From patchwork Tue May 19 23:24:28 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anchal Agarwal X-Patchwork-Id: 11558969 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8F4E614B7 for ; Tue, 19 May 2020 23:25:00 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 50C6920823 for ; Tue, 19 May 2020 23:25:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b="Zno3tRzq" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 50C6920823 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=amazon.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 3AE7A80021; Tue, 19 May 2020 19:24:59 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 3385F900003; Tue, 19 May 2020 19:24:59 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1FF3780021; Tue, 19 May 2020 19:24:59 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0095.hostedemail.com [216.40.44.95]) by kanga.kvack.org (Postfix) with ESMTP id 018A4900003 for ; Tue, 19 May 2020 19:24:58 -0400 (EDT) Received: from smtpin27.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id A8618824805A for ; Tue, 19 May 2020 23:24:58 +0000 (UTC) X-FDA: 76835051076.27.horse40_65a17c2185b27 X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,prvs=4015a1a96=anchalag@amazon.com,,RULES_HIT:30012:30045:30054:30056:30064:30069:30070:30083:30090,0,RBL:52.95.49.90:@amazon.com:.lbl8.mailshell.net-64.10.201.10 62.18.0.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:23,LUA_SUMMARY:none X-HE-Tag: horse40_65a17c2185b27 X-Filterd-Recvd-Size: 7554 Received: from smtp-fw-6002.amazon.com (smtp-fw-6002.amazon.com [52.95.49.90]) by imf27.hostedemail.com (Postfix) with ESMTP for ; Tue, 19 May 2020 23:24:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1589930698; x=1621466698; h=date:from:to:subject:message-id:mime-version; bh=sOfgRrPRmYHAfVrUOSXb1jwG6rejPn1YQXzhPKMaw1U=; b=Zno3tRzqCySeyGzd4HCkBCeo0lJfVOCMjEo6aqGqydve6c7cPBt+cjcg vXzVsV7ffCpDb1JSfJaPuE8ldfW/W8xSr5vz6tw4vCBMbhW5gDekZkQKh 88xxFlbk/8e4MXOajtiCZnXc0xyhU6NPxE0E+VsM6uZFIFDb/M1FzYYOZ 8=; IronPort-SDR: TapJ5+eP/s1RHA3K19MF7wVhCWSkQk3+kRa1I2OBkLAKB8EewWlyo02ycYQtyZZFMpV1Mo7QXf a/UcclI1rQNQ== X-IronPort-AV: E=Sophos;i="5.73,411,1583193600"; d="scan'208";a="31066594" Received: from iad12-co-svc-p1-lb1-vlan3.amazon.com (HELO email-inbound-relay-2b-c7131dcf.us-west-2.amazon.com) ([10.43.8.6]) by smtp-border-fw-out-6002.iad6.amazon.com with ESMTP; 19 May 2020 23:24:43 +0000 Received: from EX13MTAUEE002.ant.amazon.com (pdx4-ws-svc-p6-lb7-vlan2.pdx.amazon.com [10.170.41.162]) by email-inbound-relay-2b-c7131dcf.us-west-2.amazon.com (Postfix) with ESMTPS id A24D9A24BC; Tue, 19 May 2020 23:24:41 +0000 (UTC) Received: from EX13D08UEE003.ant.amazon.com (10.43.62.118) by EX13MTAUEE002.ant.amazon.com (10.43.62.24) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Tue, 19 May 2020 23:24:29 +0000 Received: from EX13MTAUEE002.ant.amazon.com (10.43.62.24) by EX13D08UEE003.ant.amazon.com (10.43.62.118) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Tue, 19 May 2020 23:24:29 +0000 Received: from dev-dsk-anchalag-2a-9c2d1d96.us-west-2.amazon.com (172.22.96.68) by mail-relay.amazon.com (10.43.62.224) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Tue, 19 May 2020 23:24:29 +0000 Received: by dev-dsk-anchalag-2a-9c2d1d96.us-west-2.amazon.com (Postfix, from userid 4335130) id DD57040712; Tue, 19 May 2020 23:24:28 +0000 (UTC) Date: Tue, 19 May 2020 23:24:28 +0000 From: Anchal Agarwal To: , , , , , , , , , , , , , , , , , , , , , , , , , , , Subject: [PATCH 00/12] Fix PM hibernation in Xen guests Message-ID: MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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 RFCV3 could be found here: https://lkml.org/lkml/2020/2/14/2789 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] " Anchal Agarwal (5): x86/xen: Introduce new function to map HYPERVISOR_shared_info on Resume genirq: Shutdown irq chips in suspend/resume during hibernation xen: Introduce wrapper for save/restore sched clock offset xen: Update sched clock offset to avoid system instability in hibernation PM / hibernate: update the resume offset on SNAPSHOT_SET_SWAP_AREA Munehisa Kamata (7): 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 xen/time: introduce xen_{save,restore}_steal_clock x86/xen: save and restore steal clock arch/x86/xen/enlighten_hvm.c | 8 ++ arch/x86/xen/suspend.c | 72 ++++++++++++++++++ arch/x86/xen/time.c | 18 ++++- 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 | 73 ++++++++++++++++++ drivers/xen/time.c | 29 ++++++- drivers/xen/xenbus/xenbus_probe.c | 99 +++++++++++++++++++----- include/linux/irq.h | 2 + include/xen/xen-ops.h | 8 ++ 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 +- 17 files changed, 536 insertions(+), 40 deletions(-)