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Date:   Fri, 16 Jul 2021 09:07:30 +0100
From:   Mel Gorman <mgorman@techsingularity.net>
To:     Michal Such?nek <msuchanek@suse.de>
Cc:     Andrii Nakryiko <andrii.nakryiko@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Christoph Hellwig <hch@infradead.org>,
        Arnaldo Carvalho de Melo <acme@redhat.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Martin KaFai Lau <kafai@fb.com>,
        Song Liu <songliubraving@fb.com>, Yonghong Song <yhs@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Jiri Olsa <jolsa@kernel.org>,
        Hritik Vijay <hritikxx8@gmail.com>,
        Linux-BPF <bpf@vger.kernel.org>,
        Linux-Net <netdev@vger.kernel.org>,
        Linux-MM <linux-mm@kvack.org>, clm@fb.com
Subject: Re: [PATCH v3] mm/page_alloc: Require pahole v1.22 to cope with
 zero-sized struct pagesets
Message-ID: <20210716080730.GU3809@techsingularity.net>
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On Thu, Jul 15, 2021 at 09:44:53PM +0200, Michal Such?nek wrote:
> > > Well, luckily it seems we anticipated issues like that and added
> > > --skip_encoding_btf_vars argument, which I completely forgot about and
> > > just accidentally came across reviewing Arnaldo's latest pahole patch.
> > > I think that one is a much better solution, as then it will impact
> > > only those that explicitly relies on availability of BTF for per-CPU
> > > variables, which is a subset of all possible uses for kernel BTF. Sent
> > > a patch ([0]), please take a look.
> > > 
> > >   [0] https://lore.kernel.org/linux-mm/20210530002536.3193829-1-andrii@kernel.org/T/#u
> > 
> > I'm happy to have this patch used as an alternative to forcing 1.22 to
> > be the minimum version of pahole required.
> 
> Is pahole 1.22 available already?
> 

Ultimately it was of less importance because of a0b8200d06ad ("kbuild:
skip per-CPU BTF generation for pahole v1.18-v1.21"). As I write this,
pahole v1.22 has not been tagged.

-- 
Mel Gorman
SUSE Labs