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Date:   Fri, 12 Feb 2021 12:45:47 -0500
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Josh Poimboeuf <jpoimboe@redhat.com>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Xi Ruoyao <xry111@mengyan1223.wang>,
        "# 3.4.x" <stable@vger.kernel.org>,
        Arnd Bergmann <arnd@kernel.org>,
        "Peter Zijlstra (Intel)" <peterz@infradead.org>,
        Miroslav Benes <mbenes@suse.cz>,
        "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" <x86@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        linux-tip-commits@vger.kernel.org
Subject: Re: [tip: objtool/urgent] objtool: Fix seg fault with Clang
 non-section symbols
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On Fri, 12 Feb 2021 11:07:50 -0600
Josh Poimboeuf <jpoimboe@redhat.com> wrote:


> > Any ideas are appreciated.  
> 
> [ Adding Steve Rostedt ]
> 
> This error message comes from recordmcount.  It probably can't handle
> the missing STT_SECTION symbols which are getting stripped by the new
> binutils.  (Objtool also had trouble with that.)
> 
> No idea why you only see this on 4.4 though.
> 

Just taking a quick look, but would something like this work?

I created this against v4.4.257.

-- Steve

diff --git a/scripts/recordmcount.h b/scripts/recordmcount.h
index 04151ede8043..698404f092d0 100644
--- a/scripts/recordmcount.h
+++ b/scripts/recordmcount.h
@@ -437,6 +437,8 @@ static unsigned find_secsym_ndx(unsigned const txtndx,
 			if (w2(ehdr->e_machine) == EM_ARM
 			    && ELF_ST_TYPE(symp->st_info) == STT_FUNC)
 				continue;
+			if (ELF_ST_TYPE(symp->st_info) == STT_SECTION)
+				continue;
 
 			*recvalp = _w(symp->st_value);
 			return symp - sym0;