diff options
Diffstat (limited to 'arch/arm/kernel/ftrace.c')
| -rw-r--r-- | arch/arm/kernel/ftrace.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/arch/arm/kernel/ftrace.c b/arch/arm/kernel/ftrace.c index ea2396900c7d..83cc068586bc 100644 --- a/arch/arm/kernel/ftrace.c +++ b/arch/arm/kernel/ftrace.c @@ -22,6 +22,7 @@ #include <asm/ftrace.h> #include <asm/insn.h> #include <asm/set_memory.h> +#include <asm/stacktrace.h> #include <asm/patch.h> /* @@ -224,8 +225,10 @@ int ftrace_make_nop(struct module *mod, #endif /* CONFIG_DYNAMIC_FTRACE */ #ifdef CONFIG_FUNCTION_GRAPH_TRACER +asmlinkage void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr, - unsigned long frame_pointer) + unsigned long frame_pointer, + unsigned long stack_pointer) { unsigned long return_hooker = (unsigned long) &return_to_handler; unsigned long old; @@ -236,6 +239,18 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr, if (IS_ENABLED(CONFIG_UNWINDER_FRAME_POINTER)) { /* FP points one word below parent's top of stack */ frame_pointer += 4; + } else { + struct stackframe frame = { + .fp = frame_pointer, + .sp = stack_pointer, + .lr = self_addr, + .pc = self_addr, + }; + if (unwind_frame(&frame) < 0) + return; + if (frame.lr != self_addr) + parent = frame.lr_addr; + frame_pointer = frame.sp; } old = *parent; @@ -258,7 +273,7 @@ static int __ftrace_modify_caller(unsigned long *callsite, unsigned long caller_fn = (unsigned long) func; unsigned long pc = (unsigned long) callsite; unsigned long branch = arm_gen_branch(pc, caller_fn); - unsigned long nop = 0xe1a00000; /* mov r0, r0 */ + unsigned long nop = arm_gen_nop(); unsigned long old = enable ? nop : branch; unsigned long new = enable ? branch : nop; |