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Date:   Wed, 19 Jan 2022 00:33:02 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Josh Poimboeuf <jpoimboe@redhat.com>
Cc:     Nick Desaulniers <ndesaulniers@google.com>,
        Vasily Gorbik <gor@linux.ibm.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Ingo Molnar <mingo@kernel.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>,
        Luc Van Oostenryck <luc.vanoostenryck@gmail.com>,
        x86@kernel.org, llvm@lists.linux.dev, linux-sparse@vger.kernel.org,
        linux-kernel@vger.kernel.org, kernel test robot <lkp@intel.com>,
        Nathan Chancellor <nathan@kernel.org>
Subject: Re: [PATCH] objtool: prefer memory clobber & %= to volatile &
 __COUNTER__
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References: <20220114010526.1776605-1-ndesaulniers@google.com>
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On Tue, Jan 18, 2022 at 03:01:20PM -0800, Josh Poimboeuf wrote:
> With the two WARN_ONs in media_request_object_complete(), GCC apparently
> considers the two reachable() asm statements as duplicates, and it
> removes the second one.

Could that be the same thing:

net/xfrm/xfrm_output.o: warning: objtool: xfrm_output_resume()+0x2e0: unreachable instruction

I see two WARN_ONs in asm output there too...

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette