From patchwork Tue Jun 11 15:00:59 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiang Liu X-Patchwork-Id: 2704701 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: X-Original-To: patchwork-linux-pci@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 6A2F2C1459 for ; Tue, 11 Jun 2013 15:01:15 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 0660520288 for ; Tue, 11 Jun 2013 15:01:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A3A302028A for ; Tue, 11 Jun 2013 15:01:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753985Ab3FKPBH (ORCPT ); Tue, 11 Jun 2013 11:01:07 -0400 Received: from mail-pb0-f47.google.com ([209.85.160.47]:35921 "EHLO mail-pb0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753803Ab3FKPBH (ORCPT ); Tue, 11 Jun 2013 11:01:07 -0400 Received: by mail-pb0-f47.google.com with SMTP id rr13so5929775pbb.20 for ; Tue, 11 Jun 2013 08:01:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; bh=R4Pa+tRJzt/Pd6yJyJypsQXNkix0m0DIkpVUrxZFCnM=; b=ZkX3jBOT9V7iL+2xQ4IYBeVYoYxzBvRKDtKAuqvh3HCr0vJ1i42+KmWX3VOTH74hW4 MuWW99Dwk98utgWGq8k6wVGUkh4VJ4omknM3XGB7WuklzguLhJtMOIJPa4sjtHew7K/T HwkaE3I8VdLuRP2tagM6o5bVvRHY1kBN4SeS/B56uOxU+JwuL37NDAcTglYzhIkTbnSu OV+Ku9JhBew4NYm4xiwqOQzVNit30NJ7bk8NU1FkCelaeRNoPdNqlY9R7Bfmh+cowi3q TslhO12cPyVJfb2SEFWazF7+DWtbnf+XIOjZKLwjYlNaDSnffSm/g4glRjEPjBc7zFqE xeHA== X-Received: by 10.66.250.164 with SMTP id zd4mr19365395pac.141.1370962866456; Tue, 11 Jun 2013 08:01:06 -0700 (PDT) Received: from [192.168.1.105] ([114.250.74.54]) by mx.google.com with ESMTPSA id pq5sm11066200pbc.7.2013.06.11.08.01.01 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 11 Jun 2013 08:01:05 -0700 (PDT) Message-ID: <51B73BAB.3030406@gmail.com> Date: Tue, 11 Jun 2013 23:00:59 +0800 From: Jiang Liu User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130404 Thunderbird/17.0.5 MIME-Version: 1.0 To: "Alexander E. Patrakov" CC: Jiang Liu , Bjorn Helgaas , Yinghai Lu , "Rafael J. Wysocki" , linux-pci@vger.kernel.org, "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] ACPIPHP: fix device destroying order issue in handling dock notification References: <1370951543-15841-1-git-send-email-jiang.liu@huawei.com> <51B7170E.2060608@gmail.com> In-Reply-To: Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Spam-Status: No, score=-7.0 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, T_DKIM_INVALID, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Hi Alexander, This is much more harder issue to resolve. Let's first work around this issue and check whether other things are OK. The patch below is just a prove of concept, could you please help to try it? Regards! Gerry --- --- On Tue 11 Jun 2013 09:38:59 PM CST, Alexander E. Patrakov wrote: > 2013/6/11 Jiang Liu : >> Hi Alexander, >> Sorry for the deadlock, I have no machine for testing:( >> Below patch should fix the deadlock issue. > > There is another deadlock: > > [ 34.316382] acpiphp_glue: found ACPI PCI Hotplug slot 1 at PCI 0000:0a:00 > [ 34.316557] acpiphp: Slot [1-1] registered > > [ 34.316569] ============================================= > [ 34.316570] [ INFO: possible recursive locking detected ] > [ 34.316573] 3.10.0-rc4 #6 Tainted: G C > [ 34.316575] --------------------------------------------- > [ 34.316577] kworker/0:0/4 is trying to acquire lock: > [ 34.316579] (&dock_station->hp_lock){+.+.+.}, at: > [] register_hotplug_dock_device+0x6a/0xbf > [ 34.316588] > but task is already holding lock: > [ 34.316590] (&dock_station->hp_lock){+.+.+.}, at: > [] hotplug_dock_devices+0x2c/0xda > [ 34.316595] > other info that might help us debug this: > [ 34.316597] Possible unsafe locking scenario: > > [ 34.316599] CPU0 > [ 34.316601] ---- > [ 34.316602] lock(&dock_station->hp_lock); > [ 34.316605] lock(&dock_station->hp_lock); > [ 34.316608] > *** DEADLOCK *** > > [ 34.316611] May be due to missing lock nesting notation > > [ 34.316613] 5 locks held by kworker/0:0/4: > [ 34.316615] #0: (kacpi_hotplug){.+.+.+}, at: [] > process_one_work+0x157/0x560 > [ 34.316624] #1: ((&dpc->work)#3){+.+.+.}, at: > [] process_one_work+0x157/0x560 > [ 34.316631] #2: (acpi_scan_lock){+.+.+.