[src/trunk]: src/sys/arch/x86/x86 Xen/i386PAE is special, in that top-level e...

[bouyer <bouyer%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/d4660c19ee4e
branches:  trunk
changeset: 824998:d4660c19ee4e
user:      bouyer <bouyer%NetBSD.org@localhost>
date:      Sun Jun 25 22:16:46 2017 +0000

description:
Xen/i386PAE is special, in that top-level entries are not in per-pmap
tables but per-CPU pages. pmap_alloc_level() takes care of making new
entries actives when the kernel pmap is updated, so always use pmap_kernel()
is this case too.

diffstat:

 sys/arch/x86/x86/pmap.c |  14 ++++++++++----
 1 files changed, 10 insertions(+), 4 deletions(-)

diffs (49 lines):

diff -r 43f9ccdad0e2 -r d4660c19ee4e sys/arch/x86/x86/pmap.c
--- a/sys/arch/x86/x86/pmap.c   Sun Jun 25 20:22:32 2017 +0000
+++ b/sys/arch/x86/x86/pmap.c   Sun Jun 25 22:16:46 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: pmap.c,v 1.253 2017/06/25 12:42:40 bouyer Exp $        */
+/*     $NetBSD: pmap.c,v 1.254 2017/06/25 22:16:46 bouyer Exp $        */
 
 /*
  * Copyright (c) 2008, 2010, 2016, 2017 The NetBSD Foundation, Inc.
@@ -171,7 +171,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.253 2017/06/25 12:42:40 bouyer Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.254 2017/06/25 22:16:46 bouyer Exp $");
 
 #include "opt_user_ldt.h"
 #include "opt_lockdebug.h"
@@ -4430,8 +4430,8 @@
                needed_kptp[i] = target_nptp - nkptp[i];
        }
 
-#if defined(XEN) && defined(__x86_64__)
-       /* only pmap_kernel() has kernel entries */
+#if defined(XEN) && (defined(__x86_64__) || defined(PAE))
+       /* only pmap_kernel(), or the per-cpu map, has kernel entries */
        cpm = kpm;
 #else
        /* Get the current pmap */
@@ -4453,6 +4453,11 @@
                /* nothing, kernel entries are never entered in user pmap */
 #else /* __x86_64__ */
                int pdkidx;
+#ifndef PAE
+               /*
+                * for PAE this is not needed, because pmap_alloc_level()
+                * already did update the per-CPU tables
+                */
                if (cpm != kpm) {
                        for (pdkidx = PDIR_SLOT_KERN + old;
                            pdkidx < PDIR_SLOT_KERN + nkptp[PTP_LEVELS - 1];
@@ -4462,6 +4467,7 @@
                        }
                        pmap_pte_flush();
                }
+#endif /* !PAE */
 
                mutex_enter(&pmaps_lock);
                LIST_FOREACH(pm, &pmaps, pm_list) {