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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 2B88CC1975A for ; Sun, 22 Mar 2020 07:14:26 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E3F7120774 for ; Sun, 22 Mar 2020 07:14:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E3F7120774 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=rjwysocki.net Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 801656B0003; Sun, 22 Mar 2020 03:14:25 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 78A876B0006; Sun, 22 Mar 2020 03:14:25 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 653996B0007; Sun, 22 Mar 2020 03:14:25 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0166.hostedemail.com [216.40.44.166]) by kanga.kvack.org (Postfix) with ESMTP id 46FAF6B0003 for ; Sun, 22 Mar 2020 03:14:25 -0400 (EDT) Received: from smtpin03.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 15E848248047 for ; Sun, 22 Mar 2020 07:14:25 +0000 (UTC) X-FDA: 76622134890.03.walk25_267c2be571328 X-HE-Tag: walk25_267c2be571328 X-Filterd-Recvd-Size: 2870 Received: from cloudserver094114.home.pl (cloudserver094114.home.pl [79.96.170.134]) by imf03.hostedemail.com (Postfix) with ESMTP for ; Sun, 22 Mar 2020 07:14:24 +0000 (UTC) Received: from 185.80.35.16 (185.80.35.16) (HELO kreacher.localnet) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer 0.83.341) id 9dd6359b34936204; Sun, 22 Mar 2020 08:14:22 +0100 From: "Rafael J. Wysocki" To: Domenico Andreoli Cc: "Darrick J. Wong" , "Rafael J. Wysocki" , Linux PM , Linux Memory Management List , linux-fsdevel@vger.kernel.org, mkleinsoft@gmail.com, Christoph Hellwig , Andrew Morton , Len Brown , Pavel Machek Subject: Re: [PATCH v2] hibernate: Allow uswsusp to write to swap Date: Sun, 22 Mar 2020 08:14:21 +0100 Message-ID: <5202091.FuziMeULnI@kreacher> In-Reply-To: <20200304170646.GA31552@dumbo> References: <20200304170646.GA31552@dumbo> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" 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: On Wednesday, March 4, 2020 6:06:46 PM CET Domenico Andreoli wrote: > From: Domenico Andreoli > > It turns out that there is one use case for programs being able to > write to swap devices, and that is the userspace hibernation code. > > Quick fix: disable the S_SWAPFILE check if hibernation is configured. > > Fixes: dc617f29dbe5 ("vfs: don't allow writes to swap files") > Reported-by: Domenico Andreoli > Reported-by: Marian Klein > Signed-off-by: Domenico Andreoli > > v2: > - use hibernation_available() instead of IS_ENABLED(CONFIG_HIBERNATE) > - make Fixes: point to the right commit This looks OK to me. Has it been taken care of already, or am I expected to apply it? > --- > fs/block_dev.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > Index: b/fs/block_dev.c > =================================================================== > --- 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 * > if (bdev_read_only(I_BDEV(bd_inode))) > return -EPERM; > > - if (IS_SWAPFILE(bd_inode)) > + /* uswsusp needs write permission to the swap */ > + if (IS_SWAPFILE(bd_inode) && !hibernation_available()) > return -ETXTBSY; > > if (!iov_iter_count(from)) >