powerpc/64e/interrupt: Fix nvgprs being clobbered

[sfrench/cifs-2.6.git] / arch / powerpc / kernel / exceptions-64e.S

diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
index 7c3654b0d0f47b3f8a42436e59f3d3de0ca0232f..f1ae710274bc9142d5fd7fe6b4bd4f065044f734 100644 (file)
--- a/arch/powerpc/kernel/exceptions-64e.S
+++ b/arch/powerpc/kernel/exceptions-64e.S
@@ -340,6 +340,12 @@ ret_from_mc_except:
        andi.   r10,r10,IRQS_DISABLED;  /* yes -> go out of line */ \
        bne     masked_interrupt_book3e_##n
 
+/*
+ * Additional regs must be re-loaded from paca before EXCEPTION_COMMON* is
+ * called, because that does SAVE_NVGPRS which must see the original register
+ * values, otherwise the scratch values might be restored when exiting the
+ * interrupt.
+ */
 #define PROLOG_ADDITION_2REGS_GEN(n)                                       \
        std     r14,PACA_EXGEN+EX_R14(r13);                                 \
        std     r15,PACA_EXGEN+EX_R15(r13)
@@ -535,6 +541,10 @@ __end_interrupts:
                                PROLOG_ADDITION_2REGS)
        mfspr   r14,SPRN_DEAR
        mfspr   r15,SPRN_ESR
+       std     r14,_DAR(r1)
+       std     r15,_DSISR(r1)
+       ld      r14,PACA_EXGEN+EX_R14(r13)
+       ld      r15,PACA_EXGEN+EX_R15(r13)
        EXCEPTION_COMMON(0x300)
        b       storage_fault_common
 
@@ -544,6 +554,10 @@ __end_interrupts:
                                PROLOG_ADDITION_2REGS)
        li      r15,0
        mr      r14,r10
+       std     r14,_DAR(r1)
+       std     r15,_DSISR(r1)
+       ld      r14,PACA_EXGEN+EX_R14(r13)
+       ld      r15,PACA_EXGEN+EX_R15(r13)
        EXCEPTION_COMMON(0x400)
        b       storage_fault_common
 
@@ -557,6 +571,10 @@ __end_interrupts:
                                PROLOG_ADDITION_2REGS)
        mfspr   r14,SPRN_DEAR
        mfspr   r15,SPRN_ESR
+       std     r14,_DAR(r1)
+       std     r15,_DSISR(r1)
+       ld      r14,PACA_EXGEN+EX_R14(r13)
+       ld      r15,PACA_EXGEN+EX_R15(r13)
        EXCEPTION_COMMON(0x600)
        b       alignment_more  /* no room, go out of line */
 
@@ -565,10 +583,10 @@ __end_interrupts:
        NORMAL_EXCEPTION_PROLOG(0x700, BOOKE_INTERRUPT_PROGRAM,
                                PROLOG_ADDITION_1REG)
        mfspr   r14,SPRN_ESR
-       EXCEPTION_COMMON(0x700)
        std     r14,_DSISR(r1)
-       addi    r3,r1,STACK_FRAME_OVERHEAD
        ld      r14,PACA_EXGEN+EX_R14(r13)
+       EXCEPTION_COMMON(0x700)
+       addi    r3,r1,STACK_FRAME_OVERHEAD
        bl      program_check_exception
        REST_NVGPRS(r1)
        b       interrupt_return
@@ -725,11 +743,11 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
         * normal exception
         */
        mfspr   r14,SPRN_DBSR
-       EXCEPTION_COMMON_CRIT(0xd00)
        std     r14,_DSISR(r1)
-       addi    r3,r1,STACK_FRAME_OVERHEAD
        ld      r14,PACA_EXCRIT+EX_R14(r13)
        ld      r15,PACA_EXCRIT+EX_R15(r13)
+       EXCEPTION_COMMON_CRIT(0xd00)
+       addi    r3,r1,STACK_FRAME_OVERHEAD
        bl      DebugException
        REST_NVGPRS(r1)
        b       interrupt_return
@@ -796,11 +814,11 @@ kernel_dbg_exc:
         * normal exception
         */
        mfspr   r14,SPRN_DBSR
-       EXCEPTION_COMMON_DBG(0xd08)
        std     r14,_DSISR(r1)
-       addi    r3,r1,STACK_FRAME_OVERHEAD
        ld      r14,PACA_EXDBG+EX_R14(r13)
        ld      r15,PACA_EXDBG+EX_R15(r13)
+       EXCEPTION_COMMON_DBG(0xd08)
+       addi    r3,r1,STACK_FRAME_OVERHEAD
        bl      DebugException
        REST_NVGPRS(r1)
        b       interrupt_return
@@ -931,11 +949,7 @@ masked_interrupt_book3e_0x2c0:
  * original values stashed away in the PACA
  */
 storage_fault_common:
-       std     r14,_DAR(r1)
-       std     r15,_DSISR(r1)
        addi    r3,r1,STACK_FRAME_OVERHEAD
-       ld      r14,PACA_EXGEN+EX_R14(r13)
-       ld      r15,PACA_EXGEN+EX_R15(r13)
        bl      do_page_fault
        b       interrupt_return
 
@@ -944,11 +958,7 @@ storage_fault_common:
  * continues here.
  */
 alignment_more:
-       std     r14,_DAR(r1)
-       std     r15,_DSISR(r1)
        addi    r3,r1,STACK_FRAME_OVERHEAD
-       ld      r14,PACA_EXGEN+EX_R14(r13)
-       ld      r15,PACA_EXGEN+EX_R15(r13)
        bl      alignment_exception
        REST_NVGPRS(r1)
        b       interrupt_return