r259580 breaks radeonkms

[Garrett Cooper]

> On Aug 6, 2014, at 9:52, Roger Pau Monné <royger at FreeBSD.org> wrote:
> 
>> On 06/08/14 16:35, Nathan Whitehorn wrote:
>> 
>> 
>>> On 2014-08-06 02:35, Roger Pau Monné wrote:
>>>> On 06/08/14 02:37, Nathan Whitehorn wrote:
>>>> Kernels with r269580 will panic when loading the radeonkms driver in
>>>> pmap_page_set_memattr(). This probably indicates a bug in radeonkms, but
>>>> the system is unusable in the meantime.
>>>> -Nathan
>>> 
>>> I seem to be able to load radeonkms just fine after r269580:
>> 
>> It's possible that it is related to actually using it, rather than
>> loading the module. I was only testing them together. I'm using vt and
>> the panic (page fault in kernel mode) occurs when TTM tries to set
>> memory attributes on some page while starting X. Before the panic, I see
>> all the normal Radeon module messages as you do, so the module seems to
>> have actually loaded correctly.  The KMS console also seems to be
>> functional enough to display the panic message, so I suspect it's X that
>> triggers it.
>> -Nathan
> 
> Please try the attached patch, it seems to solve the panic for me. It
> also includes a fix for Intel i915 gem, which I'm not able to test
> because I don't have the hardware.
> 
> Roger.
> 
> <0001-drm-fix-usage-of-vm_phys_fictitious_to_vm_page.patch>

David McKay confirmed that the patch worked for them on an intel GEM compatible chipset.
Cheers!
-Garrett