From 2a7d90df161795978d324a8356264dc7971d5385 Mon Sep 17 00:00:00 2001
From: Shaohua Li <shaohua.li@intel.com>
Date: Tue, 27 Jul 2010 16:06:28 +0800
Subject: [PATCH] --- yaml --- r: 212059 b: refs/heads/master c:
 660a293ea9be709b893d371fbc0328fcca33c33a h: refs/heads/master i:   212057:
 8d6ffaad9a1c0c2a22ddcfa554ee1675a0ddc6e0   212055:
 7322e17090c54407188b5da10486e3ab232c9d83 v: v3

---
 [refs]                    | 2 +-
 trunk/arch/x86/mm/fault.c | 8 +++++++-
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index 054e041392f5..959a1dff11bb 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 9b861528a8012e7bc4d1f7bae07395b225331477
+refs/heads/master: 660a293ea9be709b893d371fbc0328fcca33c33a
diff --git a/trunk/arch/x86/mm/fault.c b/trunk/arch/x86/mm/fault.c
index 51f7ee71d6c7..caec22906d7c 100644
--- a/trunk/arch/x86/mm/fault.c
+++ b/trunk/arch/x86/mm/fault.c
@@ -872,8 +872,14 @@ spurious_fault(unsigned long error_code, unsigned long address)
 	if (pmd_large(*pmd))
 		return spurious_fault_check(error_code, (pte_t *) pmd);
 
+	/*
+	 * Note: don't use pte_present() here, since it returns true
+	 * if the _PAGE_PROTNONE bit is set.  However, this aliases the
+	 * _PAGE_GLOBAL bit, which for kernel pages give false positives
+	 * when CONFIG_DEBUG_PAGEALLOC is used.
+	 */
 	pte = pte_offset_kernel(pmd, address);
-	if (!pte_present(*pte))
+	if (!(pte_flags(*pte) & _PAGE_PRESENT))
 		return 0;
 
 	ret = spurious_fault_check(error_code, pte);