From patchwork Wed Apr 13 14:05:23 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Madhavan T. Venkataraman" X-Patchwork-Id: 12812067 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 78D1BC433F5 for ; Wed, 13 Apr 2022 14:07:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Cc:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=rFPke6h1d6H80f5iRon3A61OkMKM3QlmCRuWMT/SZv4=; b=NTdQ3u3ZEQ3b3B X8nTkqNkWVx88qD7c2ogvLMYrmhruRUp9s6ut79gUdmgCdQjAmm/EuhF/KMveGPwxH0HR065caSL/ k8nsXg7UOaUSAS93vf3Hy4HouUhV1QF0/l3+LpfIgchIPB6a2KUAd55UnIBlHjW9EJopU7kcbJ/0N 4bMFCq4mDz4dY9Cx9lVqL4FWd/s3lx/RziJ1ZOezzx3iOr8yUjf7HA+1zL+9S0GWYBs4WcBzMc7DH K4HNZknIZTk4dukq1Ll6mWDSZYo34sv83siDSb+/KGdWzfsqu2jL6Nwe+7ib3P7zmdCG6uaRLrkl8 77M8zcX4XVLTCQkCz8EQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nedcz-001JpM-MU; Wed, 13 Apr 2022 14:05:49 +0000 Received: from linux.microsoft.com ([13.77.154.182]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nedcw-001Jmx-Cd for linux-arm-kernel@lists.infradead.org; Wed, 13 Apr 2022 14:05:48 +0000 Received: from x64host.home (unknown [47.189.24.195]) by linux.microsoft.com (Postfix) with ESMTPSA id F19EE20C34CC; Wed, 13 Apr 2022 07:05:43 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com F19EE20C34CC DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1649858744; bh=KOgylemXULSWKrdPAi67ieZBj5vfyVJl5HzFLzKmkho=; h=From:To:Subject:Date:In-Reply-To:References:From; b=S5jE7GT61Gs8LdhPjb8sokZY07qlBfYXhVovpHnlqaICQ5dS21wg4bWW1JRTAuKvS sP4n6b5Aj9SpTc/RfaXCBHKZxqI+0kB4+L7PZ1a++6IRWMGPfhvXs7IsUBR/hjYCXB 2kQgtJJD7pFbwK3j08/RR4k+s8js3PuODxP4XFSA= From: madvenka@linux.microsoft.com To: mark.rutland@arm.com, broonie@kernel.org, jpoimboe@redhat.com, ardb@kernel.org, nobuta.keiya@fujitsu.com, sjitindarsingh@gmail.com, catalin.marinas@arm.com, will@kernel.org, jmorris@namei.org, linux-arm-kernel@lists.infradead.org, live-patching@vger.kernel.org, linux-kernel@vger.kernel.org, madvenka@linux.microsoft.com Subject: [PATCH v14 2/7] arm64: Copy the task argument to unwind_state Date: Wed, 13 Apr 2022 09:05:23 -0500 Message-Id: <20220413140528.3815-3-madvenka@linux.microsoft.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220413140528.3815-1-madvenka@linux.microsoft.com> References: <20220413140528.3815-1-madvenka@linux.microsoft.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220413_070546_533571_5935A147 X-CRM114-Status: GOOD ( 15.54 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: "Madhavan T. Venkataraman" Copy the task argument passed to arch_stack_walk() to unwind_state so that it can be passed to unwind functions via unwind_state rather than as a separate argument. The task is a fundamental part of the unwind state. Signed-off-by: Madhavan T. Venkataraman Reviewed-by: Mark Brown --- arch/arm64/kernel/stacktrace.c | 33 ++++++++++++++++++++------------- 1 file changed, 20 insertions(+), 13 deletions(-) diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c index e44f93ff25f0..8e43444d50e2 100644 --- a/arch/arm64/kernel/stacktrace.c +++ b/arch/arm64/kernel/stacktrace.c @@ -38,6 +38,8 @@ * @kr_cur: When KRETPROBES is selected, holds the kretprobe instance * associated with the most recently encountered replacement lr * value. + * + * @task: The task being unwound. */ struct unwind_state { unsigned long fp; @@ -48,10 +50,13 @@ struct unwind_state { #ifdef CONFIG_KRETPROBES struct llist_node *kr_cur; #endif + struct task_struct *task; }; -static void unwind_init_common(struct unwind_state *state) +static void unwind_init_common(struct unwind_state *state, + struct task_struct *task) { + state->task = task; #ifdef CONFIG_KRETPROBES state->kr_cur = NULL; #endif @@ -80,7 +85,7 @@ static void unwind_init_common(struct unwind_state *state) static inline void unwind_init_from_regs(struct unwind_state *state, struct pt_regs *regs) { - unwind_init_common(state); + unwind_init_common(state, current); state->fp = regs->regs[29]; state->pc = regs->pc; @@ -96,7 +101,7 @@ static inline void unwind_init_from_regs(struct unwind_state *state, */ static __always_inline void unwind_init_from_caller(struct unwind_state *state) { - unwind_init_common(state); + unwind_init_common(state, current); state->fp = (unsigned long)__builtin_frame_address(1); state->pc = (unsigned long)__builtin_return_address(0); @@ -115,7 +120,7 @@ static __always_inline void unwind_init_from_caller(struct unwind_state *state) static inline void unwind_init_from_task(struct unwind_state *state, struct task_struct *task) { - unwind_init_common(state); + unwind_init_common(state, task); state->fp = thread_saved_fp(task); state->pc = thread_saved_pc(task); @@ -128,9 +133,9 @@ static inline void unwind_init_from_task(struct unwind_state *state, * records (e.g. a cycle), determined based on the location and fp value of A * and the location (but not the fp value) of B. */ -static int notrace unwind_next(struct task_struct *tsk, - struct unwind_state *state) +static int notrace unwind_next(struct unwind_state *state) { + struct task_struct *tsk = state->task; unsigned long fp = state->fp; struct stack_info info; @@ -204,8 +209,7 @@ static int notrace unwind_next(struct task_struct *tsk, } NOKPROBE_SYMBOL(unwind_next); -static void notrace unwind(struct task_struct *tsk, - struct unwind_state *state, +static void notrace unwind(struct unwind_state *state, stack_trace_consume_fn consume_entry, void *cookie) { while (1) { @@ -213,7 +217,7 @@ static void notrace unwind(struct task_struct *tsk, if (!consume_entry(cookie, state->pc)) break; - ret = unwind_next(tsk, state); + ret = unwind_next(state); if (ret < 0) break; } @@ -259,12 +263,15 @@ noinline notrace void arch_stack_walk(stack_trace_consume_fn consume_entry, { struct unwind_state state; - if (regs) + if (regs) { + if (task != current) + return; unwind_init_from_regs(&state, regs); - else if (task == current) + } else if (task == current) { unwind_init_from_caller(&state); - else + } else { unwind_init_from_task(&state, task); + } - unwind(task, &state, consume_entry, cookie); + unwind(&state, consume_entry, cookie); }