Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/g…

…it/aegl/linux-2.6 * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6: [IA64] Fix race in the accessed/dirty bit handlers
git-mirror · Mar 11, 2006 · 35ab0e8 · 35ab0e8
2 parents 44f329a + d8117ce
commit 35ab0e8
Showing 1 changed file with 9 additions and 6 deletions.
diff --git a/arch/ia64/kernel/ivt.S b/arch/ia64/kernel/ivt.S
@@ -561,11 +561,12 @@ ENTRY(dirty_bit)
 	;;					// avoid RAW on r18
 	mov ar.ccv=r18				// set compare value for cmpxchg
 	or r25=_PAGE_D|_PAGE_A,r18		// set the dirty and accessed bits
+	tbit.z p7,p6 = r18,_PAGE_P_BIT		// Check present bit
 	;;
-	cmpxchg8.acq r26=[r17],r25,ar.ccv
+(p6)	cmpxchg8.acq r26=[r17],r25,ar.ccv	// Only update if page is present
 	mov r24=PAGE_SHIFT<<2
 	;;
-	cmp.eq p6,p7=r26,r18
+(p6)	cmp.eq p6,p7=r26,r18			// Only compare if page is present
 	;;
 (p6)	itc.d r25				// install updated PTE
 	;;
@@ -626,11 +627,12 @@ ENTRY(iaccess_bit)
 	;;
 	mov ar.ccv=r18				// set compare value for cmpxchg
 	or r25=_PAGE_A,r18			// set the accessed bit
+	tbit.z p7,p6 = r18,_PAGE_P_BIT	 	// Check present bit
 	;;
-	cmpxchg8.acq r26=[r17],r25,ar.ccv
+(p6)	cmpxchg8.acq r26=[r17],r25,ar.ccv	// Only if page present
 	mov r24=PAGE_SHIFT<<2
 	;;
-	cmp.eq p6,p7=r26,r18
+(p6)	cmp.eq p6,p7=r26,r18			// Only if page present
 	;;
 (p6)	itc.i r25				// install updated PTE
 	;;
@@ -680,11 +682,12 @@ ENTRY(daccess_bit)
 	;;					// avoid RAW on r18
 	mov ar.ccv=r18				// set compare value for cmpxchg
 	or r25=_PAGE_A,r18			// set the dirty bit
+	tbit.z p7,p6 = r18,_PAGE_P_BIT		// Check present bit
 	;;
-	cmpxchg8.acq r26=[r17],r25,ar.ccv
+(p6)	cmpxchg8.acq r26=[r17],r25,ar.ccv	// Only if page is present
 	mov r24=PAGE_SHIFT<<2
 	;;
-	cmp.eq p6,p7=r26,r18
+(p6)	cmp.eq p6,p7=r26,r18			// Only if page is present
 	;;
 (p6)	itc.d r25				// install updated PTE
 	/*