Module Name: src
Committed By: maxv
Date: Thu Jun 15 07:05:32 UTC 2017
Modified Files:
src/sys/arch/x86/x86: pmap.c
Log Message:
Limit the size of the direct map with a 2MB granularity (instead of 1GB).
This way if there's a computation error somewhere we will fault earlier
instead of letting the cpu access non-present physmem - which may cause
some bizarre behavior.
To generate a diff of this commit:
cvs rdiff -u -r1.247 -r1.248 src/sys/arch/x86/x86/pmap.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/x86/x86/pmap.c
diff -u src/sys/arch/x86/x86/pmap.c:1.247 src/sys/arch/x86/x86/pmap.c:1.248
--- src/sys/arch/x86/x86/pmap.c:1.247 Thu Jun 15 06:32:52 2017
+++ src/sys/arch/x86/x86/pmap.c Thu Jun 15 07:05:32 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: pmap.c,v 1.247 2017/06/15 06:32:52 maxv Exp $ */
+/* $NetBSD: pmap.c,v 1.248 2017/06/15 07:05:32 maxv 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 1.247 2017/06/15 06:32:52 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.248 2017/06/15 07:05:32 maxv Exp $");
#include "opt_user_ldt.h"
#include "opt_lockdebug.h"
@@ -1443,7 +1443,8 @@ pmap_init_directmap(struct pmap *kpm)
pt_entry_t *pte;
pd_entry_t *pde;
phys_ram_seg_t *mc;
- size_t nL4e, nL3e, pn, npd;
+ size_t nL4e, nL3e, nL2e;
+ size_t pn, npd;
int i, n;
const pd_entry_t pteflags = PG_V | PG_KW | pmap_pg_nx;
@@ -1503,6 +1504,9 @@ pmap_init_directmap(struct pmap *kpm)
/* Allocate L2. */
L2page_pa = pmap_bootstrap_palloc(nL3e);
+ /* Number of L2 entries. */
+ nL2e = (lastpa + NBPD_L2 - 1) >> L2_SHIFT;
+
KASSERT(pmap_largepages != 0);
/* Large pages are supported. Just create L2. */
@@ -1514,7 +1518,8 @@ pmap_init_directmap(struct pmap *kpm)
memset((void *)tmpva, 0, PAGE_SIZE);
pde = (pd_entry_t *)tmpva;
- for (n = 0; n < NPDPG; n++) {
+ npd = (i == nL3e - 1) ? (nL2e % NPDPG) : NPDPG;
+ for (n = 0; n < npd; n++) {
pn = (i * NPDPG) + n;
pde[n] = ((paddr_t)pn << L2_SHIFT) | pteflags |
PG_U | PG_PS | PG_G;
