From: David Daney <david.daney@xxxxxxxxxx> commit 58b69401c797 (MIPS: Function tracer: Fix broken function tracing) completely broke the function tracer for 64-bit kernels. The symptom is a system hang very early in the boot process. The fix: Remove/fix $sp adjustments for 64-bit case. Signed-off-by: David Daney <david.daney@xxxxxxxxxx> Cc: Al Cooper <alcooperx@xxxxxxxxx> Cc: viric@xxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx # 3.8.x --- arch/mips/kernel/mcount.S | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/arch/mips/kernel/mcount.S b/arch/mips/kernel/mcount.S index 1658676..33d0671 100644 --- a/arch/mips/kernel/mcount.S +++ b/arch/mips/kernel/mcount.S @@ -46,10 +46,9 @@ PTR_L a5, PT_R9(sp) PTR_L a6, PT_R10(sp) PTR_L a7, PT_R11(sp) -#else - PTR_ADDIU sp, PT_SIZE #endif -.endm + PTR_ADDIU sp, PT_SIZE + .endm .macro RETURN_BACK jr ra @@ -68,7 +67,11 @@ NESTED(ftrace_caller, PT_SIZE, ra) .globl _mcount _mcount: b ftrace_stub - addiu sp,sp,8 +#ifdef CONFIG_32BIT + addiu sp,sp,8 +#else + nop +#endif /* When tracing is activated, it calls ftrace_caller+8 (aka here) */ lw t1, function_trace_stop -- 1.7.11.7
