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Subject: Re: [PATCH v3 33/35] OvmfPkg: Introduce XenIoPvhDxe to initialize Grant Tables
To: Anthony PERARD <anthony.perard@citrix.com>
Cc: devel@edk2.groups.io, xen-devel@lists.xenproject.org,
 Ard Biesheuvel <ard.biesheuvel@linaro.org>,
 Jordan Justen <jordan.l.justen@intel.com>,
 Julien Grall <julien.grall@arm.com>
References: <20190704144233.27968-1-anthony.perard@citrix.com>
 <20190704144233.27968-34-anthony.perard@citrix.com>
 <4badd535-c23d-c64d-7bb3-fb42bbbf538a@redhat.com>
 <20190726160642.GG1242@perard.uk.xensource.com>
From: "Laszlo Ersek" <lersek@redhat.com>
Message-ID: <a2cc4fa2-becb-af51-92e7-81e30ee5a1a1@redhat.com>
Date: Fri, 26 Jul 2019 19:19:30 +0200
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On 07/26/19 18:06, Anthony PERARD wrote:
> On Wed, Jul 10, 2019 at 04:05:02PM +0200, Laszlo Ersek wrote:
>> On 07/04/19 16:42, Anthony PERARD wrote:

>>> +  if (State == NULL) {
>>> +    Status = EFI_OUT_OF_RESOURCES;
>>> +    goto Error;
>>> +  }
>>> +
>>> +  Allocation = AllocateReservedPages (XEN_GRANT_FRAMES);
>>
>> (5) So, again, please evaluate if this could simply be AllocatePages().
> 
> I would prefer to let know the operating system that those pages are
> potentially used, unless I'm sure OVMF has let know Xen that those
> pages don't contain the grant table anymore.
> 
> I'll probably try to make some changes in OVMF to allow to give back
> those pages, but for now I think keeping those pages as reserved will
> be good enough.

Fair enough!

Thanks,
Laszlo