linux-kernel - Re: [PATCH 1/6] perf offcpu: Fix a build failure on old kernels

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: <CAM9d7ciPK4Z05LYNNukAsTdEMEce4hOWRa83THbENDuWjXcyEQ@mail.gmail.com>
Date:   Tue, 28 Jun 2022 09:52:28 -0700
From:   Namhyung Kim <namhyung@...nel.org>
To:     Arnaldo Carvalho de Melo <acme@...nel.org>
Cc:     Jiri Olsa <jolsa@...nel.org>, Ingo Molnar <mingo@...nel.org>,
        Peter Zijlstra <peterz@...radead.org>,
        LKML <linux-kernel@...r.kernel.org>,
        Ian Rogers <irogers@...gle.com>,
        linux-perf-users <linux-perf-users@...r.kernel.org>,
        Song Liu <songliubraving@...com>, Hao Luo <haoluo@...gle.com>,
        Milian Wolff <milian.wolff@...b.com>,
        bpf <bpf@...r.kernel.org>, Blake Jones <blakejones@...gle.com>
Subject: Re: [PATCH 1/6] perf offcpu: Fix a build failure on old kernels

On Tue, Jun 28, 2022 at 7:44 AM Arnaldo Carvalho de Melo
<acme@...nel.org> wrote:
>
> Em Fri, Jun 24, 2022 at 04:13:08PM -0700, Namhyung Kim escreveu:
> > Old kernels have task_struct which contains "state" field and newer
> > kernels have "__state".  While the get_task_state() in the BPF code
> > handles that in some way, it assumed the current kernel has the new
> > definition and it caused a build error on old kernels.
> >
> > We should not assume anything and access them carefully.  Do not use
> > the task struct directly and access them using new and old definitions
> > in a row.
>
> I added a:
>
> Fixes: edc41a1099c2d08c ("perf record: Enable off-cpu analysis with BPF")
>
> Ok?

Sure, thanks for doing this!
Namhyung