[PATCH] x86_64: Adjust page fault handling
Adjust page fault protection error check before considering it to be
a vmalloc synchronization candidate.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/x86_64/mm/fault.c b/arch/x86_64/mm/fault.c
index 21d1596..fd07b86 100644
--- a/arch/x86_64/mm/fault.c
+++ b/arch/x86_64/mm/fault.c
@@ -299,7 +299,8 @@
* bit 0 == 0 means no page found, 1 means protection fault
* bit 1 == 0 means read, 1 means write
* bit 2 == 0 means kernel, 1 means user-mode
- * bit 3 == 1 means fault was an instruction fetch
+ * bit 3 == 1 means use of reserved bit detected
+ * bit 4 == 1 means fault was an instruction fetch
*/
asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
unsigned long error_code)
@@ -342,10 +343,10 @@
*
* This verifies that the fault happens in kernel space
* (error_code & 4) == 0, and that the fault was not a
- * protection error (error_code & 1) == 0.
+ * protection error (error_code & 9) == 0.
*/
if (unlikely(address >= TASK_SIZE64)) {
- if (!(error_code & 5) &&
+ if (!(error_code & 0xd) &&
((address >= VMALLOC_START && address < VMALLOC_END) ||
(address >= MODULES_VADDR && address < MODULES_END))) {
if (vmalloc_fault(address) < 0)