Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Subject: Re: [PATCH] x86: perf: insn: Tweak opcode map for Intel CET
 instructions
To:     Mingbo Zhang <whensungoes@gmail.com>, x86@kernel.org
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Arnaldo Carvalho de Melo <acme@redhat.com>,
        Andi Kleen <ak@linux.intel.com>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        linux-kernel@vger.kernel.org, Yu-cheng Yu <yu-cheng.yu@intel.com>
References: <20200303045033.6137-1-whensungoes@gmail.com>
From:   Adrian Hunter <adrian.hunter@intel.com>
Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki,
 Business Identity Code: 0357606 - 4, Domiciled in Helsinki
Message-ID: <931d8779-8b77-b75f-bb3a-ee2f9d75f149@intel.com>
Date:   Tue, 3 Mar 2020 09:17:09 +0200
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101
 Thunderbird/68.5.0
MIME-Version: 1.0
In-Reply-To: <20200303045033.6137-1-whensungoes@gmail.com>
Content-Type: text/plain; charset=utf-8
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On 3/03/20 6:50 am, Mingbo Zhang wrote:
> Intel CET instructions are not described in the Intel SDM. When trying to
> get the instruction length, the following instructions get wrong (missing
> ModR/M byte).
> 
> RDSSPD r32
> RSDDPQ r64
> ENDBR32
> ENDBR64
> WRSSD r/m32, r32
> WRSSQ r/m64, r64
> 
> RDSSPD/Q and ENDBR32/64 use the same opcode (f3 0f 1e) slot, which is
> described in SDM as Reserved-NOP with no encoding characters, and got an
> empty slot in the opcode map. WRSSD/Q (0f 38 f6) also got an empty slot.

We have patches for that:

	https://lore.kernel.org/lkml/20200204171425.28073-1-yu-cheng.yu@intel.com/

But they have not yet been applied.  Arnaldo, could you take them?