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 X-Spam-Level: X-Spam-Status: No, score=-0.3 required=3.0 tests=BUG6152_INVALID_DATE_TZ_ABSURD,DKIMWL_WL_HIGH,DKIM_SIGNED,DKIM_VALID, INVALID_DATE_TZ_ABSURD,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 14384C5DF62 for ; Wed, 6 Nov 2019 10:19:20 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id D90A8217F4 for ; Wed, 6 Nov 2019 10:19:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="VumhQ9FG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D90A8217F4 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender:Content-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:Message-ID:References:In-Reply-To:From:Date: MIME-Version:Subject:To:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=YhRldontKgg93/nTrGIi7xSYpk9YFyIKGa61YJ3bZ/4=; b=VumhQ9FGu9ns6lbGGHE4unKIA 3Wix0owrsN5SK3bGI56NuFNJX8aoTcT/M100ppAYtTmIHauqahMuI0Fue+GWlhuxHa9dy4vTJfZGr NIeLnrEN+zKRKaOv6jg9OX9TAc20WfqqChLARoh1QS4yB0x4+2flmD9Jv+mgzh7/EIYK2WTlvR0sh kbdnj9ab9/HEiz4+z6MEkgO5tjaTo3fmYgcfaPU8H+oCe0Nf2RELGTKBC2Toxe431JjrhZaHLeVIS RGKbiW16iQdmJ91SQegYR54DJ3QnOJPOJqkRrA64y8t3GNy1IPdkF68xckbxAfGFkapJENyq3Umyj gyJAQO/Iw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iSIPH-0006yX-44; Wed, 06 Nov 2019 10:19:19 +0000 Received: from inca-roads.misterjones.org ([213.251.177.50]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iSIPC-0006xy-AR for linux-arm-kernel@lists.infradead.org; Wed, 06 Nov 2019 10:19:17 +0000 Received: from www-data by cheepnis.misterjones.org with local (Exim 4.80) (envelope-from ) id 1iSIP7-0007q5-Ff; Wed, 06 Nov 2019 11:19:09 +0100 To: Michael Kelley Subject: Re: [PATCH v5 2/8] arm64: hyperv: Add hypercall and register access functions X-PHP-Originating-Script: 0:main.inc MIME-Version: 1.0 Date: Wed, 06 Nov 2019 11:28:30 +0109 From: Marc Zyngier In-Reply-To: <1570129355-16005-3-git-send-email-mikelley@microsoft.com> References: <1570129355-16005-1-git-send-email-mikelley@microsoft.com> <1570129355-16005-3-git-send-email-mikelley@microsoft.com> Message-ID: <8cdc86e5bcf861c74069e0d349910c94@www.loen.fr> X-Sender: maz@kernel.org User-Agent: Roundcube Webmail/0.7.2 X-SA-Exim-Connect-IP: X-SA-Exim-Rcpt-To: mikelley@microsoft.com, will@kernel.org, catalin.marinas@arm.com, mark.rutland@arm.com, linux-arm-kernel@lists.infradead.org, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, devel@linuxdriverproject.org, olaf@aepfle.de, apw@canonical.com, vkuznets@redhat.com, jasowang@redhat.com, marcelo.cerri@canonical.com, kys@microsoft.com, sunilmut@microsoft.com, boqun.feng@gmail.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on cheepnis.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191106_021916_070655_F49C1145 X-CRM114-Status: UNSURE ( 7.02 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mark.rutland@arm.com, linux-hyperv@vger.kernel.org, "boqun.feng" , catalin.marinas@arm.com, jasowang@redhat.com, linux-kernel@vger.kernel.org, marcelo.cerri@canonical.com, olaf@aepfle.de, gregkh@linuxfoundation.org, apw@canonical.com, devel@linuxdriverproject.org, vkuznets , KY Srinivasan , will@kernel.org, Sunil Muthuswamy , linux-arm-kernel@lists.infradead.org Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2019-10-03 20:12, Michael Kelley wrote: > Add ARM64-specific code to make Hyper-V hypercalls and to > access virtual processor synthetic registers via hypercalls. > Hypercalls use a Hyper-V specific calling sequence with a non-zero > immediate value per Section 2.9 of the SMC Calling Convention > spec. I find this "following the spec by actively sidestepping it" counter productive. You (or rather the Hyper-V people) are reinventing the wheel (of the slightly square variety) instead of using the standard that the whole of the ARM ecosystem seems happy to take advantage of. I wonder what is the rational for this. If something doesn't quite work for Hyper-V, I think we'd all like to know. Thanks, M. -- Jazz is not dead. It just smells funny... _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel