> -Original Message-
> From: Xen-devel [mailto:xen-devel-boun...@lists.xenproject.org] On Behalf
> Of Jan Beulich
> Sent: 25 October 2018 15:28
> To: Paul Durrant
> Cc: Andrew Cooper ; Wei Liu
> ; xen-devel
> Subject: Re: [Xen-devel] [PATCH v2] x86/mm/p2m: don't
>>> On 25.10.18 at 16:36, wrote:
> On 25/10/18 15:28, Jan Beulich wrote:
> On 17.10.18 at 16:24, wrote:
>>> --- a/xen/arch/x86/mm/p2m.c
>>> +++ b/xen/arch/x86/mm/p2m.c
>>> @@ -2081,14 +2081,11 @@ static unsigned int mmio_order(const struct domain
> *d,
>>>
On 25/10/18 15:28, Jan Beulich wrote:
On 17.10.18 at 16:24, wrote:
>> --- a/xen/arch/x86/mm/p2m.c
>> +++ b/xen/arch/x86/mm/p2m.c
>> @@ -2081,14 +2081,11 @@ static unsigned int mmio_order(const struct domain
>> *d,
>> unsigned long start_fn, unsigned long nr)
>>> On 17.10.18 at 16:24, wrote:
> --- a/xen/arch/x86/mm/p2m.c
> +++ b/xen/arch/x86/mm/p2m.c
> @@ -2081,14 +2081,11 @@ static unsigned int mmio_order(const struct domain *d,
> unsigned long start_fn, unsigned long nr)
> {
> /*
> - * Note that the
The P2M common code currently restricts the MMIO mapping order of any
domain with IOMMU mappings, but that is not using shared tables, to 4k.
This has been shown to have a huge performance cost when passing through
a PCI device with a very large BAR (e.g. NVIDIA P40), increasing the guest
boot
