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=-5.3 required=3.0 tests=BAYES_00,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 31346C43461 for ; Fri, 11 Sep 2020 20:45:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D9DBC207FB for ; Fri, 11 Sep 2020 20:45:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b="idhg3pi2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725867AbgIKUpB (ORCPT ); Fri, 11 Sep 2020 16:45:01 -0400 Received: from smtp-fw-4101.amazon.com ([72.21.198.25]:6677 "EHLO smtp-fw-4101.amazon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725803AbgIKUpA (ORCPT ); Fri, 11 Sep 2020 16:45:00 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1599857098; x=1631393098; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=M8uCPr9eXi5AxRmIWKQnXR89z2m5VaOqvl9N9mhNTFA=; b=idhg3pi2y+YASPdmM/RLQ2ZOeSMcCCw/IHgDmIEZ/mU/9g/8ajUgLbpq SoTC+Y2sMrVH2yFejT4RWf87BMhYEHgVE/6ip4NHINuViUBU38UrIUWy5 Oe+Va2C31/q94mIbt3sZQp0EpVKRDo4JBJSo1zxYzFZBYI/xjkOu+XUWT A=; X-IronPort-AV: E=Sophos;i="5.76,417,1592870400"; d="scan'208";a="53535315" Received: from iad12-co-svc-p1-lb1-vlan3.amazon.com (HELO email-inbound-relay-2b-baacba05.us-west-2.amazon.com) ([10.43.8.6]) by smtp-border-fw-out-4101.iad4.amazon.com with ESMTP; 11 Sep 2020 20:44:55 +0000 Received: from EX13MTAUWB001.ant.amazon.com (pdx4-ws-svc-p6-lb7-vlan2.pdx.amazon.com [10.170.41.162]) by email-inbound-relay-2b-baacba05.us-west-2.amazon.com (Postfix) with ESMTPS id 209E5A1D19; Fri, 11 Sep 2020 20:44:53 +0000 (UTC) Received: from EX13D05UWB002.ant.amazon.com (10.43.161.50) by EX13MTAUWB001.ant.amazon.com (10.43.161.249) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Fri, 11 Sep 2020 20:44:48 +0000 Received: from EX13MTAUWB001.ant.amazon.com (10.43.161.207) by EX13D05UWB002.ant.amazon.com (10.43.161.50) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Fri, 11 Sep 2020 20:44:47 +0000 Received: from dev-dsk-anchalag-2a-9c2d1d96.us-west-2.amazon.com (172.22.96.68) by mail-relay.amazon.com (10.43.161.249) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Fri, 11 Sep 2020 20:44:47 +0000 Received: by dev-dsk-anchalag-2a-9c2d1d96.us-west-2.amazon.com (Postfix, from userid 4335130) id D03A640770; Fri, 11 Sep 2020 20:44:47 +0000 (UTC) Date: Fri, 11 Sep 2020 20:44:47 +0000 From: Anchal Agarwal To: "Rafael J. Wysocki" CC: Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , "the arch/x86 maintainers" , Boris Ostrovsky , Juergen Gross , Linux PM , Linux Memory Management List , "Kamata, Munehisa" , "Stefano Stabellini" , Konrad Rzeszutek Wilk , , Jens Axboe , David Miller , "Rafael J. Wysocki" , Len Brown , Pavel Machek , Peter Zijlstra , Eduardo Valentin , "Singh, Balbir" , , Vitaly Kuznetsov , netdev , Linux Kernel Mailing List , David Woodhouse , "Benjamin Herrenschmidt" Subject: Re: [PATCH v3 00/11] Fix PM hibernation in Xen guests Message-ID: <20200911204447.GA23729@dev-dsk-anchalag-2a-9c2d1d96.us-west-2.amazon.com> References: <20200828182640.GA20719@dev-dsk-anchalag-2a-9c2d1d96.us-west-2.amazon.com> <20200828183945.GA22160@dev-dsk-anchalag-2a-9c2d1d96.us-west-2.amazon.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20200828183945.GA22160@dev-dsk-anchalag-2a-9c2d1d96.us-west-2.amazon.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Aug 28, 2020 at 06:39:45PM +0000, Anchal Agarwal wrote: > On Fri, Aug 28, 2020 at 08:29:24PM +0200, Rafael J. Wysocki wrote: > > CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you can confirm the sender and know the content is safe. > > > > > > > > On Fri, Aug 28, 2020 at 8:26 PM Anchal Agarwal wrote: > > > > > > On Fri, Aug 21, 2020 at 10:22:43PM +0000, Anchal Agarwal wrote: > > > > 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 & v2 could be found here: > > > > > > > > [v1]: https://lkml.org/lkml/2020/5/19/1312 > > > > [v2]: https://lkml.org/lkml/2020/7/2/995 > > > > All comments and feedback from v2 had been incorporated in v3 series. > > > > > > > > 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 | 63 ++++++++++++++++++++ > > > > arch/x86/xen/time.c | 15 ++++- > > > > arch/x86/xen/xen-ops.h | 3 + > > > > drivers/block/xen-blkfront.c | 122 ++++++++++++++++++++++++++++++++++++-- > > > > drivers/net/xen-netfront.c | 96 +++++++++++++++++++++++++++++- > > > > drivers/xen/events/events_base.c | 1 + > > > > drivers/xen/manage.c | 46 ++++++++++++++ > > > > 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 | 7 ++- > > > > 16 files changed, 464 insertions(+), 34 deletions(-) > > > > > > > > -- > > > > 2.16.6 > > > > > > > A gentle ping on the series in case there is any more feedback or can we plan to > > > merge this? I can then send the series with minor fixes pointed by tglx@ > > > > Some more time, please! > > > Sure happy to answer any more questions and fix more BUGS!! > > -- > Anchal > A gentle ping on this one again! -- Anchal