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Subject: Re: [PATCH] x86: perf: insn: Tweak opcode map for Intel CET
 instructions
From:   Adrian Hunter <adrian.hunter@intel.com>
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>,
        Jiri Olsa <jolsa@redhat.com>
References: <20200303045033.6137-1-whensungoes@gmail.com>
 <931d8779-8b77-b75f-bb3a-ee2f9d75f149@intel.com>
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Date:   Mon, 16 Mar 2020 09:10:49 +0200
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On 3/03/20 9:17 am, Adrian Hunter wrote:
> 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?
> 

Any takers?