[PATCH] ppc32: fix CONFIG_TASK_SIZE handling on 40x

[Eugene Surovegin]

Hi!

This patch is virtually identical to my previous 44x one. It removes 
0x8000'0000 TASK_SIZE hardcoded assumption from head_4xx.S.

I don't have any 40x board which runs 2.6, so this one is untested, 
bit it compiles :).

Signed-off-by: Eugene Surovegin <ebs at ebshome.net>

Index: arch/ppc/kernel/head_4xx.S
===================================================================
--- 59c3218467807e1793fb4fc5d90141e072ab2212/arch/ppc/kernel/head_4xx.S  (mode:100644)
+++ uncommitted/arch/ppc/kernel/head_4xx.S  (mode:100644)
@@ -291,8 +291,9 @@
 	/* If we are faulting a kernel address, we have to use the
 	 * kernel page tables.
 	 */
-	andis.	r11, r10, 0x8000
-	beq	3f
+	lis	r11, TASK_SIZE at h 
+	cmplw	r10, r11
+	blt+	3f
 	lis	r11, swapper_pg_dir at h
 	ori	r11, r11, swapper_pg_dir at l
 	li	r9, 0
@@ -479,8 +480,9 @@
 	/* If we are faulting a kernel address, we have to use the
 	 * kernel page tables.
 	 */
-	andis.	r11, r10, 0x8000
-	beq	3f
+	lis	r11, TASK_SIZE at h 
+	cmplw	r10, r11
+	blt+	3f
 	lis	r11, swapper_pg_dir at h
 	ori	r11, r11, swapper_pg_dir at l
 	li	r9, 0
@@ -578,8 +580,9 @@
 	/* If we are faulting a kernel address, we have to use the
 	 * kernel page tables.
 	 */
-	andis.	r11, r10, 0x8000
-	beq	3f
+	lis	r11, TASK_SIZE at h 
+	cmplw	r10, r11
+	blt+	3f
 	lis	r11, swapper_pg_dir at h
 	ori	r11, r11, swapper_pg_dir at l
 	li	r9, 0