Message-ID: <7189da9a-f634-01ae-194d-a4d14a319a1c@intel.com>
Date:   Wed, 22 Feb 2023 07:33:34 -0800
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Subject: Re: [PATCH] bpf: Fix undeclared function 'barrier_nospec' warning
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To:     Geert Uytterhoeven <geert@linux-m68k.org>,
        Viresh Kumar <viresh.kumar@linaro.org>
Cc:     Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        John Fastabend <john.fastabend@gmail.com>,
        Andrii Nakryiko <andrii@kernel.org>,
        Martin KaFai Lau <martin.lau@linux.dev>,
        Song Liu <song@kernel.org>, Yonghong Song <yhs@fb.com>,
        KP Singh <kpsingh@kernel.org>,
        Stanislav Fomichev <sdf@google.com>,
        Hao Luo <haoluo@google.com>, Jiri Olsa <jolsa@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        bpf@vger.kernel.org, linux-kernel@vger.kernel.org
References: <9c476aa64c9588205817833dbaa622f87c0e0081.1677051600.git.viresh.kumar@linaro.org>
 <CAMuHMdXd3876o+petD51xfnJRBOOg=oqkO_pdsmcr8=Uec2KDg@mail.gmail.com>
From:   Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <CAMuHMdXd3876o+petD51xfnJRBOOg=oqkO_pdsmcr8=Uec2KDg@mail.gmail.com>
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On 2/22/23 07:03, Geert Uytterhoeven wrote:
> On Wed, Feb 22, 2023 at 9:26 AM Viresh Kumar <viresh.kumar@linaro.org> wrote:
>> Add the missing header for architectures that don't define
>> the barrier_nospec() macro. The nospec.h header is added after the
>> inclusion of barrier.h to avoid redefining the macro for architectures
>> that already define barrier_nospec() in their respective barrier.h
>> headers.
>>
>> Fixes: 74e19ef0ff80 ("uaccess: Add speculation barrier to copy_from_user()")
>> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
>> ---
>> Linus's master branch fails currently to build for arm64 without this commit.
> Not just arm64 ????
> http://kisskb.ellerman.id.au/kisskb/head/5b7c4cabbb65f5c469464da6c5f614cbd7f730f2

Thanks for the fix, and sorry for the breakage, folks!  Obviously:

Tested-by: Dave Hansen <dave.hansen@linux.intel.com>

Now time to go make sure I have bpf turned on in all my cross builds.