1 // SPDX-License-Identifier: GPL-2.0-only
22  * The unwind will begin at the PC within the regs.
31 	state->fp = regs->regs[29];  in unwind_init_from_regs()
32 	state->pc = regs->pc;  in unwind_init_from_regs()
47 	state->fp = (unsigned long)__builtin_frame_address(1);  in unwind_init_from_caller()
48 	state->pc = (unsigned long)__builtin_return_address(0);  in unwind_init_from_caller()
54  * The unwind will begin at the blocked tasks saved PC (i.e. the caller of
66 	state->fp = thread_saved_fp(task);  in unwind_init_from_task()
67 	state->pc = thread_saved_pc(task);  in unwind_init_from_task()
79 	struct task_struct *tsk = state->task;  in unwind_next()
80 	unsigned long fp = state->fp;  in unwind_next()
84 	if (fp == (unsigned long)task_pt_regs(tsk)->stackframe)  in unwind_next()
85 		return -ENOENT;  in unwind_next()
91 	state->pc = ptrauth_strip_insn_pac(state->pc);  in unwind_next()
94 	if (tsk->ret_stack &&  in unwind_next()
95 		(state->pc == (unsigned long)return_to_handler)) {  in unwind_next()
103 		orig_pc = ftrace_graph_ret_addr(tsk, NULL, state->pc,  in unwind_next()
104 						(void *)state->fp);  in unwind_next()
105 		if (WARN_ON_ONCE(state->pc == orig_pc))  in unwind_next()
106 			return -EINVAL;  in unwind_next()
107 		state->pc = orig_pc;  in unwind_next()
111 	if (is_kretprobe_trampoline(state->pc))  in unwind_next()
112 		state->pc = kretprobe_find_ret_addr(tsk, (void *)state->fp, &state->kr_cur);  in unwind_next()
125 		if (!consume_entry(cookie, state->pc))  in unwind()
168  * Per-cpu stacks are only accessible when unwinding the current task in a
169  * non-preemptible context.