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From:   Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= <toke@redhat.com>
To:     Sami Tolvanen <samitolvanen@google.com>
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        Jesper Dangaard Brouer <brouer@redhat.com>
Subject: Re: [PATCH] bpf: validate bpf_func when BPF_JIT is enabled
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Date:   Fri, 13 Sep 2019 14:19:26 +0200
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Sami Tolvanen <samitolvanen@google.com> writes:

> On Thu, Sep 12, 2019 at 3:52 AM Toke Høiland-Jørgensen <toke@redhat.com> wrote:
>> I think it would be good if you do both. I'm a bit worried that XDP
>> performance will end up in a "death by a thousand paper cuts" situation,
>> so I'd rather push back on even relatively small overheads like this; so
>> being able to turn it off in the config would be good.
>
> OK, thanks for the feedback. In that case, I think it's probably
> better to wait until we have CFI ready for upstreaming and use the
> same config for this one.

SGTM, thanks!

>> Can you share more details about what the "future CFI checking" is
>> likely to look like?
>
> Sure, I posted an overview of CFI and what we're doing in Pixel devices here:
>
> https://android-developers.googleblog.com/2018/10/control-flow-integrity-in-android-kernel.html

Great, thank you.

-Toke