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From:   "NeilBrown" <neilb@suse.de>
To:     "Jeff Layton" <jlayton@kernel.org>
Cc:     "J. Bruce Fields" <bfields@fieldses.org>,
        "Theodore Ts'o" <tytso@mit.edu>, "Jan Kara" <jack@suse.cz>,
        adilger.kernel@dilger.ca, djwong@kernel.org, david@fromorbit.com,
        trondmy@hammerspace.com, viro@zeniv.linux.org.uk,
        zohar@linux.ibm.com, xiubli@redhat.com, chuck.lever@oracle.com,
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        linux-man@vger.kernel.org, linux-api@vger.kernel.org,
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        linux-xfs@vger.kernel.org
Subject: Re: [man-pages RFC PATCH v4] statx, inode: document the new
 STATX_INO_VERSION field
In-reply-to: <44efe219dbf511492b21a653905448d43d0f3363.camel@kernel.org>
References: <79aaf122743a295ddab9525d9847ac767a3942aa.camel@kernel.org>,
 <20220907125211.GB17729@fieldses.org>,
 <771650a814ab1ff4dc5473d679936b747d9b6cf5.camel@kernel.org>,
 <20220907135153.qvgibskeuz427abw@quack3>,
 <166259786233.30452.5417306132987966849@noble.neil.brown.name>,
 <20220908083326.3xsanzk7hy3ff4qs@quack3>, <YxoIjV50xXKiLdL9@mit.edu>,
 <02928a8c5718590bea5739b13d6b6ebe66cac577.camel@kernel.org>,
 <20220908155605.GD8951@fieldses.org>,
 <9e06c506fd6b3e3118da0ec24276e85ea3ee45a1.camel@kernel.org>,
 <20220908182252.GA18939@fieldses.org>,
 <44efe219dbf511492b21a653905448d43d0f3363.camel@kernel.org>
Date:   Sun, 11 Sep 2022 08:13:11 +1000
Message-id: <166284799157.30452.4308111193560234334@noble.neil.brown.name>
Precedence: bulk

On Fri, 09 Sep 2022, Jeff Layton wrote:
> 
> The machine crashes and comes back up, and we get a query for i_version
> and it comes back as X. Fine, it's an old version. Now there is a write.
> What do we do to ensure that the new value doesn't collide with X+1? 

(I missed this bit in my earlier reply..)

How is it "Fine" to see an old version?
The file could have changed without the version changing.
And I thought one of the goals of the crash-count was to be able to
provide a monotonic change id.

NeilBrown