linux-kernel - Re: [PATCH v7 05/13] fat: make fat_update

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <87v8do6y8q.fsf@mail.parknet.co.jp>
Date:   Thu, 10 Aug 2023 00:17:57 +0900
From:   OGAWA Hirofumi <hirofumi@...l.parknet.co.jp>
To:     Jan Kara <jack@...e.cz>
Cc:     Jeff Layton <jlayton@...nel.org>,
        Alexander Viro <viro@...iv.linux.org.uk>,
        Christian Brauner <brauner@...nel.org>,
        Eric Van Hensbergen <ericvh@...nel.org>,
        Latchesar Ionkov <lucho@...kov.net>,
        Dominique Martinet <asmadeus@...ewreck.org>,
        Christian Schoenebeck <linux_oss@...debyte.com>,
        David Howells <dhowells@...hat.com>,
        Marc Dionne <marc.dionne@...istor.com>,
        Chris Mason <clm@...com>, Josef Bacik <josef@...icpanda.com>,
        David Sterba <dsterba@...e.com>, Xiubo Li <xiubli@...hat.com>,
        Ilya Dryomov <idryomov@...il.com>,
        Jan Harkes <jaharkes@...cmu.edu>, coda@...cmu.edu,
        Tyler Hicks <code@...icks.com>, Gao Xiang <xiang@...nel.org>,
        Chao Yu <chao@...nel.org>,
        Yue Hu <huyue2@...jj8bn.sched.sma.tdnsstic1.cn>,
        Jeffle Xu <jefflexu@...ux.alibaba.com>,
        Namjae Jeon <linkinjeon@...nel.org>,
        Sungjong Seo <sj1557.seo@...sung.com>,
        Jan Kara <jack@...e.com>, "Theodore Ts'o" <tytso@....edu>,
        Andreas Dilger <adilger.kernel@...ger.ca>,
        Jaegeuk Kim <jaegeuk@...nel.org>,
        Miklos Szeredi <miklos@...redi.hu>,
        Bob Peterson <rpeterso@...hat.com>,
        Andreas Gruenbacher <agruenba@...hat.com>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Tejun Heo <tj@...nel.org>,
        Trond Myklebust <trond.myklebust@...merspace.com>,
        Anna Schumaker <anna@...nel.org>,
        Konstantin Komarov <almaz.alexandrovich@...agon-software.com>,
        Mark Fasheh <mark@...heh.com>,
        Joel Becker <jlbec@...lplan.org>,
        Joseph Qi <joseph.qi@...ux.alibaba.com>,
        Mike Marshall <hubcap@...ibond.com>,
        Martin Brandenburg <martin@...ibond.com>,
        Luis Chamberlain <mcgrof@...nel.org>,
        Kees Cook <keescook@...omium.org>,
        Iurii Zaikin <yzaikin@...gle.com>,
        Steve French <sfrench@...ba.org>,
        Paulo Alcantara <pc@...guebit.com>,
        Ronnie Sahlberg <ronniesahlberg@...il.com>,
        Shyam Prasad N <sprasad@...rosoft.com>,
        Tom Talpey <tom@...pey.com>,
        Sergey Senozhatsky <senozhatsky@...omium.org>,
        Richard Weinberger <richard@....at>,
        Hans de Goede <hdegoede@...hat.com>,
        Hugh Dickins <hughd@...gle.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Amir Goldstein <amir73il@...il.com>,
        "Darrick J. Wong" <djwong@...nel.org>,
        Benjamin Coddington <bcodding@...hat.com>,
        linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
        v9fs@...ts.linux.dev, linux-afs@...ts.infradead.org,
        linux-btrfs@...r.kernel.org, ceph-devel@...r.kernel.org,
        codalist@...emann.coda.cs.cmu.edu, ecryptfs@...r.kernel.org,
        linux-erofs@...ts.ozlabs.org, linux-ext4@...r.kernel.org,
        linux-f2fs-devel@...ts.sourceforge.net, cluster-devel@...hat.com,
        linux-nfs@...r.kernel.org, ntfs3@...ts.linux.dev,
        ocfs2-devel@...ts.linux.dev, devel@...ts.orangefs.org,
        linux-cifs@...r.kernel.org, samba-technical@...ts.samba.org,
        linux-mtd@...ts.infradead.org, linux-mm@...ck.org,
        linux-unionfs@...r.kernel.org, linux-xfs@...r.kernel.org
Subject: Re: [PATCH v7 05/13] fat: make fat_update_time get its own timestamp

Jan Kara <jack@...e.cz> writes:

> Since you are talking past one another with Jeff let me chime in here :). I
> think you are worried about this hunk:

Right.

> -	if ((flags & S_VERSION) && inode_maybe_inc_iversion(inode, false))
> +	if ((flags & (S_VERSION|S_CTIME|S_MTIME)) && inode_maybe_inc_iversion(inode, false))
>  		dirty_flags |= I_DIRTY_SYNC;
>
> which makes the 'flags' test pass even if we just modified ctime or mtime.
> But do note the second part of the if - inode_maybe_inc_iversion() - so we
> are going to mark the inode dirty with I_DIRTY_SYNC only if someone queried
> iversion since the last time we have incremented it.
>
> So this hunk is not really changing how inode is marked dirty, it only
> changes how often we check whether iversion needs increment and that should
> be fine (and desirable). Hence lazytime isn't really broken by this in any
> way.

OK. However, then it doesn't explain what I asked. This is not same with
generic_update_time(), only FAT does.

If thinks it is right thing, why generic_update_time() doesn't? I said
first reply, this was from generic_update_time(). (Or I'm misreading
updated generic_update_time()?)

Thanks.
-- 
OGAWA Hirofumi <hirofumi@...l.parknet.co.jp>