git: f4c6843ec2b9 - main - xen: use correct cache attributes for Xen specific memory regions

[John Baldwin]

On 8/12/21 12:24 AM, Roger Pau Monné wrote:
> The branch main has been updated by royger:
> 
> URL: https://cgit.FreeBSD.org/src/commit/?id=f4c6843ec2b9aa5eff475778fb000ed6278c5b77
> 
> commit f4c6843ec2b9aa5eff475778fb000ed6278c5b77
> Author:     Roger Pau Monné <royger at FreeBSD.org>
> AuthorDate: 2021-04-09 09:31:44 +0000
> Commit:     Roger Pau Monné <royger at FreeBSD.org>
> CommitDate: 2021-08-12 07:18:32 +0000
> 
>      xen: use correct cache attributes for Xen specific memory regions
>      
>      bus_activate_resource maps memory regions as uncacheable on x86, which
>      is more strict than required for regions allocated using xenmem_alloc,
>      so don't rely on bus_activate_resource and instead map the region
>      using pmap_mapdev_attr and VM_MEMATTR_XEN as the cache attribute.
>      
>      Sponsored by: Citrix Systems R&D

It would probably be cleaner to use bus_map_resource() for this instead.  It
would mean you would have to use a structure that writes to as the argument
to bus_read/write_* instead of using the resource directly.

-- 
John Baldwin