From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?ISO-8859-1?Q?Roger_Pau_Monn=E9?= <roger.pau@citrix.com>
Subject: Re: [PATCH] qemu-stubdom: prevent useless medium change
 [and 1 more messages]
Date: Fri, 7 Dec 2012 10:37:14 +0100
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To: Ian Jackson <Ian.Jackson@eu.citrix.com>
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On 06/12/12 13:37, Ian Jackson wrote:
> Roger Pau Monne writes ("[Xen-devel] [PATCH] qemu-stubdom: prevent useless medium change"):
>> qemu-stubdom was stripping the prefix from the "params" xenstore
>> key in xenstore_parse_domain_config, which was then saved stripped in
>> a variable. In xenstore_process_event we compare the "param" from
>> xenstore (not stripped) with the stripped "param" saved in the
>> variable, which leads to a medium change (even if there isn't any),
>> since we are comparing something like aio:/path/to/file with
>> /path/to/file. This only happens one time, since
>> xenstore_parse_domain_config is the only place where we strip the
>> prefix. The result of this bug is the following:
> 
> Roger Pau Monne writes ("Re: [Xen-devel] [PATCH] qemu-stubdom: prevent useless medium change"):
>> Yes, it's a can of worms indeed.
>>
>> The non-stubdom path is not modified, and the code changes (1st block of
>> the patch) are contained inside a #ifdef STUBDOM (which is not seen on
>> the patch itself, because it's already there).
> 
> Aha!  Indeed.
> 
> Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
> Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
> 
> This needs to go into 4.2 surely ?

Thanks, and yes, it should be backported to 4.2 stable.

> Ian.
>