arch/x86/kernel/stacktrace.c

Source file repositories/reference/linux-study-clean/arch/x86/kernel/stacktrace.c

File Facts

System
Linux kernel
Corpus path
arch/x86/kernel/stacktrace.c
Extension
.c
Size
2924 bytes
Lines
131
Domain
Architecture Layer
Bucket
arch/x86
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

struct stack_frame_user {
	const void __user	*next_fp;
	unsigned long		ret_addr;
};

static int
copy_stack_frame(const struct stack_frame_user __user *fp,
		 struct stack_frame_user *frame)
{
	int ret;

	if (!__access_ok(fp, sizeof(*frame)))
		return 0;

	ret = 1;
	pagefault_disable();
	if (__get_user(frame->next_fp, &fp->next_fp) ||
	    __get_user(frame->ret_addr, &fp->ret_addr))
		ret = 0;
	pagefault_enable();

	return ret;
}

void arch_stack_walk_user(stack_trace_consume_fn consume_entry, void *cookie,
			  const struct pt_regs *regs)
{
	const void __user *fp = (const void __user *)regs->bp;

	if (!consume_entry(cookie, regs->ip))
		return;

	while (1) {
		struct stack_frame_user frame;

		frame.next_fp = NULL;
		frame.ret_addr = 0;
		if (!copy_stack_frame(fp, &frame))
			break;
		if ((unsigned long)fp < regs->sp)
			break;
		if (!frame.ret_addr)
			break;
		if (!consume_entry(cookie, frame.ret_addr))
			break;
		fp = frame.next_fp;
	}
}

Annotation

Implementation Notes