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From: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <56EAC420.6090809@redhat.com>
Date: Thu, 17 Mar 2016 15:50:08 +0100
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Subject: Re: [Qemu-devel] [PATCH v2] vl.c: disallow command line fw cfg
 without opt/
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To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Laszlo Ersek <lersek@redhat.com>, "Gabriel L. Somlo" <somlo@cmu.edu>, Gerd Hoffmann <kraxel@redhat.com>, Markus Armbruster <armbru@redhat.com>, qemu-devel@nongnu.org



On 17/03/2016 15:17, Michael S. Tsirkin wrote:
> On Thu, Mar 17, 2016 at 02:55:52PM +0100, Paolo Bonzini wrote:
>>
>>
>> On 17/03/2016 14:49, Michael S. Tsirkin wrote:
>>>> On 17/03/2016 14:13, Michael S. Tsirkin wrote:
>>>>>
>>>>> QEMU command line:
>>>>> 	A. -fw-cfg RFQDN/PATH prepends usr/. So users will not get conflicts
>>>>> 	   with QEMU hardware
>>>>
>>>> Alternative: no need to prepend usr/, I think.
>>>
>>> I personally dislike telling user "do X". I don't see a reason not to be
>>> friendly and do X. The rare case where users do not want X can be
>>> easily enabled.
>>
>> I wouldn't include usr/ at all in the paths.  The RFQDN recommendation
>> is enough to avoid clashes with etc/ and opt/.
> 
> Yes but then we need a blacklist.

Can't the blacklist be as simple as "org.qemu/*", plus some handling of
legacy "etc/*"?

We'd need special handling of "etc/*" anyway because SeaBIOS is using it
(Gerd's usecase) and you certainly don't want to use
org.qemu/unsupported/etc/XYZ hacks for that.

Paolo