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Date:   Mon, 16 Jan 2023 23:05:15 -0800
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Subject: Re: [PATCH] tools: bpf: Disable stack protector
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To:     Peter Foley <pefoley2@pefoley.com>,
        Eduard Zingerman <eddyz87@gmail.com>
Cc:     Quentin Monnet <quentin@isovalent.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
        Martin KaFai Lau <martin.lau@linux.dev>,
        Song Liu <song@kernel.org>, Yonghong Song <yhs@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@kernel.org>,
        Stanislav Fomichev <sdf@google.com>,
        Hao Luo <haoluo@google.com>, Jiri Olsa <jolsa@kernel.org>,
        Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Tom Rix <trix@redhat.com>, bpf@vger.kernel.org,
        linux-kernel@vger.kernel.org, llvm@lists.linux.dev,
        "Jose E. Marchesi" <jose.marchesi@oracle.com>
References: <20230114-bpf-v1-1-f836695a8b62@pefoley.com>
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From:   Yonghong Song <yhs@meta.com>
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On 1/16/23 2:49 PM, Peter Foley wrote:
> On Mon, Jan 16, 2023 at 4:59 AM Eduard Zingerman <eddyz87@gmail.com> wrote:
>>
>> A bit tangential, but since BPF LLVM backend does not support the
>> stack protector (should it?) there is also an option to adjust LLVM
>> to avoid this instrumentation, WDYT?
>>
> 
> That would probably be worth doing, yes.
> But given that won't help already released versions of clang, it
> should probably happen in addition to this patch.

Peter,

If I understand correctly (by inspecting clang code), the stack 
protector is off by default. Do you have link to Gentoo build
page to show how they enable stack protector? cmake config or
a private patch?

Jose,

How gcc-bpf handle stack protector? The compiler just disables
stack protector for bpf target?