1 // SPDX-License-Identifier: GPL-2.0
3 * Stack trace management functions
5 * Copyright (C) 2022 Loongson Technology Corporation Limited
7 #include <linux/sched.h>
8 #include <linux/stacktrace.h>
9 #include <linux/uaccess.h>
11 #include <asm/stacktrace.h>
12 #include <asm/unwind.h>
14 void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie,
15 struct task_struct *task, struct pt_regs *regs)
18 struct pt_regs dummyregs;
19 struct unwind_state state;
23 if (task == current) {
24 regs->regs[3] = (unsigned long)__builtin_frame_address(0);
25 regs->csr_era = (unsigned long)__builtin_return_address(0);
27 regs->regs[3] = thread_saved_fp(task);
28 regs->csr_era = thread_saved_ra(task);
32 for (unwind_start(&state, task, regs);
33 !unwind_done(&state); unwind_next_frame(&state)) {
34 addr = unwind_get_return_address(&state);
35 if (!addr || !consume_entry(cookie, addr))
41 copy_stack_frame(unsigned long fp, struct stack_frame *frame)
45 unsigned long __user *user_frame_tail;
47 user_frame_tail = (unsigned long *)(fp - sizeof(struct stack_frame));
48 if (!access_ok(user_frame_tail, sizeof(*frame)))
52 err = (__copy_from_user_inatomic(frame, user_frame_tail, sizeof(*frame)));
53 if (err || (unsigned long)user_frame_tail >= frame->fp)
60 void arch_stack_walk_user(stack_trace_consume_fn consume_entry, void *cookie,
61 const struct pt_regs *regs)
63 unsigned long fp = regs->regs[22];
65 while (fp && !((unsigned long)fp & 0xf)) {
66 struct stack_frame frame;
70 if (!copy_stack_frame(fp, &frame))
74 if (!consume_entry(cookie, frame.ra))