Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <CAFDeuWM7D-Upi84-JovKa3g8Y_4fjv65jND3--e9u-tER3WmVA@mail.gmail.com>
 <82b757bb-1f49-ab02-2f4b-89577d56fec9@kernel.org> <20201020122015.GH2294271@kernel.org>
 <f7246cb6-901e-0bc3-eb18-194d1754da53@kernel.org> <20201021112900.GN2342001@kernel.org>
In-Reply-To: <20201021112900.GN2342001@kernel.org>
From:   Andrii Nakryiko <andrii.nakryiko@gmail.com>
Date:   Wed, 21 Oct 2020 08:53:16 -0700
Message-ID: <CAEf4BzbpRaDsRGv+V5xvhHERJA7zoXwOnL_WJCimHHLk=tM3nw@mail.gmail.com>
Subject: Re: Segfault in pahole 1.18 when building kernel 5.9.1 for arm64
To:     Arnaldo Carvalho de Melo <acme@kernel.org>
Cc:     Jiri Slaby <jirislaby@kernel.org>,
        =?UTF-8?B?w4lyaWNvIFJvbGlt?= <erico.erc@gmail.com>,
        dwarves@vger.kernel.org, open list <linux-kernel@vger.kernel.org>,
        Arnaldo Carvalho de Melo <acme@redhat.com>,
        Hao Luo <haoluo@google.com>, Andrii Nakryiko <andriin@fb.com>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Wed, Oct 21, 2020 at 6:48 AM Arnaldo Carvalho de Melo
<acme@kernel.org> wrote:
>
> Em Wed, Oct 21, 2020 at 08:22:40AM +0200, Jiri Slaby escreveu:
> > On 20. 10. 20, 14:20, Arnaldo Carvalho de Melo wrote:
> > > > Yeah, I observe the very same. I reported it at:
> > > > https://bugzilla.suse.com/show_bug.cgi?id=1177921
>
> > > Would it be possible to try with
> > > https://git.kernel.org/pub/scm/devel/pahole/pahole.git/commit/?h=tmp.libbtf_encoder
> > > ?
>
> > Yes, that branch fixes the crashes and the kernel build finishes. The
> > zero-sized symbol error remains.
>
> > So what should distributions do now -- should we switch to a pahole snapshot
> > for a while?
>
> That would do the trick, I just completed my testing and pushed to the
> master branch on kernel.org and github, tests detailed at:
>
> https://git.kernel.org/pub/scm/devel/pahole/pahole.git/commit/?id=040fd7f585c9b9fcf4475d294b3f5ddf78405297
>
> There are some minor bug reports I want to address but my ETA right now
> is the end of this week to release v1.19.

I've just sent a patch that skips zero-sized ELF symbols without a
warning or error.

>
> - Arnaldo