powerpc: Document register clobbering in EXCEPTION_COMMON()
authorMichael Ellerman <mpe@ellerman.id.au>
Tue, 15 Jul 2014 11:15:37 +0000 (21:15 +1000)
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>
Mon, 28 Jul 2014 04:11:24 +0000 (14:11 +1000)
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
arch/powerpc/include/asm/exception-64s.h

index 8f35cd7..066c15c 100644 (file)
@@ -532,6 +532,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_CTRL)
        .globl label##_common;                                  \
 label##_common:                                                        \
        EXCEPTION_PROLOG_COMMON(trap, PACA_EXGEN);              \
+       /* Volatile regs are potentially clobbered here */      \
        additions;                                              \
        addi    r3,r1,STACK_FRAME_OVERHEAD;                     \
        bl      hdlr;                                           \