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From:   Thomas Gleixner <tglx@linutronix.de>
To:     Yu-cheng Yu <yu-cheng.yu@intel.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@redhat.com>,
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Cc:     Yu-cheng Yu <yu-cheng.yu@intel.com>
Subject: Re: [RFC PATCH 4/5] selftest/x86: Fix sysret_rip with ENDBR
In-Reply-To: <20200521211720.20236-5-yu-cheng.yu@intel.com>
References: <20200521211720.20236-1-yu-cheng.yu@intel.com> <20200521211720.20236-5-yu-cheng.yu@intel.com>
Date:   Thu, 21 May 2020 23:34:27 +0200
Message-ID: <878shlt1jw.fsf@nanos.tec.linutronix.de>
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Yu-cheng Yu <yu-cheng.yu@intel.com> writes:

> Insert endbr64 to assembly code of sysret_rip.

This changelog explains what the patch does, but not the WHY. It also
lacks any information why this is harmless for !CET enabled systems.

> Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
> ---

Please consult Dave Hansen about the void between your Signed-off-by
and the '---' line.

Thanks,

        tglx