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Subject: Re: [PATCH v7 net-next 1/3] filter: add Extended BPF interpreter
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From: Eric Dumazet <eric.dumazet@gmail.com>
To: Alexei Starovoitov <ast@plumgrid.com>
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On Sun, 2014-03-09 at 11:57 -0700, Alexei Starovoitov wrote:

> In sk_run_filter_ext() I used "u64 stack[64];", but "u64 stack[60];" is
> safe too, but I didn't want to go into extensive explanation
> of 'magic' 60 number in the first patch, so I just rounded it to 64.
> Since now you understand, I can make it stack[60] now :)

My point was : You should not use 64 or 60 in the C code.

I should not have to ask you why it is safe.

It should be obvious just reading the source code. And so far it is not.

Thats why we use macros and comments at the macro definition.