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=-0.4 required=3.0 tests=BUG6152_INVALID_DATE_TZ_ABSURD,DKIMWL_WL_HIGH,DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,INVALID_DATE_TZ_ABSURD,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 3F0BFC5DF60 for ; Thu, 7 Nov 2019 09:10:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 019E42178F for ; Thu, 7 Nov 2019 09:10:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573117843; bh=yenYJT5xWwnA7zEx1Ag7YzfGX1pWIW4nsVZ5Wm/3S28=; h=To:Subject:Date:From:Cc:In-Reply-To:References:List-ID:From; b=FdlL4MDesU24MUX/BX41R34PKuwV1bypxsL3niqtYxDPD6C3150UuroKxF5tJSAuo ujSi+q9rt/HlrbfR1sIybAS3GEgjrekuzRO6oi/t3WHh7C/plByPA86Jqmhv65nbVg tbmSGY0qOMYzfnjIcrv9b/V1E2VFE2hBtEZVMRso= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387876AbfKGJKl (ORCPT ); Thu, 7 Nov 2019 04:10:41 -0500 Received: from inca-roads.misterjones.org ([213.251.177.50]:37968 "EHLO inca-roads.misterjones.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733142AbfKGJKl (ORCPT ); Thu, 7 Nov 2019 04:10:41 -0500 Received: from www-data by cheepnis.misterjones.org with local (Exim 4.80) (envelope-from ) id 1iSdoJ-0002WC-Ai; Thu, 07 Nov 2019 10:10:35 +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 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Date: Thu, 07 Nov 2019 10:19:56 +0109 From: Marc Zyngier Cc: , , , , , , , , , , vkuznets , , , KY Srinivasan , Sunil Muthuswamy , "boqun.feng" In-Reply-To: References: <1570129355-16005-1-git-send-email-mikelley@microsoft.com> <1570129355-16005-3-git-send-email-mikelley@microsoft.com> <8cdc86e5bcf861c74069e0d349910c94@www.loen.fr> Message-ID: 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 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2019-11-06 19:08, Michael Kelley wrote: > From: Marc Zyngier Sent: Wednesday, November 6, > 2019 2:20 AM >> >> 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. >> > > I'll go another round internally with the Hyper-V people on this > topic and impress upon them the desire of the Linux community to > have Hyper-V adopt the true spirit of the spec. But I know they are > fairly set in their approach at this point, regardless of the > technical > merits or lack thereof. Hyper-V is shipping and in use as a > commercial > product on ARM64 hardware, which makes it harder to change. I > hope we can find a way to avoid a complete impasse .... Hyper-V shipping with their own calling convention is fine by me. Linux having to implement multiple calling conventions because the Hyper-V folks refuse (for undisclosed reason) to adopt the standard isn't fine at all. HV can perfectly retain its interface for Windows or other things, but please *at least* implement the standard interface on which all existing operating systems rely. Thanks, M. -- Jazz is not dead. It just smells funny... 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,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 EDD1CC5DF60 for ; Thu, 7 Nov 2019 09:10:45 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) (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 C7B952187F for ; Thu, 7 Nov 2019 09:10:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C7B952187F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=driverdev-devel-bounces@linuxdriverproject.org Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id 9DE8285D57; Thu, 7 Nov 2019 09:10:45 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id yHpwM1IJ7-3Y; Thu, 7 Nov 2019 09:10:45 +0000 (UTC) Received: from ash.osuosl.org (ash.osuosl.org [140.211.166.34]) by whitealder.osuosl.org (Postfix) with ESMTP id ECA2385C57; Thu, 7 Nov 2019 09:10:44 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by ash.osuosl.org (Postfix) with ESMTP id 5E5B01BF2E4 for ; Thu, 7 Nov 2019 09:10:44 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id 542DA85B95 for ; Thu, 7 Nov 2019 09:10:44 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id pr1WiQ1avkHp for ; Thu, 7 Nov 2019 09:10:43 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from inca-roads.misterjones.org (inca-roads.misterjones.org [213.251.177.50]) by whitealder.osuosl.org (Postfix) with ESMTPS id 2879685C57 for ; Thu, 7 Nov 2019 09:10:43 +0000 (UTC) Received: from www-data