Subject: Re: [PATCH v2 27/29] LoongArch: KVM: Implement vcpu world switch
To:     Paolo Bonzini <pbonzini@redhat.com>
References: <20230220065735.1282809-1-zhaotianrui@loongson.cn>
 <20230220065735.1282809-28-zhaotianrui@loongson.cn>
 <50575db8-efb8-2d56-5dd9-fe4318db2af3@redhat.com>
Cc:     Huacai Chen <chenhuacai@kernel.org>,
        WANG Xuerui <kernel@xen0n.name>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        loongarch@lists.linux.dev, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org, 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
From:   Tianrui Zhao <zhaotianrui@loongson.cn>
Message-ID: <e33bbe6b-fb21-7473-cb8a-5068b44f21ce@loongson.cn>
Date:   Tue, 21 Feb 2023 21:00:26 +0800
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在 2023年02月21日 15:45, Paolo Bonzini 写道:
> On 2/20/23 07:57, Tianrui Zhao wrote:
>> +    /* Load Guest gprs */
>> +    ld.d    $r1,   \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 1)
>> +    ld.d    $r2,   \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 2)
>> +    ld.d    $r3,   \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 3)
>> +    ld.d    $r4,   \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 4)
>> +    ld.d    $r5,   \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 5)
>> +    ld.d    $r7,   \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 7)
>> +    ld.d    $r8,   \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 8)
>> +    ld.d    $r9,   \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 9)
>> +    ld.d    $r10,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 10)
>> +    ld.d    $r11,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 11)
>> +    ld.d    $r12,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 12)
>> +    ld.d    $r13,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 13)
>> +    ld.d    $r14,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 14)
>> +    ld.d    $r15,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 15)
>> +    ld.d    $r16,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 16)
>> +    ld.d    $r17,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 17)
>> +    ld.d    $r18,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 18)
>> +    ld.d    $r19,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 19)
>> +    ld.d    $r20,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 20)
>> +    ld.d    $r21,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 21)
>> +    ld.d    $r22,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 22)
>> +    ld.d    $r23,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 23)
>> +    ld.d    $r24,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 24)
>> +    ld.d    $r25,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 25)
>> +    ld.d    $r26,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 26)
>> +    ld.d    $r27,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 27)
>> +    ld.d    $r28,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 28)
>> +    ld.d    $r29,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 29)
>> +    ld.d    $r30,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 30)
>> +    ld.d    $r31,  \KVM_ARCH,  (KVM_ARCH_GGPR + 8 * 31)
>> +    /* Load KVM_ARCH register */
>> +    ld.d    \KVM_ARCH, \KVM_ARCH, (KVM_ARCH_GGPR + 8 * \GPRNUM)
>
> This in practice relies on KVM_ARCH being a2 so please remove the 
> KVM_ARCH and GPRNUM arguments from the macro; just replace \KVM_ARCH 
> with a2 as needed.
>
> Also, in these ld.d and st.d sequences you may want to use the ABI 
> names instead of the rNN names, so it's clearer that you are skipping 
> the KVM_ARCH register.
>
> Paolo

Thanks, I will use a2 to replace the KVM_ARCH and remove the GPRNUM 
argument.

Thanks
Tianrui Zhao