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Date:   Tue, 20 Jul 2021 13:35:14 +0000
From:   Wei Liu <wei.liu@kernel.org>
To:     Praveen Kumar <kumarpraveen@linux.microsoft.com>
Cc:     Wei Liu <wei.liu@kernel.org>, linux-hyperv@vger.kernel.org,
        linux-kernel@vger.kernel.org, kys@microsoft.com,
        haiyangz@microsoft.com, sthemmin@microsoft.com,
        decui@microsoft.com, tglx@linutronix.de, mingo@redhat.com,
        bp@alien8.de, x86@kernel.org, hpa@zytor.com,
        viremana@linux.microsoft.com, sunilmut@microsoft.com,
        nunodasneves@linux.microsoft.com
Subject: Re: [PATCH] hyperv: root partition faults writing to VP ASSIST MSR
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References: <20210719185126.3740-1-kumarpraveen@linux.microsoft.com>
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On Tue, Jul 20, 2021 at 06:55:56PM +0530, Praveen Kumar wrote:
[...]
> > 
> >> +	if (hv_root_partition &&
> >> +	    ms_hyperv.features & HV_MSR_APIC_ACCESS_AVAILABLE) {
> > 
> > Is HV_MSR_APIC_ACCESS_AVAILABLE a root only flag? Shouldn't non-root
> > kernel check this too?
> 
> Yes, you are right. Will update this in v2. thanks.

Please split adding this check to its own patch.

Ideally one patch only does one thing.

Wei.

> 
> > 
> > Wei.
> > 
> 
> Regards,
> 
> ~Praveen.