linux/arch/loongarch/kernel/unwind.c
Jinyang He 97ceddbc94 LoongArch: Set unwind stack type to unknown rather than set error flag
During unwinding, unwind_done() is used as an end condition. Normally it
unwind to the user stack and then set the stack type to unknown, which
is a normal exit. When something unexpected happens in unwind process
and we cannot unwind anymore, we should set the error flag, and also set
the stack type to unknown to indicate that the unwind process can not
continue. The error flag emphasizes that the unwind process produce an
unexpected error. There is no unexpected things when we unwind the PT_REGS
in the top of IRQ stack and find out that is an user mode PT_REGS. Thus,
we should not set error flag and just set stack type to unknown.

Reported-by: Hengqi Chen <hengqi.chen@gmail.com>
Acked-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-12-09 15:49:15 +08:00

33 lines
742 B
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2022-2023 Loongson Technology Corporation Limited
*/
#include <linux/kernel.h>
#include <linux/ftrace.h>
#include <asm/unwind.h>
bool default_next_frame(struct unwind_state *state)
{
struct stack_info *info = &state->stack_info;
unsigned long addr;
if (unwind_done(state))
return false;
do {
for (state->sp += sizeof(unsigned long);
state->sp < info->end; state->sp += sizeof(unsigned long)) {
addr = *(unsigned long *)(state->sp);
state->pc = unwind_graph_addr(state, addr, state->sp + 8);
if (__kernel_text_address(state->pc))
return true;
}
state->sp = info->next_sp;
} while (!get_stack_info(state->sp, state->task, info));
return false;
}