Re: [RFC PATCH net-next 2/6] x86: bpf_jit_comp: supportBPF_S_ANC_SECCOMP_LD_W instruction

[Xi Wang]

On Fri, Apr 26, 2013 at 11:11 AM, Eric Dumazet <eric.dumazet@xxxxxxxxx> wrote:
> 2) Calling a function potentially destroys some registers.
>    %rdi,%r8,%r9 for instance, so we are going to crash very easily.
>
> I dont know, I feel a bit uncomfortable having to explain this to
> someone sending security related patches...

My old code did save these registers.  But, do we really need that for
seccomp?  For example, %rdi (skb) is always NULL and never used by
seccomp filters.  Did I miss anything?

- xi
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