Re: [RFC PATCH v3 12/24] x86/mm: Modify ptep_set_wrprotect and pmdp_set_wrprotect for _PAGE_DIRTY_SW

[Dave Hansen]

On 08/30/2018 07:38 AM, Yu-cheng Yu wrote:
> +	 * Some processors can start a write, but ending up seeing
> +	 * a read-only PTE by the time they get to the Dirty bit.
> +	 * In this case, they will set the Dirty bit, leaving a
> +	 * read-only, Dirty PTE which looks like a Shadow Stack PTE.
> +	 *
> +	 * However, this behavior has been improved and will not occur
> +	 * on processors supporting Shadow Stacks.  Without this
> +	 * guarantee, a transition to a non-present PTE and flush the
> +	 * TLB would be needed.

Did we publicly document this behavior anywhere?  I can't seem to find it.