From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8A662ECAAA3 for ; Fri, 26 Aug 2022 07:44:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245379AbiHZHoT (ORCPT ); Fri, 26 Aug 2022 03:44:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44276 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245487AbiHZHoN (ORCPT ); Fri, 26 Aug 2022 03:44:13 -0400 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7487FC2EBB; Fri, 26 Aug 2022 00:44:06 -0700 (PDT) Received: from dggemv703-chm.china.huawei.com (unknown [172.30.72.56]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4MDWy616HNzGprJ; Fri, 26 Aug 2022 15:42:22 +0800 (CST) Received: from kwepemm600010.china.huawei.com (7.193.23.86) by dggemv703-chm.china.huawei.com (10.3.19.46) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Fri, 26 Aug 2022 15:44:03 +0800 Received: from ubuntu1804.huawei.com (10.67.174.174) by kwepemm600010.china.huawei.com (7.193.23.86) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Fri, 26 Aug 2022 15:44:02 +0800 From: Li Huafei To: , , , , , CC: , , , , , , , , , , , , , , , , , , Subject: [PATCH RESEND v3 4/4] ARM: stacktrace: Convert stacktrace to generic ARCH_STACKWALK Date: Fri, 26 Aug 2022 15:40:47 +0800 Message-ID: <20220826074047.107357-5-lihuafei1@huawei.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220826074047.107357-1-lihuafei1@huawei.com> References: <20220826074047.107357-1-lihuafei1@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.67.174.174] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To kwepemm600010.china.huawei.com (7.193.23.86) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Historically architectures have had duplicated code in their stack trace implementations for filtering what gets traced. In order to avoid this duplication some generic code has been provided using a new interface arch_stack_walk(), enabled by selecting ARCH_STACKWALK in Kconfig, which factors all this out into the generic stack trace code. Convert ARM to use this common infrastructure. When initializing the stack frame of the current task, arm64 uses __builtin_frame_address(1) to initialize the frame pointer, skipping arch_stack_walk(), see the commit c607ab4f916d ("arm64: stacktrace: don't trace arch_ stack_walk()"). Since __builtin_frame_address(1) does not work on ARM, unwind_frame() is used to unwind the stack one layer forward before calling walk_stackframe(). Signed-off-by: Li Huafei Reviewed-by: Linus Walleij --- arch/arm/Kconfig | 1 + arch/arm/kernel/stacktrace.c | 114 ++++++++++------------------------- 2 files changed, 33 insertions(+), 82 deletions(-) diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 87badeae3181..3a8abc84260a 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -17,6 +17,7 @@ config ARM select ARCH_HAS_PTE_SPECIAL if ARM_LPAE select ARCH_HAS_SETUP_DMA_OPS select ARCH_HAS_SET_MEMORY + select ARCH_STACKWALK select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL select ARCH_HAS_STRICT_MODULE_RWX if MMU select ARCH_HAS_SYNC_DMA_FOR_DEVICE diff --git a/arch/arm/kernel/stacktrace.c b/arch/arm/kernel/stacktrace.c index d05968bc7812..620aa82e3bdd 100644 --- a/arch/arm/kernel/stacktrace.c +++ b/arch/arm/kernel/stacktrace.c @@ -142,40 +142,32 @@ void notrace walk_stackframe(struct stackframe *frame, EXPORT_SYMBOL(walk_stackframe); #ifdef CONFIG_STACKTRACE -struct stack_trace_data { - struct stack_trace *trace; - unsigned int no_sched_functions; - unsigned int skip; -}; - -static bool save_trace(void *d, unsigned long addr) +static void start_stack_trace(struct stackframe *frame, struct task_struct *task, + unsigned long fp, unsigned long sp, + unsigned long lr, unsigned long pc) { - struct stack_trace_data *data = d; - struct stack_trace *trace = data->trace; - - if (data->no_sched_functions && in_sched_functions(addr)) - return true; - if (data->skip) { - data->skip--; - return true; - } - - trace->entries[trace->nr_entries++] = addr; - return trace->nr_entries < trace->max_entries; + frame->fp = fp; + frame->sp = sp; + frame->lr = lr; + frame->pc = pc; +#ifdef CONFIG_KRETPROBES + frame->kr_cur = NULL; + frame->tsk = task; +#endif +#ifdef CONFIG_UNWINDER_FRAME_POINTER + frame->ex_frame = in_entry_text(frame->pc); +#endif } -/* This must be noinline to so that our skip calculation works correctly */ -static noinline void __save_stack_trace(struct task_struct *tsk, - struct stack_trace *trace, unsigned int nosched) +void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie, + struct task_struct *task, struct pt_regs *regs) { - struct stack_trace_data data; struct stackframe frame; - data.trace = trace; - data.skip = trace->skip; - data.no_sched_functions = nosched; - - if (tsk != current) { + if (regs) { + start_stack_trace(&frame, NULL, regs->ARM_fp, regs->ARM_sp, + regs->ARM_lr, regs->ARM_pc); + } else if (task != current) { #ifdef CONFIG_SMP /* * What guarantees do we have here that 'tsk' is not @@ -184,64 +176,22 @@ static noinline void __save_stack_trace(struct task_struct *tsk, */ return; #else - frame.fp = thread_saved_fp(tsk); - frame.sp = thread_saved_sp(tsk); - frame.lr = 0; /* recovered from the stack */ - frame.pc = thread_saved_pc(tsk); + start_stack_trace(&frame, task, thread_saved_fp(task), + thread_saved_sp(task), 0, + thread_saved_pc(task)); #endif } else { - /* We don't want this function nor the caller */ - data.skip += 2; - frame.fp = (unsigned long)__builtin_frame_address(0); - frame.sp = current_stack_pointer; - frame.lr = (unsigned long)__builtin_return_address(0); here: - frame.pc = (unsigned long)&&here; + start_stack_trace(&frame, task, + (unsigned long)__builtin_frame_address(0), + current_stack_pointer, + (unsigned long)__builtin_return_address(0), + (unsigned long)&&here); + /* skip this function */ + if (unwind_frame(&frame)) + return; } -#ifdef CONFIG_KRETPROBES - frame.kr_cur = NULL; - frame.tsk = tsk; -#endif -#ifdef CONFIG_UNWINDER_FRAME_POINTER - frame.ex_frame = false; -#endif - walk_stackframe(&frame, save_trace, &data); -} - -void save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace) -{ - struct stack_trace_data data; - struct stackframe frame; - - data.trace = trace; - data.skip = trace->skip; - data.no_sched_functions = 0; - - frame.fp = regs->ARM_fp; - frame.sp = regs->ARM_sp; - frame.lr = regs->ARM_lr; - frame.pc = regs->ARM_pc; -#ifdef CONFIG_KRETPROBES - frame.kr_cur = NULL; - frame.tsk = current; -#endif -#ifdef CONFIG_UNWINDER_FRAME_POINTER - frame.ex_frame = in_entry_text(frame.pc); -#endif - - walk_stackframe(&frame, save_trace, &data); -} - -void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) -{ - __save_stack_trace(tsk, trace, 1); -} -EXPORT_SYMBOL(save_stack_trace_tsk); - -void save_stack_trace(struct stack_trace *trace) -{ - __save_stack_trace(current, trace, 0); + walk_stackframe(&frame, consume_entry, cookie); } -EXPORT_SYMBOL_GPL(save_stack_trace); #endif -- 2.17.1