linux-kernel - Re: next: zip.c:35:8: error: packed attribute causes inefficient alignment for 'magic' [-Werror=attributes]

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] [day] [month] [year] [list]

Message-ID: <20230315151742.ydv7dw6agaeqxcj5@nuc>
Date:   Wed, 15 Mar 2023 15:17:42 +0000
From:   Daniel Müller <deso@...teo.net>
To:     Andrii Nakryiko <andrii.nakryiko@...il.com>
Cc:     Ian Rogers <irogers@...gle.com>,
        Naresh Kamboju <naresh.kamboju@...aro.org>,
        Jiri Olsa <jolsa@...nel.org>,
        Arnaldo Carvalho de Melo <acme@...nel.org>,
        Namhyung Kim <namhyung@...nel.org>,
        open list <linux-kernel@...r.kernel.org>,
        bpf <bpf@...r.kernel.org>, lkft-triage@...ts.linaro.org,
        Linux-Next Mailing List <linux-next@...r.kernel.org>,
        Andrii Nakryiko <andrii@...nel.org>,
        Alexei Starovoitov <ast@...nel.org>,
        Daniel Borkmann <daniel@...earbox.net>,
        Song Liu <song@...nel.org>, Yonghong Song <yhs@...com>,
        KP Singh <kpsingh@...nel.org>,
        Anders Roxell <anders.roxell@...aro.org>
Subject: Re: next: zip.c:35:8: error: packed attribute causes inefficient
 alignment for 'magic' [-Werror=attributes]

On Tue, Mar 14, 2023 at 04:56:15PM -0700, Andrii Nakryiko wrote:
> On Tue, Mar 14, 2023 at 1:01 PM Ian Rogers <irogers@...gle.com> wrote:
> >
> > On Tue, Mar 14, 2023 at 11:52 AM Andrii Nakryiko
> > <andrii.nakryiko@...il.com> wrote:
> > >
> > > On Mon, Mar 13, 2023 at 11:38 PM Naresh Kamboju
> > > <naresh.kamboju@...aro.org> wrote:
> > > >
> > > > perf builds failing from Linux next-20230307..next-20230314 but pass on
> > > > Linux mainline v6.3-rc2.
> > > >
> > > > Reported-by: Linux Kernel Functional Testing <lkft@...aro.org>
> > >
> > > Thanks for the report, but I'm not sure what's wrong here. We added
> > > __attribute__((packed)) attribute intentionally and want to keep it
> > > this way. It seems like perf itself is using packed structs (e.g.,
> > > struct debug_line_header in util/genelf_debug.c), so I'm wondering why
> > > that code doesn't cause any problems.
> > >
> > > Any hints from perf folks?
> >
> > We use a #pragma to disable the warnings in at least one place:
> > https://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git/tree/tools/lib/perf/include/perf/event.h?h=perf-tools#n194
> >
> 
> Ok, let's do the same here. Daniel, can you please send a follow up
> patch to silence this warning?

Sounds good.

Thanks,
Daniel