From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5CC2EC3DA66 for ; Fri, 25 Aug 2023 18:42:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:From:References:Cc:To: Subject:MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=7gYu7aLdnhjzvaNgBGV3z90JazSg3UD0td3b+VFZMf0=; b=uPTVr/7ytb8Nmz uDyMbqWxn11yQzdqHtBEHKfaz6UD2CurJnlJr/sx7ovxV1ttua2J3IOptSRlzmv/HCvx/xYeZ1esk 8iE0m9wDHQglbzPoM4TG1ftx71Om3Sr19xHbSvL7T/o09Vg/BGudCRBT4YFz1VIWgUW1bYIEL4QyF e5o8Jy1deVkLOSkV8MgmHOuYOAVBU/ytKc7f2l3GIsmNdPF9YIzqq1TaecM8VOPDbxXbUug0F2/j5 g5zBpiDBhFN4hnZ5Rd8ybGNi/BOiG7lsiRm0T0VAaOWP2r27/S2YTf1GJPKrzPqV+pVblUREQMCar iWKruD/ZQVlBCmOnoqQA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qZbka-005sxK-0K; Fri, 25 Aug 2023 18:41:40 +0000 Received: from linux.microsoft.com ([13.77.154.182]) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qZbkX-005swm-1e for linux-arm-kernel@lists.infradead.org; Fri, 25 Aug 2023 18:41:38 +0000 Received: from [192.168.0.5] (71-212-112-68.tukw.qwest.net [71.212.112.68]) by linux.microsoft.com (Postfix) with ESMTPSA id 7763A2127C98; Fri, 25 Aug 2023 11:41:36 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 7763A2127C98 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1692988896; bh=r4TNOTdwvr0jLYHJLt0g9pFNyHVSneTmcu12aApJMls=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=CgVQ+RvETEOWpVRpx8KiKE6S7h1NeeymYBzRxdMaFA3TVUbKkkQk5+2saGc8Qj6zD H94BKZd9cf5DzxzyeGfp4KVVOJ76AlhCmMMn9UhKTAB4/baPsZEOZocCWujTCiz3Wa dsT+VvykH2pGZWcPD96moBVjOwyRNyYW7StxfslY= Message-ID: <0909fb87-9370-4c59-b7ea-9ca673d456b3@linux.microsoft.com> Date: Fri, 25 Aug 2023 11:41:35 -0700 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 15/15] Drivers: hv: Add modules to expose /dev/mshv to VMMs running on Hyper-V Content-Language: en-US To: Boqun Feng Cc: linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, x86@kernel.org, linux-arm-kernel@lists.infradead.org, linux-arch@vger.kernel.org, patches@lists.linux.dev, mikelley@microsoft.com, kys@microsoft.com, wei.liu@kernel.org, haiyangz@microsoft.com, decui@microsoft.com, apais@linux.microsoft.com, Tianyu.Lan@microsoft.com, ssengar@linux.microsoft.com, mukeshrathor@microsoft.com, stanislav.kinsburskiy@gmail.com, jinankjain@linux.microsoft.com, vkuznets@redhat.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, will@kernel.org, catalin.marinas@arm.com References: <1692309711-5573-1-git-send-email-nunodasneves@linux.microsoft.com> <1692309711-5573-16-git-send-email-nunodasneves@linux.microsoft.com> From: Nuno Das Neves In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230825_114137_595904_92D364A1 X-CRM114-Status: GOOD ( 14.44 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 8/24/2023 11:31 AM, Boqun Feng wrote: > On Thu, Aug 17, 2023 at 03:01:51PM -0700, Nuno Das Neves wrote: > [...] >> +static long >> +mshv_dev_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) >> +{ >> + switch (ioctl) { >> + case MSHV_CHECK_EXTENSION: >> + return mshv_ioctl_check_extension((void __user *)arg); >> + case MSHV_CREATE_PARTITION: >> + return mshv.create_partition((void __user *)arg); >> + case MSHV_CREATE_VTL: >> + return mshv.create_vtl((void __user *)arg); >> + } >> + > > Shouldn't we also have a MSHV_GET_API_VERSION ioctl similar as KVM? So > that in the future when we change these ioctl interfaces or semantics, > we can bump up the API version to avoid breaking userspace? > Note that we contribute and maintain support for this driver in Cloud Hypervisor, so we control both sides of this API - if we break userspace we can fix it ourselves. For now the MSHV_CHECK_EXTENSION ioctl is sufficient - we can pass it MSHV_CAP_CORE_API_STABLE, and it will return 0 to indicate that the API is not yet stable. A version check may be useful in the future, but is not needed right now. Thanks Nuno Das Neves _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel