Commit e9d75a0b authored by Madhavan T. Venkataraman's avatar Madhavan T. Venkataraman Committed by Catalin Marinas
Browse files

arm64: stacktrace: rename stackframe to unwind_state 



Rename "struct stackframe" to "struct unwind_state" for consistency and
better naming. Accordingly, rename variable/argument "frame" to "state".

There should be no functional change as a result of this patch.

Signed-off-by: default avatarMadhavan T. Venkataraman <madvenka@linux.microsoft.com>
Reviewed-by: default avatarMark Brown <broonie@kernel.org>
Signed-off-by: default avatarMark Rutland <mark.rutland@arm.com>
Reviewed-by: Kalesh Singh <kaleshsingh@google.com> for the series.
Link: https://lore.kernel.org/r/20220413145910.3060139-6-mark.rutland@arm.com


Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent c797bd45

arch/arm64/kernel/stacktrace.c

+34 −34
Original line number Diff line number Diff line
@@ -39,7 +39,7 @@ 
 *               associated with the most recently encountered replacement lr

 *               value.

 */

struct stackframe {

struct unwind_state {

	unsigned long fp;

	unsigned long pc;

	DECLARE_BITMAP(stacks_done, __NR_STACK_TYPES);
@@ -50,13 +50,13 @@ struct stackframe { 
#endif

};



static notrace void unwind_init(struct stackframe *frame, unsigned long fp,

static notrace void unwind_init(struct unwind_state *state, unsigned long fp,

				unsigned long pc)

{

	frame->fp = fp;

	frame->pc = pc;

	state->fp = fp;

	state->pc = pc;

#ifdef CONFIG_KRETPROBES

	frame->kr_cur = NULL;

	state->kr_cur = NULL;

#endif



	/*
@@ -68,9 +68,9 @@ static notrace void unwind_init(struct stackframe *frame, unsigned long fp, 
	 * prev_fp value won't be used, but we set it to 0 such that it is

	 * definitely not an accessible stack address.

	 */

	bitmap_zero(frame->stacks_done, __NR_STACK_TYPES);

	frame->prev_fp = 0;

	frame->prev_type = STACK_TYPE_UNKNOWN;

	bitmap_zero(state->stacks_done, __NR_STACK_TYPES);

	state->prev_fp = 0;

	state->prev_type = STACK_TYPE_UNKNOWN;

}

NOKPROBE_SYMBOL(unwind_init);
@@ -82,9 +82,9 @@ NOKPROBE_SYMBOL(unwind_init); 
 * and the location (but not the fp value) of B.

 */

static int notrace unwind_next(struct task_struct *tsk,

			       struct stackframe *frame)

			       struct unwind_state *state)

{

	unsigned long fp = frame->fp;

	unsigned long fp = state->fp;

	struct stack_info info;



	/* Final frame; nothing to unwind */
@@ -97,7 +97,7 @@ static int notrace unwind_next(struct task_struct *tsk, 
	if (!on_accessible_stack(tsk, fp, 16, &info))

		return -EINVAL;



	if (test_bit(info.type, frame->stacks_done))

	if (test_bit(info.type, state->stacks_done))

		return -EINVAL;



	/*
@@ -113,27 +113,27 @@ static int notrace unwind_next(struct task_struct *tsk, 
	 * stack to another, it's never valid to unwind back to that first

	 * stack.

	 */

	if (info.type == frame->prev_type) {

		if (fp <= frame->prev_fp)

	if (info.type == state->prev_type) {

		if (fp <= state->prev_fp)

			return -EINVAL;

	} else {

		set_bit(frame->prev_type, frame->stacks_done);

		set_bit(state->prev_type, state->stacks_done);

	}



	/*

	 * Record this frame record's values and location. The prev_fp and

	 * prev_type are only meaningful to the next unwind_next() invocation.

	 */

	frame->fp = READ_ONCE_NOCHECK(*(unsigned long *)(fp));

	frame->pc = READ_ONCE_NOCHECK(*(unsigned long *)(fp + 8));

	frame->prev_fp = fp;

	frame->prev_type = info.type;

	state->fp = READ_ONCE_NOCHECK(*(unsigned long *)(fp));

	state->pc = READ_ONCE_NOCHECK(*(unsigned long *)(fp + 8));

	state->prev_fp = fp;

	state->prev_type = info.type;



	frame->pc = ptrauth_strip_insn_pac(frame->pc);

	state->pc = ptrauth_strip_insn_pac(state->pc);



#ifdef CONFIG_FUNCTION_GRAPH_TRACER

	if (tsk->ret_stack &&

		(frame->pc == (unsigned long)return_to_handler)) {

		(state->pc == (unsigned long)return_to_handler)) {

		unsigned long orig_pc;

		/*

		 * This is a case where function graph tracer has
@@ -141,16 +141,16 @@ static int notrace unwind_next(struct task_struct *tsk, 
		 * to hook a function return.

		 * So replace it to an original value.

		 */

		orig_pc = ftrace_graph_ret_addr(tsk, NULL, frame->pc,

						(void *)frame->fp);

		if (WARN_ON_ONCE(frame->pc == orig_pc))

		orig_pc = ftrace_graph_ret_addr(tsk, NULL, state->pc,

						(void *)state->fp);

		if (WARN_ON_ONCE(state->pc == orig_pc))

			return -EINVAL;

		frame->pc = orig_pc;

		state->pc = orig_pc;

	}

#endif /* CONFIG_FUNCTION_GRAPH_TRACER */

#ifdef CONFIG_KRETPROBES

	if (is_kretprobe_trampoline(frame->pc))

		frame->pc = kretprobe_find_ret_addr(tsk, (void *)frame->fp, &frame->kr_cur);

	if (is_kretprobe_trampoline(state->pc))

		state->pc = kretprobe_find_ret_addr(tsk, (void *)state->fp, &state->kr_cur);

#endif



	return 0;
@@ -158,15 +158,15 @@ static int notrace unwind_next(struct task_struct *tsk, 
NOKPROBE_SYMBOL(unwind_next);



static void notrace unwind(struct task_struct *tsk,

			   struct stackframe *frame,

			   struct unwind_state *state,

			   bool (*fn)(void *, unsigned long), void *data)

{

	while (1) {

		int ret;



		if (!fn(data, frame->pc))

		if (!fn(data, state->pc))

			break;

		ret = unwind_next(tsk, frame);

		ret = unwind_next(tsk, state);

		if (ret < 0)

			break;

	}
@@ -210,17 +210,17 @@ noinline notrace void arch_stack_walk(stack_trace_consume_fn consume_entry, 
			      void *cookie, struct task_struct *task,

			      struct pt_regs *regs)

{

	struct stackframe frame;

	struct unwind_state state;



	if (regs)

		unwind_init(&frame, regs->regs[29], regs->pc);

		unwind_init(&state, regs->regs[29], regs->pc);

	else if (task == current)

		unwind_init(&frame,

		unwind_init(&state,

				(unsigned long)__builtin_frame_address(1),

				(unsigned long)__builtin_return_address(0));

	else

		unwind_init(&frame, thread_saved_fp(task),

		unwind_init(&state, thread_saved_fp(task),

				thread_saved_pc(task));



	unwind(task, &frame, consume_entry, cookie);

	unwind(task, &state, consume_entry, cookie);

}