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Date:   Mon, 5 Sep 2022 17:08:20 +0000
From:   Wei Liu <wei.liu@kernel.org>
To:     Vitaly Kuznetsov <vkuznets@redhat.com>
Cc:     kvm@vger.kernel.org, Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Michael Kelley <mikelley@microsoft.com>,
        Yuan Yao <yuan.yao@linux.intel.com>,
        Maxim Levitsky <mlevitsk@redhat.com>,
        linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org,
        Wei Liu <wei.liu@kernel.org>
Subject: Re: [PATCH v6 04/33] KVM: x86: Check for existing Hyper-V vCPU in
 kvm_hv_vcpu_init()
Message-ID: <20220905170820.yivhrivabsixj3ca@liuwe-devbox-debian-v2>
References: <20220830133737.1539624-1-vkuznets@redhat.com>
 <20220830133737.1539624-5-vkuznets@redhat.com>
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On Tue, Aug 30, 2022 at 03:37:08PM +0200, Vitaly Kuznetsov wrote:
> From: Sean Christopherson <seanjc@google.com>
> 
> When potentially allocating/initializing the Hyper-V vCPU struct, check
> for an existing instance in kvm_hv_vcpu_init() instead of requiring
> callers to perform the check.  Relying on callers to do the check is
> risky as it's all too easy for KVM to overwrite vcpu->arch.hyperv and
> leak memory, and it adds additional burden on callers without much
> benefit.
> 
> No functional change intended.
> 
> Signed-off-by: Sean Christopherson <seanjc@google.com>
> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>

Reviewed-by: Wei Liu <wei.liu@kernel.org>