by cheepnis.misterjones.org with local (Exim 4.80) (envelope-from ) id 1iSdoJ-0002WC-Ai; Thu, 07 Nov 2019 10:10:35 +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: Thu, 07 Nov 2019 10:19:56 +0109 From: Marc Zyngier In-Reply-To: References: <1570129355-16005-1-git-send-email-mikelley@microsoft.com> <1570129355-16005-3-git-send-email-mikelley@microsoft.com> <8cdc86e5bcf861c74069e0d349910c94@www.loen.fr> Message-ID: 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-BeenThere: driverdev-devel@linuxdriverproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux Driver Project Developer List 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 , will@kernel.org, Sunil Muthuswamy , linux-arm-kernel@lists.infradead.org Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: driverdev-devel-bounces@linuxdriverproject.org Sender: "devel" On 2019-11-06 19:08, Michael Kelley wrote: > From: Marc Zyngier Sent: Wednesday, November 6, > 2019 2:20 AM >> >> 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. >> > > I'll go another round internally with the Hyper-V people on this > topic and impress upon them the desire of the Linux community to > have Hyper-V adopt the true spirit of the spec. But I know they are > fairly set in their approach at this point, regardless of the > technical > merits or lack thereof. Hyper-V is shipping and in use as a > commercial > product on ARM64 hardware, which makes it harder to change. I > hope we can find a way to avoid a complete impasse .... Hyper-V shipping with their own calling convention is fine by me. Linux having to implement multiple calling conventions because the Hyper-V folks refuse (for undisclosed reason) to adopt the standard isn't fine at all. HV can perfectly retain its interface for Windows or other things, but please *at least* implement the standard interface on which all existing operating systems rely. Thanks, M. -- Jazz is not dead. It just smells funny... _______________________________________________ devel mailing list devel@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel 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 28F47C5DF61 for ; Thu, 7 Nov 2019 09:10:45 +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 E6D262178F for ; 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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 1iSdoS-0007oF-4J; Thu, 07 Nov 2019 09:10:44 +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 1iSdoO-0007ma-SW for linux-arm-kernel@lists.infradead.org; Thu, 07 Nov 2019 09:10:42 +0000 Received: from www-data by cheepnis.misterjones.org with local (Exim 4.80) (envelope-from ) id 1iSdoJ-0002WC-Ai; Thu, 07 Nov 2019 10:10:35 +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: Thu, 07 Nov 2019 10:19:56 +0109 From: Marc Zyngier In-Reply-To: References: <1570129355-16005-1-git-send-email-mikelley@microsoft.com> <1570129355-16005-3-git-send-email-mikelley@microsoft.com> <8cdc86e5bcf861c74069e0d349910c94@www.loen.fr> Message-ID: 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-20191107_011041_064978_58E75DA7 X-CRM114-Status: GOOD ( 11.64 ) 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 2019-11-06 19:08, Michael Kelley wrote: > From: Marc Zyngier Sent: Wednesday, November 6, > 2019 2:20 AM >> >> 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. >> > > I'll go another round internally with the Hyper-V people on this > topic and impress upon them the desire of the Linux community to > have Hyper-V adopt the true spirit of the spec. But I know they are > fairly set in their approach at this point, regardless of the > technical > merits or lack thereof. Hyper-V is shipping and in use as a > commercial > product on ARM64 hardware, which makes it harder to change. I > hope we can find a way to avoid a complete impasse .... Hyper-V shipping with their own calling convention is fine by me. Linux having to implement multiple calling conventions because the Hyper-V folks refuse (for undisclosed reason) to adopt the standard isn't fine at all. HV can perfectly retain its interface for Windows or other things, but please *at least* implement the standard interface on which all existing operating systems rely. 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