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Subject: Re: [PATCH 4/7] KVM: SVM: hyper-v: Nested enlightenments in VMCB
To:     Paolo Bonzini <pbonzini@redhat.com>,
        Lan Tianyu <Tianyu.Lan@microsoft.com>,
        Michael Kelley <mikelley@microsoft.com>,
        Sean Christopherson <seanjc@google.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>, Wei Liu <wei.liu@kernel.org>,
        Stephen Hemminger <sthemmin@microsoft.com>,
        Haiyang Zhang <haiyangz@microsoft.com>
Cc:     "H. Peter Anvin" <hpa@zytor.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "K. Y. Srinivasan" <kys@microsoft.com>, x86@kernel.org,
        kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-hyperv@vger.kernel.org, viremana@linux.microsoft.com
References: <cover.1617804573.git.viremana@linux.microsoft.com>
 <e9de12a81ab31613fb55d5c1308ca0ca050ced4c.1617804573.git.viremana@linux.microsoft.com>
 <5927967d-c5a2-6df9-9aff-4b92c207df09@redhat.com>
From:   Vineeth Pillai <viremana@linux.microsoft.com>
Message-ID: <1ae328de-718c-dfa3-f5af-e765d953d841@linux.microsoft.com>
Date:   Fri, 9 Apr 2021 08:24:39 -0400
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On 4/8/21 11:44 AM, Paolo Bonzini wrote:
> On 07/04/21 16:41, Vineeth Pillai wrote:
>> +#define VMCB_ALL_CLEAN_MASK (__CLEAN_MASK | (1U << 
>> VMCB_HV_NESTED_ENLIGHTENMENTS))
>> +#else
>> +#define VMCB_ALL_CLEAN_MASK __CLEAN_MASK
>> +#endif
>
> I think this should depend on whether KVM is running on top of 
> Hyper-V; not on whether KVM is *compiled* with Hyper-V support.
>
> So you should turn VMCB_ALL_CLEAN_MASK into a __read_mostly variable.
Will do.

Thanks,
Vineeth