Konstantin Belousov d3e4d71f1d Handle pmap_enter() over an existing 4/2M page in KVA on i386.
The userspace case was already handled by pmap_allocpte().  For kernel
VA, page table page must exist, and demote cannot fail, so we need to
just call pmap_demote_pde().  Also note that due to the machine AS
layout, promotions in the KVA on i386 are highly unlikely, so this
change is mostly for completeness.

Reviewed by:	alc, markj
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
Differential revision:	https://reviews.freebsd.org/D8323
2016-10-28 11:53:22 +00:00
..