From 370a3b8f58743eceb97c5256538d6048c26d2d03 Mon Sep 17 00:00:00 2001 From: Tiezhu Yang Date: Wed, 19 Apr 2023 12:07:27 +0800 Subject: LoongArch: Check unwind_error() in arch_stack_walk() We can see the following messages with CONFIG_PROVE_LOCKING=y on LoongArch: BUG: MAX_STACK_TRACE_ENTRIES too low! turning off the locking correctness validator. This is because stack_trace_save() returns a big value after call arch_stack_walk(), here is the call trace: save_trace() stack_trace_save() arch_stack_walk() stack_trace_consume_entry() arch_stack_walk() should return immediately if unwind_next_frame() failed, no need to do the useless loops to increase the value of c->len in stack_trace_consume_entry(), then we can fix the above problem. Cc: stable@vger.kernel.org Reported-by: Guenter Roeck Link: https://lore.kernel.org/all/8a44ad71-68d2-4926-892f-72bfc7a67e2a@roeck-us.net/ Signed-off-by: Tiezhu Yang Signed-off-by: Huacai Chen --- arch/loongarch/kernel/stacktrace.c | 2 +- arch/loongarch/kernel/unwind.c | 1 + arch/loongarch/kernel/unwind_prologue.c | 4 +++- 3 files changed, 5 insertions(+), 2 deletions(-) (limited to 'arch/loongarch') diff --git a/arch/loongarch/kernel/stacktrace.c b/arch/loongarch/kernel/stacktrace.c index 3a690f96f00c..2463d2fea21f 100644 --- a/arch/loongarch/kernel/stacktrace.c +++ b/arch/loongarch/kernel/stacktrace.c @@ -30,7 +30,7 @@ void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie, regs->regs[1] = 0; for (unwind_start(&state, task, regs); - !unwind_done(&state); unwind_next_frame(&state)) { + !unwind_done(&state) && !unwind_error(&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 a463d6961344..ba324ba76fa1 100644 --- a/arch/loongarch/kernel/unwind.c +++ b/arch/loongarch/kernel/unwind.c @@ -28,5 +28,6 @@ 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 9095fde8e55d..55afc27320e1 100644 --- a/arch/loongarch/kernel/unwind_prologue.c +++ b/arch/loongarch/kernel/unwind_prologue.c @@ -211,7 +211,7 @@ static bool next_frame(struct unwind_state *state) pc = regs->csr_era; if (user_mode(regs) || !__kernel_text_address(pc)) - return false; + goto out; state->first = true; state->pc = pc; @@ -226,6 +226,8 @@ static bool next_frame(struct unwind_state *state) } while (!get_stack_info(state->sp, state->task, info)); +out: + state->error = true; return false; } -- cgit v1.2.3