dwarves.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Hao Luo <haoluo@google.com>
To: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>,
	Andrii Nakryiko <andrii@kernel.org>,
	dwarves@vger.kernel.org, Jiri Olsa <jolsa@kernel.org>
Subject: Re: [PATCH dwarves] cmake: make libbpf's Linux UAPI headers
Date: Mon, 26 Oct 2020 14:19:51 -0700	[thread overview]
Message-ID: <CA+khW7gsJWL5yBcAqQ2mK+1Bh-toFwVipxWX14_5+ZSBL_ckgA@mail.gmail.com> (raw)
In-Reply-To: <CA+khW7j5ZJzR-zdSWApod6wRWsusuOoJqJU5UP0QZD6CcJzkZQ@mail.gmail.com>

Oops, sorry about my terrible formatting.


On Mon, Oct 26, 2020 at 2:17 PM Hao Luo <haoluo@google.com> wrote:
>
> On Mon, Oct 26, 2020 at 1:32 PM Jiri Olsa <jolsa@redhat.com> wrote:
> >
> > On Mon, Oct 26, 2020 at 04:58:30PM -0300, Arnaldo Carvalho de Melo wrote:
> > > Hi guys,
> > >
> > >       I just stumbled on this, investigating... This is with what is
> > > in the tmp branch at
> > > git://git.kernel.org/pub/scm/devel/pahole/pahole.git.
> > >
> > > error: found variable in CU '/home/acme/git/linux/security/selinux/hooks.c' that has void type
> > > Encountered error while encoding BTF.
> > >   LD      .tmp_vmlinux.kallsyms1
> > >   KSYMS   .tmp_vmlinux.kallsyms1.S
> > >   AS      .tmp_vmlinux.kallsyms1.S
> > >   LD      .tmp_vmlinux.kallsyms2
> > >   KSYMS   .tmp_vmlinux.kallsyms2.S
> > >   AS      .tmp_vmlinux.kallsyms2.S
> > >   LD      vmlinux
> > >   BTFIDS  vmlinux
> > > FAILED: load BTF from vmlinux: Unknown error -2make[1]: *** [/home/acme/git/linux/Makefile:1164: vmlinux] Error 255
> > > make[1]: Leaving directory '/home/acme/git/build/v5.10.0-rc1+'
> > > make: *** [Makefile:185: __sub-make] Error 2
> >
> > yep, I see the same and when I use --btf_encode_force,
> > it shows more of them:
> >
> > error: found variable in CU 'arch/x86/kernel/cpu/mce/core.c' that has void type
> > error: found variable in CU 'security/selinux/hooks.c' that has void type
> > error: found variable in CU 'security/selinux/hooks.c' that has void type
> > error: found variable in CU 'security/selinux/hooks.c' that has void type
> > error: found variable in CU 'security/selinux/hooks.c' that has void type
> > error: found variable in CU 'security/selinux/hooks.c' that has void type
> > error: found variable in CU 'security/selinux/hooks.c' that has void type
> > error: found variable in CU 'drivers/platform/x86/intel_pmc_core.c' that has void type
> >
> > I have no idea how variables are encoded in dwarf,
> > but I wonder it's another gcc bug ;-)
> >
> > jirka
> >
>
> Still looking. But I found if I move
>
> c815d266 (Hao Luo                  2020-08-24 17:45:23 -0700 444)
>          if (var->ip.tag.type == 0) {
> 2e719cca (Andrii Nakryiko          2020-10-08 16:39:57 -0700 445)
>                  fprintf(stderr, "error: found variable in CU '%s'
> that has void type\n",
> 2e719cca (Andrii Nakryiko          2020-10-08 16:39:57 -0700 446)
>                          cu->name);
> f3d9054b (Hao Luo                  2020-07-08 13:44:10 -0700 447)
>                  if (force)
> f3d9054b (Hao Luo                  2020-07-08 13:44:10 -0700 448)
>                          continue;
> f3d9054b (Hao Luo                  2020-07-08 13:44:10 -0700 449)
>                  err = -1;
> f3d9054b (Hao Luo                  2020-07-08 13:44:10 -0700 450)
>                  break;
> f3d9054b (Hao Luo                  2020-07-08 13:44:10 -0700 451)
>          }
> f3d9054b (Hao Luo                  2020-07-08 13:44:10 -0700 452)
>
> after
>
> 2e719cca (Andrii Nakryiko          2020-10-08 16:39:57 -0700 453)
>          type = var->ip.tag.type + type_id_off;
> 2e719cca (Andrii Nakryiko          2020-10-08 16:39:57 -0700 454)
>          linkage = var->external ? BTF_VAR_GLOBAL_ALLOCATED :
> BTF_VAR_STATIC;
> 2e719cca (Andrii Nakryiko          2020-10-08 16:39:57 -0700 455)
>          if (!percpu_var_exists(addr, &size, &name))
> 2e719cca (Andrii Nakryiko          2020-10-08 16:39:57 -0700 456)
>                  continue; /* not a per-CPU variable */
>
> the error is gone. I think we should check percpu_var_exists() before
> checking var->ip.tag.type.
>
> Hao

  reply	other threads:[~2020-10-26 21:20 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-26 19:58 [PATCH dwarves] cmake: make libbpf's Linux UAPI headers Arnaldo Carvalho de Melo
2020-10-26 20:32 ` Jiri Olsa
2020-10-26 21:17   ` Hao Luo
2020-10-26 21:19     ` Hao Luo [this message]
2020-10-26 21:39       ` Andrii Nakryiko

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=CA+khW7gsJWL5yBcAqQ2mK+1Bh-toFwVipxWX14_5+ZSBL_ckgA@mail.gmail.com \
    --to=haoluo@google.com \
    --cc=acme@kernel.org \
    --cc=andrii@kernel.org \
    --cc=dwarves@vger.kernel.org \
    --cc=jolsa@kernel.org \
    --cc=jolsa@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).