Re: [tip:x86/urgent] x86/PAT: Fix Xorg regression on CPUs that don't support PAT

[Ian W MORRISON]

On 2 June 2017 at 00:48, Ian W MORRISON <ianwmorrison@xxxxxxxxx> wrote:
> On 6/1/17 5:49 PM, Ian W MORRISON wrote:
>> On 31 May 2017 at 10:53, Doug Smythies <dsmythies@xxxxxxxxx> wrote:
>>> Note Before:
>>> I might not have the address list correct, as I have re-created this
>>> e-mail from the web page archive, having found the thread after bisecting the
>>> kernel.
>>>
>>> On 2017.05.29 18:50:57 -0400 (EDT) Mikulas Patocka wrote:
>>>> On Sun, 28 May 2017, Andy Lutomirski wrote:
>>>>> On Sun, May 28, 2017 at 11:18 AM, Bernhard Held <berny156@xxxxxx> wrote:
>>>>>> Hi,
>>>>>>
>>>>>> this patch breaks the boot of my kernel. The last message is "Booting
>>>>>> the kernel.".
>>>
>>> It breaks my kernel boot also, and I know of at least two others with
>>> the same, or similar, problem as of kernel 4.12-rc3.
>>>
>>
>> Just to add that I cannot boot v4.12-rc3 kernel with any Intel Atom
>> (BYT and CHT) Intel Compute Sticks. Adding 'earlyprintk=efi' confirms
>> kernel panic with
>> [ 0.000000] Kernel panic - not syncing: x86/PAT: PAT enabled, but not
>> supported by secondary CPU
>>
>>
>> <snip>
>>
>
> Confirmed that following patch fixes boot of v4.12-rc3 for Intel Atom Compute Sticks:
>
> [PATCH] Fix X86_FEATURE_PAT regression bug
>

<snip>

And for the sake of completeness, the revert patch
(https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?h=x86/urgent)
also fixes the boot of v4.12-rc3 for Intel Atom Compute Sticks (as
expected and now tested - yay).