From patchwork Thu Apr 25 09:45:18 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 10916693 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 52C0E13B5 for ; Thu, 25 Apr 2019 10:01:46 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4076F28A08 for ; Thu, 25 Apr 2019 10:01:46 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3378128C53; Thu, 25 Apr 2019 10:01:46 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D3CA028A08 for ; Thu, 25 Apr 2019 10:01:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729177AbfDYKBo (ORCPT ); Thu, 25 Apr 2019 06:01:44 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:58147 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728108AbfDYKBo (ORCPT ); Thu, 25 Apr 2019 06:01:44 -0400 Received: from localhost ([127.0.0.1] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1hJbAK-0001yx-7e; Thu, 25 Apr 2019 11:59:40 +0200 Message-Id: <20190425094803.437950229@linutronix.de> User-Agent: quilt/0.65 Date: Thu, 25 Apr 2019 11:45:18 +0200 From: Thomas Gleixner To: LKML Cc: Josh Poimboeuf , x86@kernel.org, Andy Lutomirski , Miroslav Benes , Steven Rostedt , Alexander Potapenko , Alexey Dobriyan , Andrew Morton , Christoph Lameter , Pekka Enberg , linux-mm@kvack.org, David Rientjes , Catalin Marinas , Dmitry Vyukov , Andrey Ryabinin , kasan-dev@googlegroups.com, Mike Rapoport , Akinobu Mita , Christoph Hellwig , iommu@lists.linux-foundation.org, Robin Murphy , Marek Szyprowski , Johannes Thumshirn , David Sterba , Chris Mason , Josef Bacik , linux-btrfs@vger.kernel.org, dm-devel@redhat.com, Mike Snitzer , Alasdair Kergon , Daniel Vetter , intel-gfx@lists.freedesktop.org, Joonas Lahtinen , Maarten Lankhorst , dri-devel@lists.freedesktop.org, David Airlie , Jani Nikula , Rodrigo Vivi , Tom Zanussi , linux-arch@vger.kernel.org Subject: [patch V3 25/29] livepatch: Simplify stack trace retrieval References: <20190425094453.875139013@linutronix.de> MIME-Version: 1.0 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Replace the indirection through struct stack_trace by using the storage array based interfaces. Signed-off-by: Thomas Gleixner Acked-by: Miroslav Benes --- kernel/livepatch/transition.c | 22 +++++++++------------- 1 file changed, 9 insertions(+), 13 deletions(-) --- a/kernel/livepatch/transition.c +++ b/kernel/livepatch/transition.c @@ -202,15 +202,15 @@ void klp_update_patch_state(struct task_ * Determine whether the given stack trace includes any references to a * to-be-patched or to-be-unpatched function. */ -static int klp_check_stack_func(struct klp_func *func, - struct stack_trace *trace) +static int klp_check_stack_func(struct klp_func *func, unsigned long *entries, + unsigned int nr_entries) { unsigned long func_addr, func_size, address; struct klp_ops *ops; int i; - for (i = 0; i < trace->nr_entries; i++) { - address = trace->entries[i]; + for (i = 0; i < nr_entries; i++) { + address = entries[i]; if (klp_target_state == KLP_UNPATCHED) { /* @@ -254,29 +254,25 @@ static int klp_check_stack_func(struct k static int klp_check_stack(struct task_struct *task, char *err_buf) { static unsigned long entries[MAX_STACK_ENTRIES]; - struct stack_trace trace; struct klp_object *obj; struct klp_func *func; - int ret; + int ret, nr_entries; - trace.skip = 0; - trace.nr_entries = 0; - trace.max_entries = MAX_STACK_ENTRIES; - trace.entries = entries; - ret = save_stack_trace_tsk_reliable(task, &trace); + ret = stack_trace_save_tsk_reliable(task, entries, ARRAY_SIZE(entries)); WARN_ON_ONCE(ret == -ENOSYS); - if (ret) { + if (ret < 0) { snprintf(err_buf, STACK_ERR_BUF_SIZE, "%s: %s:%d has an unreliable stack\n", __func__, task->comm, task->pid); return ret; } + nr_entries = ret; klp_for_each_object(klp_transition_patch, obj) { if (!obj->patched) continue; klp_for_each_func(obj, func) { - ret = klp_check_stack_func(func, &trace); + ret = klp_check_stack_func(func, entries, nr_entries); if (ret) { snprintf(err_buf, STACK_ERR_BUF_SIZE, "%s: %s:%d is sleeping on function %s\n",