From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 782351DE3A4; Thu, 27 Feb 2025 18:50:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740682232; cv=none; b=tYtu/78MqZeepEOoksvPR8jrliROE9N42smaAZZbg3L0ZynJK0Ip7TDvUx01N0Rog39Lhb249JkBM/6cOeXZkgDht0N5YpKylE4rzVgMM5+wzr92L+ElxpenovHsSklRbnUrseEFF4rzw2k/mVfJMNBu7iXOPZDhgacrsepT3vM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740682232; c=relaxed/simple; bh=F1lTmqgjHYJPjcmbtxE/n3iAXCq4SZkVmt5nqUeZPXY=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=UUAbgYd+WIY89QNALCaSsR9uBKRLzqDEcEVKRwFBqz1yAXKXFwNuyPrcMg2/EtvjN+qyyOmRCQeWDoUsIIJ/2YQKb2qi0uK56A4ybbuB+pWwKnIbT1zTkolVWhTfDRm77C5UBEAoI/6jPwMfVII+7dCL0dRsU9AWhkOsncMCeYU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=FNbW9YBu; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="FNbW9YBu" Received: from [10.137.184.60] (unknown [131.107.160.188]) by linux.microsoft.com (Postfix) with ESMTPSA id 9B421210D0D8; Thu, 27 Feb 2025 10:50:30 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 9B421210D0D8 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1740682231; bh=dHwZT1w8oWRsXa8H/+DiZfRcRSkOTyh9HqlMdGrYI/Q=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=FNbW9YBuPokWfkhV8B0zMJtN5945pEMQP20InF/WOW6hK0iLB5iSFm7uJafeCDov9 ygoVc1l10LfK0HlQbcUkAzGjyXWi8ArYK0CYgWh0b61j196eOqg//F7JMoJtHcRzGr /mlcu6UBD8g84zdCQtIgCvdToz5xVsg4gg8RkKH4= Message-ID: Date: Thu, 27 Feb 2025 10:50:30 -0800 Precedence: bulk X-Mailing-List: linux-hyperv@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 10/10] Drivers: hv: Introduce mshv_root module to expose /dev/mshv to VMMs To: Nuno Das Neves , linux-hyperv@vger.kernel.org, x86@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-acpi@vger.kernel.org Cc: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, mhklinux@outlook.com, decui@microsoft.com, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, daniel.lezcano@linaro.org, joro@8bytes.org, robin.murphy@arm.com, arnd@arndb.de, jinankjain@linux.microsoft.com, muminulrussell@gmail.com, skinsburskii@linux.microsoft.com, mrathor@linux.microsoft.com, ssengar@linux.microsoft.com, apais@linux.microsoft.com, Tianyu.Lan@microsoft.com, stanislav.kinsburskiy@gmail.com, gregkh@linuxfoundation.org, vkuznets@redhat.com, prapal@linux.microsoft.com, muislam@microsoft.com, anrayabh@linux.microsoft.com, rafael@kernel.org, lenb@kernel.org, corbet@lwn.net References: <1740611284-27506-1-git-send-email-nunodasneves@linux.microsoft.com> <1740611284-27506-11-git-send-email-nunodasneves@linux.microsoft.com> Content-Language: en-US From: Roman Kisel In-Reply-To: <1740611284-27506-11-git-send-email-nunodasneves@linux.microsoft.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 2/26/2025 3:08 PM, Nuno Das Neves wrote: > Provide a set of IOCTLs for creating and managing child partitions when > running as root partition on Hyper-V. The new driver is enabled via > CONFIG_MSHV_ROOT. > [...] As I understood, the changes fall into these buckets: 1. Partition management (VPs and memory). Built of the top of fd's which looks as the right approach. There is ref counting etc. 2. Scheduling. Here, there is the mature KVM and Xen code to find inspiration in. Xen being the Type 1 hypervisor should likely be closer to MSHV in my understanding. 3. IOCTL code allocation. Not sure how this is allocated yet given that the patch series has been through a multi-year review, that must be settled by now. 4. IOCTLs themselves. The majority just marshals data to the hypervisor. Despite the rather large size of the patch, I spot-checked the places where I have the chance to make an informed decision, and could not find anything that'd stand out as suspicious to me. Going to extrapolate that the patch itself should be good enough. Given that this code has been in development and validation for a few years, I'd vote to merge it. That will also enable upstreaming the rest of the VTL mode code that powers Azure Boost (https://github.com/microsoft/OHCL-Linux-Kernel) Reviewed-by: Roman Kisel -- Thank you, Roman