Re: [offlist] Re: Crash in netlink/sk_filter_trim_cap on ARMv7 on 4.18rc1

[Russell King - ARM Linux <linux@armlinux.org.uk>]

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 : [<c0ab03b4>]    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.

-- 
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