Date:   Fri, 7 Jan 2022 20:52:59 +0900
From:   Masami Hiramatsu <mhiramat@kernel.org>
To:     Nathan Chancellor <nathan@kernel.org>
Cc:     Samuel Zeter <samuelzeter@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>,
        Nick Desaulniers <ndesaulniers@google.com>,
        linux-kernel@vger.kernel.org, llvm@lists.linux.dev,
        Masami Hiramatsu <mhiramat@kernel.org>
Subject: Re: [PATCH 0/2] *** Fix reformat_objdump.awk ***
Message-Id: <20220107205259.e66ff1bd90ac218611bf1178@kernel.org>
In-Reply-To: <Ydc8wUjX4hnHg7ZE@archlinux-ax161>
References: <20220106023606.283953-1-samuelzeter@gmail.com>
        <Ydc8wUjX4hnHg7ZE@archlinux-ax161>
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Hi Samuel and Nathan,

Thanks for working on this issue. I didn't noticed that the llvm has
this difference. Anyway both patches look good to me.

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>

for this series.

And if you resend it, please add "x86@kernel.org" to Cc.

Thank you!

On Thu, 6 Jan 2022 12:02:25 -0700
Nathan Chancellor <nathan@kernel.org> wrote:

> On Thu, Jan 06, 2022 at 01:36:03PM +1100, Samuel Zeter wrote:
> > These are two small patches which originally dealt with
> > the problem found at:
> > 
> > https://github.com/ClangBuiltLinux/linux/issues/1364
> > 
> > The original steps to reproduce were:
> > $ make -skj"$(nproc)" LLVM=1 LLVM_IAS=1 defconfig
> > $ scripts/config -e X86_DECODER_SELFTEST
> > $ make -skj"$(nproc)" LLVM=1 LLVM_IAS=1 olddefconfig bzImage
> > 
> > Which resulted in the error:
> > arch/x86/tools/insn_decoder_test: warning: objdump says 0 bytes, but
> > insn_get_length() says 2
> > 
> > Upon inspection it turned out llvm-objdump was formatting its
> > output differently, which caused objdump_reformat.awk to incorrectly
> > output its values.
> > 
> > After fixing that bug, a second one was seen where the instruction
> > "wait" was incorrectly matched with "fwait", which again caused
> > insn_decoder_test to fail.
> 
> Thanks a lot for sending these fixes!
> 
> I can confirm with this series and the removal of chkobjdump.awk [1] on
> top of v5.16-rc8, the insn_decoder_test now passes with LLVM 11 through
> 14.
> 
> Tested-by: Nathan Chancellor <nathan@kernel.org>
> 
> For the future, I recommend putting the maintainers in the "To" field,
> rather than "Cc", to ensure they actually see it. Additionally, I see
> some small nits in the commit message that the tip maintainers might
> comment on, see
> 
> https://www.kernel.org/doc/html/latest/process/maintainer-tip.html#changelog
> 
> for some more info.
> 
> Masami Hiramatsu originally wrote this file and has a few fixes to it
> since, adding him now for review. The original thread is available at:
> 
> https://lore.kernel.org/r/20220106023606.283953-1-samuelzeter@gmail.com/
> 
> [1]: https://git.kernel.org/nathan/c/2f137c324b21f1c21b8830d8896cb9957009f969
> 
> Cheers,
> Nathan


-- 
Masami Hiramatsu <mhiramat@kernel.org>