Subject: BPF crash with 3.18-rc1 on arm64 Juno hardware

From: [email-masked] (Andre Przywara)
Date: Fri, 24 Oct 2014 11:34:51 +0100

Hi,

On 24/10/14 11:31, Catalin Marinas wrote:
> On Thu, Oct 23, 2014 at 06:23:49PM +0100, Z Lim wrote:
>> On Thu, Oct 23, 2014 at 10:00 AM, Andre Przywara <[email-masked]> wrote:
>>> I see a crash with 3.18-rc1 on a Juno board related to bpf_jit (see dump
>>> below). Userland tries to carry on afterwards, but eventually hangs in
>>> RCU stalls.
>>> The kernel has just CONFIG_BPF_JIT enabled, I guess Ubuntu enables this
>>> automatically if detected.
>>
>> When net-next and arm64-next merged in mainline, a silent failure is
>> introduced due to new enhancements in net/bpf.
>> This was actually uncovered before 3.18 merge window, and Daniel's
>> patch to fix this was discussed here [1].
>> I see that Catalin has queued up this patch in fixes/core [2].
>
> Indeed. Pull request to Linus will go out later today.

Indeed this patch fixes it for me.
Thanks to both of you!

Cheers,
Andre.

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