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authoralc <alc@FreeBSD.org>2003-12-22 02:04:08 +0000
committeralc <alc@FreeBSD.org>2003-12-22 02:04:08 +0000
commitdbc67551d35dfdec68a4408dde210754e6b1a2f3 (patch)
tree9143bacb515682b4274ad6bed7255ccfee2e1b13 /sys
parenteae1da31eade2f857fee00c87d25f65464147206 (diff)
downloadFreeBSD-src-dbc67551d35dfdec68a4408dde210754e6b1a2f3.zip
FreeBSD-src-dbc67551d35dfdec68a4408dde210754e6b1a2f3.tar.gz
- Create an unmapped guard page to trap access to vm_page_array[-1].
This guard page would have trapped the problems with the MFC of the PAE support to RELENG_4 at an earlier point in the sequence of events. Submitted by: tegge
Diffstat (limited to 'sys')
-rw-r--r--sys/vm/vm_page.c5
1 files changed, 5 insertions, 0 deletions
diff --git a/sys/vm/vm_page.c b/sys/vm/vm_page.c
index 4015593..9290a6a 100644
--- a/sys/vm/vm_page.c
+++ b/sys/vm/vm_page.c
@@ -242,6 +242,11 @@ vm_page_startup(vm_offset_t starta, vm_offset_t enda, vm_offset_t vaddr)
end = new_end;
/*
+ * Reserve an unmapped guard page to trap access to vm_page_array[-1].
+ */
+ vaddr += PAGE_SIZE;
+
+ /*
* Initialize the mem entry structures now, and put them in the free
* queue.
*/
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