Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Subject: Re: [PATCH RFC] kvm: x86: Expose AVX512_BF16 feature to guest
To:     Jing Liu <jing2.liu@linux.intel.com>, kvm@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org, jing2.liu@intel.com
References: <1561029712-11848-1-git-send-email-jing2.liu@linux.intel.com>
 <1561029712-11848-2-git-send-email-jing2.liu@linux.intel.com>
From:   Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <fd861e94-3ea5-3976-9855-05375f869f00@redhat.com>
Date:   Thu, 20 Jun 2019 14:16:22 +0200
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101
 Thunderbird/60.6.1
MIME-Version: 1.0
In-Reply-To: <1561029712-11848-2-git-send-email-jing2.liu@linux.intel.com>
Content-Type: text/plain; charset=utf-8
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On 20/06/19 13:21, Jing Liu wrote:
> +		for (i = 1; i <= times; i++) {
> +			if (*nent >= maxnent)
> +				goto out;
> +			do_cpuid_1_ent(&entry[i], function, i);
> +			entry[i].eax &= F(AVX512_BF16);
> +			entry[i].ebx = 0;
> +			entry[i].ecx = 0;
> +			entry[i].edx = 0;
> +			entry[i].flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
> +			++*nent;

This woud be wrong for i > 1, so instead make this

	if (entry->eax >= 1)

and define F(AVX512_BF16) as a new constant kvm_cpuid_7_1_eax_features.

Paolo