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=-5.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_SANE_1 autolearn=ham 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 281D7C35669 for ; Sat, 22 Feb 2020 00:23:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DCD992467D for ; Sat, 22 Feb 2020 00:23:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="T6LfVdYo" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726205AbgBVAX1 (ORCPT ); Fri, 21 Feb 2020 19:23:27 -0500 Received: from userp2130.oracle.com ([156.151.31.86]:33360 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726045AbgBVAX1 (ORCPT ); Fri, 21 Feb 2020 19:23:27 -0500 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 01M0KBkn008088; Sat, 22 Feb 2020 00:23:22 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : subject : message-id : references : mime-version : content-type : content-transfer-encoding : in-reply-to; s=corp-2020-01-29; bh=vDiPCHqXKwCE9vSLdBZ4WMbduef2QvIlgdwwC3JOIvM=; b=T6LfVdYoPihUE7gqUVy37s9NdsUEMRBiAztT8UPl2EMwLivTrDy0Uho+P2I1HvAjDDP4 zN/vklyjrVYlWYnQXepdiD2B21HFYJJ/umpPlewBpQV5T5D7iL3qT2I8hkry4P8Bl6r6 IOkOI7mfbClXMPMz7I8vKiCxkZu0Qpotkj25ySptNSHdReaDvF2M5nswZtCu1HuvJ5Cx eVsoUYJ75UZi1NmHq/MoHZ/EgcPwhQuiE+opVX4X1hT08JtHJhjwT9eYk/7uw+8WaoUb 2MHl8OI+SFbDHIJO6mpbOQkcviswzfAkmFBI83fBbrB+OnY2UqxXzLtGyfMV/waOvRJg +w== Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by userp2130.oracle.com with ESMTP id 2y8uddkj0f-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Sat, 22 Feb 2020 00:23:22 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 01M0HuuO071147; Sat, 22 Feb 2020 00:23:21 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserp3020.oracle.com with ESMTP id 2y8udrdje8-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Sat, 22 Feb 2020 00:23:21 +0000 Received: from abhmp0001.oracle.com (abhmp0001.oracle.com [141.146.116.7]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 01M0NK8j021690; Sat, 22 Feb 2020 00:23:20 GMT Received: from localhost (/10.145.179.117) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 21 Feb 2020 16:23:20 -0800 Date: Fri, 21 Feb 2020 16:23:19 -0800 From: "Darrick J. Wong" To: Christoph Hellwig , Linus Torvalds , Linux Kernel Mailing List , linux-pm@vger.kernel.org Subject: Re: Regression: hibernation is broken since e6bc9de714972cac34daa1dc1567ee48a47a9342 Message-ID: <20200222002319.GK9504@magnolia> References: <20200213172351.GA6747@dumbo> <20200213175753.GS6874@magnolia> <20200213183515.GA8798@dumbo> <20200213193410.GB6868@magnolia> <20200213194135.GF6870@magnolia> <20200214211523.GA32637@dumbo> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20200214211523.GA32637@dumbo> User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9538 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 mlxlogscore=999 phishscore=0 suspectscore=0 mlxscore=0 malwarescore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2002220000 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9538 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 impostorscore=0 mlxlogscore=999 malwarescore=0 mlxscore=0 suspectscore=0 priorityscore=1501 bulkscore=0 adultscore=0 spamscore=0 lowpriorityscore=0 clxscore=1015 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2002220000 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On Fri, Feb 14, 2020 at 10:15:24PM +0100, Domenico Andreoli wrote: > [ added linux-pm ] > > On Thu, Feb 13, 2020 at 11:41:35AM -0800, Darrick J. Wong wrote: > > On Thu, Feb 13, 2020 at 11:34:10AM -0800, Darrick J. Wong wrote: > > > > > > Well ... you could try the in-kernel hibernate (which I think