8Mbps down 630kbps up According to speedtest.net: 13Mbps down 490kbps up