Re: [PATCHv5 07/19] x86/mm: Mask out KeyID bits from page table entry pfn

From: Dave Hansen
Date: Thu Jul 19 2018 - 10:19:11 EST


On 07/19/2018 02:54 AM, Kirill A. Shutemov wrote:
> On Wed, Jul 18, 2018 at 04:13:20PM -0700, Dave Hansen wrote:
>> On 07/17/2018 04:20 AM, Kirill A. Shutemov wrote:
>>> + } else {
>>> + /*
>>> + * Reset __PHYSICAL_MASK.
>>> + * Maybe needed if there's inconsistent configuation
>>> + * between CPUs.
>>> + */
>>> + physical_mask = (1ULL << __PHYSICAL_MASK_SHIFT) - 1;
>>> + }
>> This seems like an appropriate place for a WARN_ON(). Either that, or
>> axe this code.
> There's pr_err_once() above in the function.

Do you mean for the (tme_activate != tme_activate_cpu0) check?

But that's about double-activating this feature. This check is about an
inconsistent configuration between two CPUs which seems totally different.

Could you explain?