Re: [PATCH for 4.5 v8 1/1] Add mmio_hole

[Don Slutz <dslutz@verizon.com>]

On 10/22/14 07:21, Ian Campbell wrote:
> On Tue, 2014-10-21 at 08:42 -0400, Don Slutz wrote:
>> If you add enough PCI devices then all mmio may not fit below 4G
>> which may not be the layout the user wanted. This allows you to
>> increase the below 4G address space that PCI devices can use and
>> therefore in more cases not have any mmio that is above 4G.
>>
>> There are real PCI cards that do not support mmio over 4G, so if you
>> want to emulate them precisely, you may also need to increase the
>> space below 4G for them. There are drivers for these cards that also
>> do not work if they have their mmio space mapped above 4G.
>>
>> This allows growing the MMIO hole to the size needed.
>>
>> This may help with using pci passthru and HVM.
>>
>> In the tools this is named mmio_hole_memkb.
>>
>> Signed-off-by: Don Slutz <dslutz@verizon.com>
> For the tools side: Acked-by: Ian Campbell <ian.campbell@citrix.com>
>
> Has this had a release exception? Or acks for the hvmloader side of
> things?
>

On Tue, 14 Oct 2014 11:56:22 -0400, Konrad Rzeszutek Wilk said:

> I am OK with this patch going in Xen 4.5 (as a release-manager)
> but it can't go anywhere unless there is an Ack/Review.


On Mon, 20 Oct 2014 15:10:25 +0100, George Dunlap said:

> I haven't done a full review, but all of my previous concerns have
> been addressed:

> Acked-by: George Dunlap <george.dunlap@eu.citrix.com>


This was on v7.  There is no change to tools/firmware/* from v7 to v8.  
So as I said:


Changes from v7 to v8:
...

   George Dunlap
     Acked-by: George Dunlap<george.dunlap@eu.citrix.com>
       Did not add do changes to many parts.
       No change to tools/firmware/* so I think it still
         applies there.


Hope this is enough for you.

>> +        /*
>> +         * At the moment qemu-xen can't deal with relocated memory regions.
>> +         * It's too close to the release to make a proper fix; for now,
> This isn't really accurate any more.

Yes.

> No need for a v9 for this, and it would be inappropriate to change it in
> what is otherwise a code motion part of the patch.

Great.

    -Don Slutz

>> +         * only allow the MMIO hole to grow large enough to move guest memory
>> +         * if we're running qemu-traditional.  Items that don't fit will be
>> +         * relocated into the 64-bit address space.
> Ian.
>