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

From: Dominik Brodowski
Date: Tue May 30 2017 - 13:24:32 EST


Same boot problem here (Intel(R) Core(TM) i5-5200U CPU on a Dell XPS 13),
git-bisected to the same patch...

On Mon, May 29, 2017 at 06:50:57PM -0400, Mikulas Patocka wrote:
> Please do the following three tests and test if the kernel boots.
>
> 1. use the PAT patch and revert the change to the function pat_enabled()
> - i.e. change it to the original:
> bool pat_enabled(void)
> {
> return !!__pat_enabled;
> }

No joy.

> 2. use the PAT patch and revert the change to the function pat_ap_init
> - i.e. change it to the original:
> static void pat_ap_init(u64 pat)
> {
> if (!boot_cpu_has(X86_FEATURE_PAT)) {

Joy.

> 3. use the full PAT patch and apply the below patch on the top of it.

No joy.


Best,
Dominik

Attachment: signature.asc
Description: PGP signature