Commit bc8d7521 authored by Mark Rutland's avatar Mark Rutland Committed by Catalin Marinas
Browse files

arm64: stacktrace: simplify unwind_next_common() 



Currently unwind_next_common() takes a pointer to a stack_info which is
only ever used within unwind_next_common().

Make it a local variable and simplify callers.

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

Signed-off-by: default avatarMark Rutland <mark.rutland@arm.com>
Reviewed-by: default avatarKalesh Singh <kaleshsingh@google.com>
Reviewed-by: default avatarMadhavan T. Venkataraman <madvenka@linux.microsoft.com>
Reviewed-by: default avatarMark Brown <broonie@kernel.org>
Cc: Fuad Tabba <tabba@google.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20220901130646.1316937-3-mark.rutland@arm.com


Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent 16283c54

arch/arm64/include/asm/stacktrace/common.h

+6 −6
Original line number Diff line number Diff line
@@ -146,27 +146,27 @@ typedef bool (*on_accessible_stack_fn)(const struct task_struct *tsk, 
				       struct stack_info *info);



static inline int unwind_next_common(struct unwind_state *state,

				     struct stack_info *info,

				     on_accessible_stack_fn accessible,

				     stack_trace_translate_fp_fn translate_fp)

{

	struct stack_info info;

	unsigned long fp = state->fp, kern_fp = fp;

	struct task_struct *tsk = state->task;



	if (fp & 0x7)

		return -EINVAL;



	if (!accessible(tsk, fp, 16, info))

	if (!accessible(tsk, fp, 16, &info))

		return -EINVAL;



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

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

		return -EINVAL;



	/*

	 * If fp is not from the current address space perform the necessary

	 * translation before dereferencing it to get the next fp.

	 */

	if (translate_fp && !translate_fp(&kern_fp, info->type))

	if (translate_fp && !translate_fp(&kern_fp, info.type))

		return -EINVAL;



	/*
@@ -183,7 +183,7 @@ static inline int unwind_next_common(struct unwind_state *state, 
	 * stack to another, it's never valid to unwind back to that first

	 * stack.

	 */

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

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

		if (fp <= state->prev_fp)

			return -EINVAL;

	} else {
@@ -197,7 +197,7 @@ static inline int unwind_next_common(struct unwind_state *state, 
	state->fp = READ_ONCE(*(unsigned long *)(kern_fp));

	state->pc = READ_ONCE(*(unsigned long *)(kern_fp + 8));

	state->prev_fp = fp;

	state->prev_type = info->type;

	state->prev_type = info.type;



	return 0;

}

arch/arm64/kernel/stacktrace.c

+1 −2
Original line number Diff line number Diff line
@@ -103,14 +103,13 @@ static int notrace unwind_next(struct unwind_state *state) 
{

	struct task_struct *tsk = state->task;

	unsigned long fp = state->fp;

	struct stack_info info;

	int err;



	/* Final frame; nothing to unwind */

	if (fp == (unsigned long)task_pt_regs(tsk)->stackframe)

		return -ENOENT;



	err = unwind_next_common(state, &info, on_accessible_stack, NULL);

	err = unwind_next_common(state, on_accessible_stack, NULL);

	if (err)

		return err;

arch/arm64/kvm/hyp/nvhe/stacktrace.c

+1 −3
Original line number Diff line number Diff line
@@ -71,9 +71,7 @@ static bool on_accessible_stack(const struct task_struct *tsk, 


static int unwind_next(struct unwind_state *state)

{

	struct stack_info info;



	return unwind_next_common(state, &info, on_accessible_stack, NULL);

	return unwind_next_common(state, on_accessible_stack, NULL);

}



static void notrace unwind(struct unwind_state *state,

arch/arm64/kvm/stacktrace.c

+1 −3
Original line number Diff line number Diff line
@@ -97,9 +97,7 @@ static bool on_accessible_stack(const struct task_struct *tsk, 


static int unwind_next(struct unwind_state *state)

{

	struct stack_info info;



	return unwind_next_common(state, &info, on_accessible_stack,

	return unwind_next_common(state, on_accessible_stack,

				  kvm_nvhe_stack_kern_va);

}