From mboxrd@z Thu Jan  1 00:00:00 1970
From: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Subject: Re: [PATCH v2 3/3] paravirt: rename paravirt_enabled to
 paravirt_legacy
Date: Wed, 17 Feb 2016 16:21:56 -0500
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To: Borislav Petkov <bp@alien8.de>, "Luis R. Rodriguez" <mcgrof@kernel.org>
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On 02/17/2016 03:49 PM, Borislav Petkov wrote:
> On Wed, Feb 17, 2016 at 12:07:13PM -0800, Luis R. Rodriguez wrote:
>> OK so here's a wiki to keep track of progress of the difference uses:
>>
>> http://kernelnewbies.org/KernelProjects/remove-paravirt-enabled
>>
>> It seems we have a resolution one way or another for all except for
>> the use on arch/x86/mm/dump_pagetables.c, is that right?
>
> Why not?
>
> I think we should simply check the range as ffff800000000000 -
> ffff87ffffffffff is practically an ABI and nothing should be mapped
                                                     ^^^^^^^^^

That's exactly the point: if something is mapped it's an error for a 
non-PV kernel.

By removing paravirt_enabled() we may miss those errors. Worse, I think 
we may even crash while doing pagetable walk (although it's probably 
better to crash here than to use an unexpected translation in real code 
somewhere)

-boris


> there anyway. No need for paravirt_enabled() there either.
>