From patchwork Fri Jan 28 21:32:59 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefano Stabellini X-Patchwork-Id: 12729143 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 lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 AE84FC4332F for ; Fri, 28 Jan 2022 21:33:28 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.262145.454279 (Exim 4.92) (envelope-from ) id 1nDYrh-0001MM-So; Fri, 28 Jan 2022 21:33:05 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 262145.454279; Fri, 28 Jan 2022 21:33:05 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1nDYrh-0001MF-PT; Fri, 28 Jan 2022 21:33:05 +0000 Received: by outflank-mailman (input) for mailman id 262145; Fri, 28 Jan 2022 21:33:04 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1nDYrg-0001M8-TQ for xen-devel@lists.xenproject.org; Fri, 28 Jan 2022 21:33:04 +0000 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id de4c123f-8081-11ec-8f75-fffcc8bd4f1a; Fri, 28 Jan 2022 22:33:02 +0100 (CET) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 8FC6F61E9A; Fri, 28 Jan 2022 21:33:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E1245C340EC; Fri, 28 Jan 2022 21:32:59 +0000 (UTC) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: de4c123f-8081-11ec-8f75-fffcc8bd4f1a DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1643405580; bh=DVSVQE2+B4BrH2Gb3Fiu+UcJh3jXsRSt4BAmn6YYQMc=; h=Date:From:To:cc:Subject:From; b=bt5ZjhrZL5AMzy1XGcXe0zYVbDMWZt+kqcn9jj+dGfpuPUsszANM5yHdx2+pXW/MC ifsmoLv0xQQGxBBPVOtvd+WpqodBfyJFZomt9Zmj2b43327Aa7SEdfdJbig8wHKDdG jv+bcg/OqIj72StE0tL7Hw0uho9eTw0aYBwFAvdtpXEB53Oyot4RWu/iI8GNe2Ydap J9vfsu2VjQo0jGqPfYDFOXmGJmPv4UVeLUdzjfFIiMMyWnR1c7PLKaPUzRS5e2C9Ik KbHDnaMfoTgATbzQ8h0VxqcW85zcT7tNPo4qNP8pSU8LOuCReLdUJRBavtfMu07TBl MGMpNhjwr0MdQ== Date: Fri, 28 Jan 2022 13:32:59 -0800 (PST) From: Stefano Stabellini X-X-Sender: sstabellini@ubuntu-linux-20-04-desktop To: xen-devel@lists.xenproject.org cc: sstabellini@kernel.org, jgross@suse.com, Bertrand.Marquis@arm.com, julien@xen.org, Volodymyr_Babchuk@epam.com Subject: [PATCH v3 0/5] dom0less PV drivers Message-ID: User-Agent: Alpine 2.22 (DEB 394 2020-01-19) MIME-Version: 1.0 Hi all, Currently dom0less guests cannot use PV drivers because they don't have access to xenstore. Also, the hypervisor node in device tree is missing so they don't detect that they are running on Xen (thus, they don't try to enable PV interfaces.) This patch series enables dom0less guests (on ARM) to use PV drivers. Instead of initializing xenstore immediately at boot, dom0less guests get access to xenstore later. They delay the initialization until they receive a notification via the xenstore event channel (which is available at boot.) An example workflow is as follows: - all domains start in parallel, dom0less guests are immediately running - when dom0 is up and running, the init-dom0less application is called - dom0less guests receive the notification and initialize xenstore - now xl network-attach/disk-attach works as expected for dom0less domUs The patch series introduces a new dom0less device tree option "xen,enhanced" (in the Xen device tree) to specify whether PV interfaces should be enabled/disabled for the dom0less guest. Cheers, Stefano Luca Miccio (4): xen: make evtchn_alloc_unbound public xen/arm: configure dom0less domain for enabling xenstore after boot xenstored: send an evtchn notification on introduce_domain tools: add example application to initialize dom0less PV drivers Stefano Stabellini (1): xen: introduce xen,enhanced dom0less property docs/misc/arm/device-tree/booting.txt | 18 +++ tools/helpers/Makefile | 13 ++ tools/helpers/init-dom0less.c | 269 ++++++++++++++++++++++++++++++++++ tools/xenstore/xenstored_domain.c | 3 + xen/arch/arm/domain_build.c | 49 +++++++ xen/arch/arm/include/asm/kernel.h | 3 + xen/common/event_channel.c | 13 +- xen/include/xen/event.h | 3 + 8 files changed, 366 insertions(+), 5 deletions(-) create mode 100644 tools/helpers/init-dom0less.c