linux-kernel - Re: [PATCH 1/1] perf build: Require at least clang 16.0.6 to build BPF skeletons

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <caad2d84-a8ff-4304-b8ab-04642ea18323@linaro.org>
Date: Thu, 12 Sep 2024 15:40:32 +0100
From: James Clark <james.clark@...aro.org>
To: Arnaldo Carvalho de Melo <acme@...nel.org>,
 Howard Chu <howardchu95@...il.com>
Cc: Ian Rogers <irogers@...gle.com>, Adrian Hunter <adrian.hunter@...el.com>,
 Alan Maguire <alan.maguire@...cle.com>, Jiri Olsa <jolsa@...nel.org>,
 Kan Liang <kan.liang@...ux.intel.com>, Namhyung Kim <namhyung@...nel.org>,
 Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
 linux-perf-users@...r.kernel.org
Subject: Re: [PATCH 1/1] perf build: Require at least clang 16.0.6 to build
 BPF skeletons



On 11/09/2024 13:24, Arnaldo Carvalho de Melo wrote:
> Howard reported problems using perf features that use BPF:
> 
>    perf $ clang -v
>    Debian clang version 15.0.6
>    Target: x86_64-pc-linux-gnu
>    Thread model: posix
>    InstalledDir: /bin
>    Found candidate GCC installation: /bin/../lib/gcc/x86_64-linux-gnu/12
>    Selected GCC installation: /bin/../lib/gcc/x86_64-linux-gnu/12
>    Candidate multilib: .;@m64
>    Selected multilib: .;@m64
>    perf $ ./perf trace -e write --max-events=1
>    libbpf: prog 'sys_enter_rename': BPF program load failed: Permission denied
>    libbpf: prog 'sys_enter_rename': -- BEGIN PROG LOAD LOG --
>    0: R1=ctx() R10=fp0
> 
> But it works with:
> 
>    perf $ clang -v
>    Debian clang version 16.0.6 (15~deb12u1)
>    Target: x86_64-pc-linux-gnu
>    Thread model: posix
>    InstalledDir: /bin
>    Found candidate GCC installation: /bin/../lib/gcc/x86_64-linux-gnu/12
>    Selected GCC installation: /bin/../lib/gcc/x86_64-linux-gnu/12
>    Candidate multilib: .;@m64
>    Selected multilib: .;@m64
>    perf $ ./perf trace -e write --max-events=1
>         0.000 ( 0.009 ms): gmain/1448 write(fd: 4, buf: \1\0\0\0\0\0\0\0, count: 8)                         = 8 (kworker/0:0-eve)
>    perf $
> 
> So lets make that the required version, if you happen to have a slightly
> older version where this work, please report so that we can adjust the
> minimum required version.
> 

I wasn't able to reproduce the issue with either of these versions. But 
I suppose it could be an issue with only 15.0.6.

$ clang -v
Ubuntu clang version 15.0.7
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/bin
Found candidate GCC installation: /usr/bin/../lib/gcc/x86_64-linux-gnu/11
Found candidate GCC installation: /usr/bin/../lib/gcc/x86_64-linux-gnu/12
Selected GCC installation: /usr/bin/../lib/gcc/x86_64-linux-gnu/12
Candidate multilib: .;@m64
Selected multilib: .;@m64


Ubuntu clang version 14.0.0-1ubuntu1.1
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/bin
Found candidate GCC installation: /usr/bin/../lib/gcc/x86_64-linux-gnu/11
Found candidate GCC installation: /usr/bin/../lib/gcc/x86_64-linux-gnu/12
Selected GCC installation: /usr/bin/../lib/gcc/x86_64-linux-gnu/12
Candidate multilib: .;@m64
Selected multilib: .;@m64