Merge remote-tracking branch 'signal/for-next'

[karo-tx-linux.git] / arch / powerpc / kernel / entry_64.S

diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 1ca3d9fa48c470b927186b044a5de1abb7d7d10e..56e0ff0878b5534c76b8c93818f7536498ce52df 100644 (file)
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -609,6 +609,41 @@ _GLOBAL(ret_from_except_lite)
        b       .ret_from_except
 
 resume_kernel:
+       /* check current_thread_info, _TIF_EMULATE_STACK_STORE */
+       CURRENT_THREAD_INFO(r9, r1)
+       ld      r8,TI_FLAGS(r9)
+       andis.  r8,r8,_TIF_EMULATE_STACK_STORE@h
+       beq+    1f
+
+       addi    r8,r1,INT_FRAME_SIZE    /* Get the kprobed function entry */
+
+       lwz     r3,GPR1(r1)
+       subi    r3,r3,INT_FRAME_SIZE    /* dst: Allocate a trampoline exception frame */
+       mr      r4,r1                   /* src:  current exception frame */
+       mr      r1,r3                   /* Reroute the trampoline frame to r1 */
+
+       /* Copy from the original to the trampoline. */
+       li      r5,INT_FRAME_SIZE/8     /* size: INT_FRAME_SIZE */
+       li      r6,0                    /* start offset: 0 */
+       mtctr   r5
+2:     ldx     r0,r6,r4
+       stdx    r0,r6,r3
+       addi    r6,r6,8
+       bdnz    2b
+
+       /* Do real store operation to complete stwu */
+       lwz     r5,GPR1(r1)
+       std     r8,0(r5)
+
+       /* Clear _TIF_EMULATE_STACK_STORE flag */
+       lis     r11,_TIF_EMULATE_STACK_STORE@h
+       addi    r5,r9,TI_FLAGS
+       ldarx   r4,0,r5
+       andc    r4,r4,r11
+       stdcx.  r4,0,r5
+       bne-    0b
+1:
+
 #ifdef CONFIG_PREEMPT
        /* Check if we need to preempt */
        andi.   r0,r4,_TIF_NEED_RESCHED