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Subject: Re: [PATCH v20 28/30] LoongArch: KVM: Enable kvm config and add the
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To:     WANG Xuerui <kernel@xen0n.name>, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org
Cc:     Paolo Bonzini <pbonzini@redhat.com>,
        Huacai Chen <chenhuacai@kernel.org>,
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        loongarch@lists.linux.dev, Jens Axboe <axboe@kernel.dk>,
        Mark Brown <broonie@kernel.org>,
        Alex Deucher <alexander.deucher@amd.com>,
        Oliver Upton <oliver.upton@linux.dev>, maobibo@loongson.cn,
        Xi Ruoyao <xry111@xry111.site>,
        kernel test robot <lkp@intel.com>
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From:   zhaotianrui <zhaotianrui@loongson.cn>
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Date:   Tue, 12 Sep 2023 09:57:59 +0800
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在 2023/9/11 下午3:30, WANG Xuerui 写道:
> On 8/31/23 16:30, Tianrui Zhao wrote:
>> [snip]
>> +
>> +config AS_HAS_LVZ_EXTENSION
>> +    def_bool $(as-instr,hvcl 0)
>
> Upon closer look it looks like this piece could use some improvement 
> as well: while presence of "hvcl" indeed always implies full support 
> for LVZ instructions, "hvcl" however isn't used anywhere in the 
> series, so it's not trivially making sense. It may be better to test 
> for an instruction actually going to be used like "gcsrrd". What do 
> you think?
Thanks for your advice, and I think both "hvcl" and "gcsrrd" 
instructions which are supported by binutils mean that the cpu support 
LVZ extension, so I think they have the same meaning there.

Thanks
Tianrui Zhao