[src/trunk]: src/sys/uvm in uvm_fault_unwire_locked(), if we find that a pmap...

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

details:   https://anonhg.NetBSD.org/src/rev/cd26aac43f81
branches:  trunk
changeset: 520049:cd26aac43f81
user:      chs <chs%NetBSD.org@localhost>
date:      Wed Jan 02 01:10:36 2002 +0000

description:
in uvm_fault_unwire_locked(), if we find that a pmap entry is missing,
just skip that page.  this situation can arise legitimately when a file
with a wired mapping is truncated so that a wired page is no longer
part of the file.

diffstat:

 sys/uvm/uvm_fault.c |  14 +++++++-------
 1 files changed, 7 insertions(+), 7 deletions(-)

diffs (53 lines):

diff -r e5ae0e3095f0 -r cd26aac43f81 sys/uvm/uvm_fault.c
--- a/sys/uvm/uvm_fault.c       Wed Jan 02 00:51:33 2002 +0000
+++ b/sys/uvm/uvm_fault.c       Wed Jan 02 01:10:36 2002 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: uvm_fault.c,v 1.73 2002/01/01 22:18:39 chs Exp $       */
+/*     $NetBSD: uvm_fault.c,v 1.74 2002/01/02 01:10:36 chs Exp $       */
 
 /*
  *
@@ -39,7 +39,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uvm_fault.c,v 1.73 2002/01/01 22:18:39 chs Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uvm_fault.c,v 1.74 2002/01/02 01:10:36 chs Exp $");
 
 #include "opt_uvmhist.h"
 
@@ -1800,22 +1800,21 @@
        /*
         * find the beginning map entry for the region.
         */
+
        KASSERT(start >= vm_map_min(map) && end <= vm_map_max(map));
        if (uvm_map_lookup_entry(map, start, &entry) == FALSE)
                panic("uvm_fault_unwire_locked: address not in map");
 
        for (va = start; va < end; va += PAGE_SIZE) {
                if (pmap_extract(pmap, va, &pa) == FALSE)
-                       panic("uvm_fault_unwire_locked: unwiring "
-                           "non-wired memory");
+                       continue;
 
                /*
-                * make sure the current entry is for the address we're
-                * dealing with.  if not, grab the next entry.
+                * find the map entry for the current address.
                 */
 
                KASSERT(va >= entry->start);
-               if (va >= entry->end) {
+               while (va >= entry->end) {
                        KASSERT(entry->next != &map->header &&
                                entry->next->start <= entry->end);
                        entry = entry->next;
@@ -1824,6 +1823,7 @@
                /*
                 * if the entry is no longer wired, tell the pmap.
                 */
+
                if (VM_MAPENT_ISWIRED(entry) == 0)
                        pmap_unwire(pmap, va);