From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:37057)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <asmetanin@odin.com>) id 1a1dMW-0007Xj-Eb
	for qemu-devel@nongnu.org; Wed, 25 Nov 2015 11:56:09 -0500
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <asmetanin@odin.com>) id 1a1dMT-0000Bz-9E
	for qemu-devel@nongnu.org; Wed, 25 Nov 2015 11:56:08 -0500
Received: from relay.parallels.com ([195.214.232.42]:50766)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <asmetanin@odin.com>) id 1a1dMT-0000Au-1C
	for qemu-devel@nongnu.org; Wed, 25 Nov 2015 11:56:05 -0500
References: <1448464821-8199-1-git-send-email-asmetanin@virtuozzo.com>
	<1448464821-8199-7-git-send-email-asmetanin@virtuozzo.com>
	<5655E748.4080503@redhat.com>
From: Andrey Smetanin <asmetanin@virtuozzo.com>
Message-ID: <5655E800.5030309@virtuozzo.com>
Date: Wed, 25 Nov 2015 19:55:28 +0300
MIME-Version: 1.0
In-Reply-To: <5655E748.4080503@redhat.com>
Content-Type: text/plain; charset="windows-1252"; format=flowed
Content-Transfer-Encoding: 7bit
Subject: Re: [Qemu-devel] [PATCH v1 6/7] kvm/x86: Hyper-V SynIC message slot
 pending clearing at SINT ack
Reply-To: asmetanin@virtuozzo.com
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Paolo Bonzini <pbonzini@redhat.com>, kvm@vger.kernel.org
Cc: Gleb Natapov <gleb@kernel.org>, Haiyang Zhang <haiyangz@microsoft.com>, qemu-devel@nongnu.org, Roman Kagan <rkagan@virtuozzo.com>, "Denis V. Lunev" <den@openvz.org>, Vitaly Kuznetsov <vkuznets@redhat.com>, "K. Y. Srinivasan" <kys@microsoft.com>



On 11/25/2015 07:52 PM, Paolo Bonzini wrote:
>
>
> On 25/11/2015 16:20, Andrey Smetanin wrote:
>> +static void synic_clear_sint_msg_pending(struct kvm_vcpu_hv_synic *synic,
>> +					u32 sint)
>> +{
>> +	struct kvm_vcpu *vcpu = synic_to_vcpu(synic);
>> +	struct page *page;
>> +	gpa_t gpa;
>> +	struct hv_message *msg;
>> +	struct hv_message_page *msg_page;
>> +
>> +	gpa = synic->msg_page & PAGE_MASK;
>> +	page = kvm_vcpu_gfn_to_page(vcpu, gpa >> PAGE_SHIFT);
>> +	if (is_error_page(page)) {
>> +		vcpu_err(vcpu, "Hyper-V SynIC can't get msg page, gpa 0x%llx\n",
>> +			 gpa);
>> +		return;
>> +	}
>> +	msg_page = kmap_atomic(page);
>
> But the message page is not being pinned, is it?
>
Actually I don't know anything about pinning.
Is it pinning against page swapping ?
Could you please clarify and provide an API to use in this case ?
> Paolo
>
>> +	msg = &msg_page->sint_message[sint];
>> +	msg->header.message_flags.msg_pending = 0;
>> +
>> +	kunmap_atomic(msg_page);
>> +	kvm_release_page_dirty(page);
>> +	kvm_vcpu_mark_page_dirty(vcpu, gpa >> PAGE_SHIFT);
>> +}
>> +