is what > > > 'systemctl hibernate' does), though you'd lose the nifty features of > > > µswsusp. > > Indeed 'systemctl hibernate' works perfectly with v5.6-rc1 in my setup. > > > > In the end, though, I'll probably have to revert all those IS_SWAPFILE > > > checks (at least if CONFIG_HIBERNATION=y) since it's not fair to force > > > you to totally reconfigure your hibernation setup. > > > > Also, does the following partial revert fix uswsusp for you? It'll > > allow the direct writes that uswsusp wants to do, while leaving the rest > > (mmap writes) in place. > > > > --D > > > > diff --git a/fs/block_dev.c b/fs/block_dev.c > > index 69bf2fb6f7cd..077d9fa6b87d 100644 > > --- a/fs/block_dev.c > > +++ b/fs/block_dev.c > > @@ -2001,8 +2001,10 @@ ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from) > > if (bdev_read_only(I_BDEV(bd_inode))) > > return -EPERM; > > > > +#ifndef CONFIG_HIBERNATION > > if (IS_SWAPFILE(bd_inode)) > > return -ETXTBSY; > > +#endif > > This alone is enough to make uswsusp work again. > > I propose this alternative: > > --- a/fs/block_dev.c > +++ b/fs/block_dev.c > @@ -2001,7 +2001,8 @@ ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from) > if (bdev_read_only(I_BDEV(bd_inode))) > return -EPERM; > > - if (IS_SWAPFILE(bd_inode)) > + /* Hibernation might happen via uswsusp, let it write to the swap */ > + if (IS_SWAPFILE(bd_inode) && !IS_ENABLED(CONFIG_HIBERNATION)) > return -ETXTBSY; > > if (!iov_iter_count(from)) > > I looked for a more selective way to enable writes to swap at runtime, > so I tried with system_entering_hibernation() but it's not yet armed > at the point in which uswsusp wants to write to the swap and therefore > it does not work. > > --- a/fs/block_dev.c > +++ b/fs/block_dev.c > @@ -34,6 +34,7 @@ > #include > #include > #include > +#include > #include "internal.h" > > struct bdev_inode { > @@ -2001,7 +2002,8 @@ ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from) > if (bdev_read_only(I_BDEV(bd_inode))) > return -EPERM; > > - if (IS_SWAPFILE(bd_inode)) > + /* Hibernation might happen via uswsusp, let it write to the swap */ > + if (IS_SWAPFILE(bd_inode) && !system_entering_hibernation()) > return -ETXTBSY; > > if (!iov_iter_count(from)) > > > if (!iov_iter_count(from)) > > return 0; > > diff --git a/mm/filemap.c b/mm/filemap.c > > index 1784478270e1..3df3211abe25 100644 > > --- a/mm/filemap.c > > +++ b/mm/filemap.c > > @@ -2920,8 +2920,10 @@ inline ssize_t generic_write_checks(struct kiocb *iocb, struct iov_iter *from) > > loff_t count; > > int ret; > > > > +#ifndef CONFIG_HIBERNATION > > if (IS_SWAPFILE(inode)) > > return -ETXTBSY; > > +#endif > > > > if (!iov_iter_count(from)) > > return 0; > > The above is not needed in my case but I'm not sure it would not be > needed in some other configuration of uswsusp. Ok, third try. Does the following work? This is a little more selective in that it only disables the write protection on the swap device/file that uswusp is going to write to. --D diff --git a/kernel/power/user.c b/kernel/power/user.c index 77438954cc2b..a3ae9cbbfcf0 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -372,10 +372,17 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, */ swdev = new_decode_dev(swap_area.dev); if (swdev) { + struct block_device *bd; + offset = swap_area.offset; - data->swap = swap_type_of(swdev, offset, NULL); + data->swap = swap_type_of(swdev, offset, &bd); if (data->swap < 0) error = -ENODEV; + + inode_lock(bd->bd_inode); + bd->bd_inode->i_flags &= ~S_SWAPFILE; + inode_unlock(bd->bd_inode); + bdput(bd); } else { data->swap = -1; error = -EINVAL;