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;
Date:   Tue, 29 Dec 2020 23:28:35 +0000
From:   Qais Yousef <qais.yousef@arm.com>
To:     Jiri Olsa <jolsa@redhat.com>
Cc:     Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
        Jiri Olsa <jolsa@kernel.org>, netdev@vger.kernel.org,
        bpf@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: BTFIDS: FAILED unresolved symbol udp6_sock
Message-ID: <20201229232835.cbyfmja3bu3lx7we@e107158-lin>
References: <20201229151352.6hzmjvu3qh6p2qgg@e107158-lin>
 <20201229173401.GH450923@krava>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
In-Reply-To: <20201229173401.GH450923@krava>
Precedence: bulk

Hi Jiri

On 12/29/20 18:34, Jiri Olsa wrote:
> On Tue, Dec 29, 2020 at 03:13:52PM +0000, Qais Yousef wrote:
> > Hi
> > 
> > When I enable CONFIG_DEBUG_INFO_BTF I get the following error in the BTFIDS
> > stage
> > 
> > 	FAILED unresolved symbol udp6_sock
> > 
> > I cross compile for arm64. My .config is attached.
> > 
> > I managed to reproduce the problem on v5.9 and v5.10. Plus 5.11-rc1.
> > 
> > Have you seen this before? I couldn't find a specific report about this
> > problem.
> > 
> > Let me know if you need more info.
> 
> hi,
> this looks like symptom of the gcc DWARF bug we were
> dealing with recently:
> 
>   https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97060
>   https://lore.kernel.org/lkml/CAE1WUT75gu9G62Q9uAALGN6vLX=o7vZ9uhqtVWnbUV81DgmFPw@mail.gmail.com/#r
> 
> what pahole/gcc version are you using?

I'm on gcc 9.3.0

	aarch64-linux-gnu-gcc (Ubuntu 9.3.0-17ubuntu1~20.04) 9.3.0

I was on pahole v1.17. I moved to v1.19 but I still see the same problem.

Thanks

--
Qais Yousef

> 
> we fixed pahole (v1.19) to workaround the issue and AFAIK
> there's already gcc fix as well