microblaze: Fix stack usage in interrupt handler

Do not save registers below r1 stack pointer because
it is not checked by stack undeflow is not able to detect
it.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>

diff --git a/arch/microblaze/cpu/irq.S b/arch/microblaze/cpu/irq.S
index 24015898b0aa172f798f3468781abf55b7311499..5cfe1516bfcd65fd82f8843b2271ada36990add8 100644 (file)
--- a/arch/microblaze/cpu/irq.S
+++ b/arch/microblaze/cpu/irq.S
@@ -11,71 +11,70 @@
        .text
        .global _interrupt_handler
 _interrupt_handler:
-       swi     r2, r1, -4
-       swi     r3, r1, -8
-       swi     r4, r1, -12
-       swi     r5, r1, -16
-       swi     r6, r1, -20
-       swi     r7, r1, -24
-       swi     r8, r1, -28
-       swi     r9, r1, -32
-       swi     r10, r1, -36
-       swi     r11, r1, -40
-       swi     r12, r1, -44
-       swi     r13, r1, -48
-       swi     r14, r1, -52
-       swi     r15, r1, -56
-       swi     r16, r1, -60
-       swi     r17, r1, -64
-       swi     r18, r1, -68
-       swi     r19, r1, -72
-       swi     r20, r1, -76
-       swi     r21, r1, -80
-       swi     r22, r1, -84
-       swi     r23, r1, -88
-       swi     r24, r1, -92
-       swi     r25, r1, -96
-       swi     r26, r1, -100
-       swi     r27, r1, -104
-       swi     r28, r1, -108
-       swi     r29, r1, -112
-       swi     r30, r1, -116
-       swi     r31, r1, -120
        addik   r1, r1, -124
+       swi     r2, r1, 4
+       swi     r3, r1, 8
+       swi     r4, r1, 12
+       swi     r5, r1, 16
+       swi     r6, r1, 20
+       swi     r7, r1, 24
+       swi     r8, r1, 28
+       swi     r9, r1, 32
+       swi     r10, r1, 36
+       swi     r11, r1, 40
+       swi     r12, r1, 44
+       swi     r13, r1, 48
+       swi     r14, r1, 52
+       swi     r15, r1, 56
+       swi     r16, r1, 60
+       swi     r17, r1, 64
+       swi     r18, r1, 68
+       swi     r19, r1, 72
+       swi     r20, r1, 76
+       swi     r21, r1, 80
+       swi     r22, r1, 84
+       swi     r23, r1, 88
+       swi     r24, r1, 92
+       swi     r25, r1, 96
+       swi     r26, r1, 100
+       swi     r27, r1, 104
+       swi     r28, r1, 108
+       swi     r29, r1, 112
+       swi     r30, r1, 116
+       swi     r31, r1, 120
        brlid   r15, interrupt_handler
        nop
+       lwi     r31, r1, 120
+       lwi     r30, r1, 116
+       lwi     r29, r1, 112
+       lwi     r28, r1, 108
+       lwi     r27, r1, 104
+       lwi     r26, r1, 100
+       lwi     r25, r1, 96
+       lwi     r24, r1, 92
+       lwi     r23, r1, 88
+       lwi     r22, r1, 84
+       lwi     r21, r1, 80
+       lwi     r20, r1, 76
+       lwi     r19, r1, 72
+       lwi     r18, r1, 68
+       lwi     r17, r1, 64
+       lwi     r16, r1, 60
+       lwi     r15, r1, 56
+       lwi     r14, r1, 52
+       lwi     r13, r1, 48
+       lwi     r12, r1, 44
+       lwi     r11, r1, 40
+       lwi     r10, r1, 36
+       lwi     r9, r1, 32
+       lwi     r8, r1, 28
+       lwi     r7, r1, 24
+       lwi     r6, r1, 20
+       lwi     r5, r1, 16
+       lwi     r4, r1, 12
+       lwi     r3, r1, 8
+       lwi     r2, r1, 4
        addik   r1, r1, 124
-       lwi     r31, r1, -120
-       lwi     r30, r1, -116
-       lwi     r29, r1, -112
-       lwi     r28, r1, -108
-       lwi     r27, r1, -104
-       lwi     r26, r1, -100
-       lwi     r25, r1, -96
-       lwi     r24, r1, -92
-       lwi     r23, r1, -88
-       lwi     r22, r1, -84
-       lwi     r21, r1, -80
-       lwi     r20, r1, -76
-       lwi     r19, r1, -72
-       lwi     r18, r1, -68
-       lwi     r17, r1, -64
-       lwi     r16, r1, -60
-       lwi     r15, r1, -56
-       lwi     r14, r1, -52
-       lwi     r13, r1, -48
-       lwi     r12, r1, -44
-       lwi     r11, r1, -40
-       lwi     r10, r1, -36
-       lwi     r9, r1, -32
-       lwi     r8, r1, -28
-       lwi     r7, r1, -24
-       lwi     r6, r1, -20
-       lwi     r5, r1, -16
-       lwi     r4, r1, -12
-       lwi     r3, r1, -8
-       lwi     r2, r1, -4
-
        rtid    r14, 0
        nop
        .size _interrupt_handler,.-_interrupt_handler