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>

diff --git a/arch/loongarch/kernel/stacktrace.c b/arch/loongarch/kernel/stacktrace.c
index 92270f1..f623feb 100644 (file)
--- a/arch/loongarch/kernel/stacktrace.c
+++ b/arch/loongarch/kernel/stacktrace.c
@@ -32,7 +32,7 @@ void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie,
        }
 
        for (unwind_start(&state, task, regs);
-            !unwind_done(&state) && !unwind_error(&state); unwind_next_frame(&state)) {
+            !unwind_done(&state); unwind_next_frame(&state)) {
                addr = unwind_get_return_address(&state);
                if (!addr || !consume_entry(cookie, addr))
                        break;

diff --git a/arch/loongarch/kernel/unwind.c b/arch/loongarch/kernel/unwind.c
index ba324ba..a463d69 100644 (file)
--- a/arch/loongarch/kernel/unwind.c
+++ b/arch/loongarch/kernel/unwind.c
@@ -28,6 +28,5 @@ bool default_next_frame(struct unwind_state *state)
 
        } while (!get_stack_info(state->sp, state->task, info));
 
-       state->error = true;
        return false;
 }

diff --git a/arch/loongarch/kernel/unwind_prologue.c b/arch/loongarch/kernel/unwind_prologue.c
index 55afc27..929ae24 100644 (file)
--- a/arch/loongarch/kernel/unwind_prologue.c
+++ b/arch/loongarch/kernel/unwind_prologue.c
@@ -227,7 +227,7 @@ static bool next_frame(struct unwind_state *state)
        } while (!get_stack_info(state->sp, state->task, info));
 
 out:
-       state->error = true;
+       state->stack_info.type = STACK_TYPE_UNKNOWN;
        return false;
 }