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Date:   Fri, 9 Sep 2022 15:32:41 +0800
From:   Chao Gao <chao.gao@intel.com>
To:     <isaku.yamahata@intel.com>
CC:     <linux-kernel@vger.kernel.org>, <kvm@vger.kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        Marc Zyngier <maz@kernel.org>, Will Deacon <will@kernel.org>,
        Yuan Yao <yuan.yao@linux.intel.com>,
        <isaku.yamahata@gmail.com>, Kai Huang <kai.huang@intel.com>,
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        John Garry <john.garry@huawei.com>,
        Daniel Lezcano <daniel.lezcano@linaro.org>,
        "Huang Ying" <ying.huang@intel.com>,
        Huacai Chen <chenhuacai@kernel.org>
Subject: Re: [PATCH v4 17/26] KVM: Introduce a arch wrapper to check all
 processor compatibility
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On Thu, Sep 08, 2022 at 04:25:33PM -0700, isaku.yamahata@intel.com wrote:
>From: Isaku Yamahata <isaku.yamahata@intel.com>
>
>Introduce a arch wrapper to check all processor compatibility and define
>default implementation as weak symbol to keep the current logic.
>
>The hardware feature compatibility check is arch dependent, only x86 KVM
>does cpu feature check on all processors.  It doesn't make much sense to
>enforce the current implementation to invoke check function on each
>processors.  Introduce a arch callback,
>kvm_arch_check_processor_compat_all(), so that arch code can override it.
>
>Eventually feature check should be pushed down into arch callback,
>(kvm_arch_hardware_setup(), kvm_arch_online_cpu(), and kvm_arch_resume()),
>the two compatibility check, kvm_arch_check_processor_compat{,_all}(), will
>be eliminated.  This is a transitional step for it.
>
>Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>

Reviewed-by: Chao Gao <chao.gao@intel.com>

>+__weak int kvm_arch_check_processor_compat_all(void)

nit: int __weak