Re: BTFIDS: FAILED unresolved symbol udp6_sock

From: Qais Yousef
Date: Tue Dec 29 2020 - 18:31:59 EST


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@xxxxxxxxxxxxxx/#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