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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 DC4AEC433DF for ; Thu, 2 Jul 2020 18:22:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B7F23208C7 for ; Thu, 2 Jul 2020 18:22:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b="Im/bqyFM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727993AbgGBSWC (ORCPT ); Thu, 2 Jul 2020 14:22:02 -0400 Received: from smtp-fw-9102.amazon.com ([207.171.184.29]:3113 "EHLO smtp-fw-9102.amazon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726980AbgGBSV7 (ORCPT ); Thu, 2 Jul 2020 14:21:59 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1593714118; x=1625250118; h=date:from:to:subject:message-id:mime-version; bh=cs2EUulVYmJiGWKGk3tjkuDldhZPB72HbPIIjHU97dk=; b=Im/bqyFMVIZ9ZEysI5y0Exifv8AoyVt0F4JvyFQ6wg6oYkamRQOYZl2r KHg786tY44AsAQso/39AmMSrWgJIzcbau7KHMpmTXX8T6FjunccNyfeFG Rzp111s4wYKSnb23u/8rZZfVov9Hqi8ynOMey40eR9EyAHHltz77uzJNQ w=; IronPort-SDR: QkQyYmP3nGLpAiOJsMdMVFBarx/mgZsiYn5B7jwFEKwaWLU7F40e7pi00Eb1XlqW0VHybjgWcA d/KKpJe7YxXg== X-IronPort-AV: E=Sophos;i="5.75,305,1589241600"; d="scan'208";a="56964454" Received: from sea32-co-svc-lb4-vlan3.sea.corp.amazon.com (HELO email-inbound-relay-1d-74cf8b49.us-east-1.amazon.com) ([10.47.23.38]) by smtp-border-fw-out-9102.sea19.amazon.com with ESMTP; 02 Jul 2020 18:21:50 +0000 Received: from EX13MTAUEB002.ant.amazon.com (iad55-ws-svc-p15-lb9-vlan2.iad.amazon.com [10.40.159.162]) by email-inbound-relay-1d-74cf8b49.us-east-1.amazon.com (Postfix) with ESMTPS id BDE57C05B9; Thu, 2 Jul 2020 18:21:43 +0000 (UTC) Received: from EX13D08UEB002.ant.amazon.com (10.43.60.107) by EX13MTAUEB002.ant.amazon.com (10.43.60.12) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Thu, 2 Jul 2020 18:21:25 +0000 Received: from EX13MTAUEA002.ant.amazon.com (10.43.61.77) by EX13D08UEB002.ant.amazon.com (10.43.60.107) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Thu, 2 Jul 2020 18:21:25 +0000 Received: from dev-dsk-anchalag-2a-9c2d1d96.us-west-2.amazon.com (172.22.96.68) by mail-relay.amazon.com (10.43.61.169) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Thu, 2 Jul 2020 18:21:25 +0000 Received: by dev-dsk-anchalag-2a-9c2d1d96.us-west-2.amazon.com (Postfix, from userid 4335130) id 896F240844; Thu, 2 Jul 2020 18:21:24 +0000 (UTC) Date: Thu, 2 Jul 2020 18:21:24 +0000 From: Anchal Agarwal To: , , , , , , , , , , , , , , , , , , , , , , , , , , , Subject: [PATCH v2 00/11] Fix PM hibernation in Xen guests Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Hello, This series fixes PM hibernation for hvm guests running on xen hypervisor. The running guest could now be hibernated and resumed successfully at a later time. The fixes for PM hibernation are added to block and network device drivers i.e xen-blkfront and xen-netfront. Any other driver that needs to add S4 support if not already, can follow same method of introducing freeze/thaw/restore callbacks. The patches had been tested against upstream kernel and xen4.11. Large scale testing is also done on Xen based Amazon EC2 instances. All this testing involved running memory exhausting workload in the background. Doing guest hibernation does not involve any support from hypervisor and this way guest has complete control over its state. Infrastructure restrictions for saving up guest state can be overcome by guest initiated hibernation. These patches were send out as RFC before and all the feedback had been incorporated in the patches. The last v1 could be found here: [v1]: https://lkml.org/lkml/2020/5/19/1312 All comments and feedback from v1 had been incorporated in v2 series. Any comments/suggestions are welcome Known issues: 1.KASLR causes intermittent hibernation failures. VM fails to resumes and has to be restarted. I will investigate this issue separately and shouldn't be a blocker for this patch series. 2. During hibernation, I observed sometimes that freezing of tasks fails due to busy XFS workqueuei[xfs-cil/xfs-sync]. This is also intermittent may be 1 out of 200 runs and hibernation is aborted in this case. Re-trying hibernation may work. Also, this is a known issue with hibernation and some filesystems like XFS has been discussed by the community for years with not an effectve resolution at this point. Testing How to: --------------- 1. Setup xen hypervisor on a physical machine[ I used Ubuntu 16.04 +upstream xen-4.11] 2. Bring up a HVM guest w/t kernel compiled with hibernation patches [I used ubuntu18.04 netboot bionic images and also Amazon Linux on-prem images]. 3. Create a swap file size=RAM size 4. Update grub parameters and reboot 5. Trigger pm-hibernation from within the VM Example: Set up a file-backed swap space. Swap file size>=Total memory on the system sudo dd if=/dev/zero of=/swap bs=$(( 1024 * 1024 )) count=4096 # 4096MiB sudo chmod 600 /swap sudo mkswap /swap sudo swapon /swap Update resume device/resume offset in grub if using swap file: resume=/dev/xvda1 resume_offset=200704 no_console_suspend=1 Execute: -------- sudo pm-hibernate OR echo disk > /sys/power/state && echo reboot > /sys/power/disk Compute resume offset code: " #!/usr/bin/env python import sys import array import fcntl #swap file f = open(sys.argv[1], 'r') buf = array.array('L', [0]) #FIBMAP ret = fcntl.ioctl(f.fileno(), 0x01, buf) print buf[0] " Aleksei Besogonov (1): PM / hibernate: update the resume offset on SNAPSHOT_SET_SWAP_AREA Anchal Agarwal (4): x86/xen: Introduce new function to map HYPERVISOR_shared_info on Resume x86/xen: save and restore steal clock during PM hibernation xen: Introduce wrapper for save/restore sched clock offset xen: Update sched clock offset to avoid system instability in hibernation Munehisa Kamata (5): xen/manage: keep track of the on-going suspend mode xenbus: add freeze/thaw/restore callbacks support x86/xen: add system core suspend and resume callbacks xen-blkfront: add callbacks for PM suspend and hibernation xen-netfront: add callbacks for PM suspend and hibernation Thomas Gleixner (1): genirq: Shutdown irq chips in suspend/resume during hibernation arch/x86/xen/enlighten_hvm.c | 7 ++ arch/x86/xen/suspend.c | 53 +++++++++++++ arch/x86/xen/time.c | 15 +++- arch/x86/xen/xen-ops.h | 3 + drivers/block/xen-blkfront.c | 122 +++++++++++++++++++++++++++++- drivers/net/xen-netfront.c | 98 +++++++++++++++++++++++- drivers/xen/events/events_base.c | 1 + drivers/xen/manage.c | 60 +++++++++++++++ drivers/xen/xenbus/xenbus_probe.c | 96 +++++++++++++++++++---- include/linux/irq.h | 2 + include/xen/xen-ops.h | 3 + include/xen/xenbus.h | 3 + kernel/irq/chip.c | 2 +- kernel/irq/internals.h | 1 + kernel/irq/pm.c | 31 +++++--- kernel/power/user.c | 6 +- 16 files changed, 470 insertions(+), 33 deletions(-) -- 2.20.1