From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ian Campbell <ian.campbell@citrix.com>
Subject: Re: [PATCH v2 16/18] libxl: introduce
	libxl_userdata_unlink
Date: Wed, 27 Aug 2014 03:16:59 +0100
Message-ID: <1409105819.28009.82.camel@citrix.com>
References: <1406744639-28782-1-git-send-email-wei.liu2@citrix.com>
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To: Wei Liu <wei.liu2@citrix.com>
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On Wed, 2014-07-30 at 19:23 +0100, Wei Liu wrote:
> +    CTX_LOCK;
> +    lock = libxl__lock_domain_data(gc, domid);
> +    if (!lock) {

This seems like a quirk which deserves commenting on since this lock
only protects a specific type of userdata, specifically the libxl-json
userdata.

Any app defined data is not actually protected by this lock in general.
I haven't yet seen the caller but it seems odd that the application
would be allowed to unlink the libxl-json file, so I'm not sure why this
function needs to worry about the lock (instead of insisting that the
libxl-internal caller deals with it)

Ian.