}, at: > [] acpi_scan_lock_acquire+0x12/0x14 > [ 34.316639] #3: (&dock_station->hp_lock){+.+.+.}, at: > [] hotplug_dock_devices+0x2c/0xda > [ 34.316646] #4: (&slot->crit_sect){+.+.+.}, at: > [] acpiphp_enable_slot+0x1e/0x140 > [ 34.316653] > stack backtrace: > [ 34.316657] CPU: 0 PID: 4 Comm: kworker/0:0 Tainted: G C > 3.10.0-rc4 #6 > [ 34.316659] Hardware name: Sony Corporation VPCZ23A4R/VAIO, BIOS > R1013H5 05/21/2012 > [ 34.316663] Workqueue: kacpi_hotplug acpi_os_execute_deferred > [ 34.316665] ffff8802540adf40 ffff8802540d3628 ffffffff8165aaf8 > ffff8802540d3718 > [ 34.316670] ffffffff8109fe92 ffff8802540adf40 ffffffff8261c8a0 > ffff8802540ae700 > [ 34.316675] 0000000000000000 ffff8802540d3748 000000000001f180 > ffff8802000000dc > [ 34.316680] Call Trace: > [ 34.316685] [] dump_stack+0x19/0x1b > [ 34.316689] [] __lock_acquire+0x1522/0x1ee0 > [ 34.316693] [] ? mark_held_locks+0x61/0x150 > [ 34.316697] [] ? _raw_spin_unlock_irqrestore+0x65/0x80 > [ 34.316702] [] ? acpi_ns_get_node+0xb2/0xc2 > [ 34.316705] [] ? register_hotplug_dock_device+0x6a/0xbf > [ 34.316709] [] lock_acquire+0x87/0x150 > [ 34.316712] [] ? register_hotplug_dock_device+0x6a/0xbf > [ 34.316715] [] ? register_hotplug_dock_device+0x6a/0xbf > [ 34.316720] [] mutex_lock_nested+0x5e/0x3e0 > [ 34.316723] [] ? register_hotplug_dock_device+0x6a/0xbf > [ 34.316726] [] ? _raw_spin_unlock+0x30/0x60 > [ 34.316729] [] register_hotplug_dock_device+0x6a/0xbf > [ 34.316733] [] register_slot+0x467/0x5b0 > [ 34.316738] [] acpi_ns_walk_namespace+0xbb/0x17b > [ 34.316741] [] ? acpi_os_wait_semaphore+0x3f/0x55 > [ 34.316744] [] ? free_bridge+0x100/0x100 > [ 34.316748] [] ? free_bridge+0x100/0x100 > [ 34.316752] [] acpi_walk_namespace+0x8e/0xc8 > [ 34.316755] [] acpiphp_enumerate_slots+0x1bd/0x320 > [ 34.316760] [] ? pm_runtime_init+0x106/0x110 > [ 34.316764] [] acpi_pci_add_bus+0x2f/0x40 > [ 34.316768] [] pcibios_add_bus+0x9/0x10 > [ 34.316772] [] pci_add_new_bus+0x1c8/0x390 > [ 34.316777] [] pci_scan_bridge+0x5e5/0x620 > [ 34.316781] [] enable_device+0x169/0x450 > [ 34.316785] [] acpiphp_enable_slot+0xca/0x140 > [ 34.316789] [] __handle_hotplug_event_func+0x96/0x1a0 > [ 34.316792] [] hotplug_dock_devices+0x57/0xda > [ 34.316796] [] acpi_dock_deferred_cb+0xd4/0x1c8 > [ 34.316799] [] acpi_os_execute_deferred+0x20/0x2d > [ 34.316803] [] process_one_work+0x1c2/0x560 > [ 34.316807] [] ? process_one_work+0x157/0x560 > [ 34.316810] [] worker_thread+0x116/0x370 > [ 34.316813] [] ? manage_workers.isra.20+0x2d0/0x2d0 > [ 34.316818] [] kthread+0xd6/0xe0 > [ 34.316821] [] ? _raw_spin_unlock_irq+0x2b/0x60 > [ 34.316826] [] ? __init_kthread_worker+0x70/0x70 > [ 34.316830] [] ret_from_fork+0x7c/0xb0 > [ 34.316834] [] ? __init_kthread_worker+0x70/0x70 > >> Regards! >> >> ---- >> diff --git a/drivers/pci/hotplug/acpiphp_glue.c >> b/drivers/pci/hotplug/acpiphp_glue.c >> index 0302645..699b8ca 100644 >> --- a/drivers/pci/hotplug/acpiphp_glue.c >> +++ b/drivers/pci/hotplug/acpiphp_glue.c >> @@ -1075,8 +1075,6 @@ static void >> _handle_hotplug_event_func(acpi_handle handle, u32 type, >> struct acpi_buffer buffer = { .length = sizeof(objname), >> .pointer = objname }; >> >> - acpi_scan_lock_acquire(); >> - >> acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer); >> >> switch (type) { >> @@ -1108,8 +1106,6 @@ static void >> _handle_hotplug_event_func(acpi_handle handle, u32 type, >> warn("notify_handler: unknown event type 0x%x for >> %s\n", type, objname); >> break; >> } >> - >> - acpi_scan_lock_release(); >> } >> >> static void _handle_hotplug_event_cb(struct work_struct *work) >> @@ -1119,8 +1115,10 @@ static void _handle_hotplug_event_cb(struct >> work_struct *work) >> >> hp_work = container_of(work, struct acpi_hp_work, work); >> func = (struct acpiphp_func *)hp_work->context; >> + acpi_scan_lock_acquire(); >> _handle_hotplug_event_func(hp_work->handle, hp_work->type, >> hp_work->context); >> + acpi_scan_lock_release(); >> kfree(hp_work); /* allocated in handle_hotplug_event_func */ >> put_bridge(func->slot->bridge); >> } >> > > > > -- > Alexander E. Patrakov -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/drivers/acpi/dock.c b/drivers/acpi/dock.c index a7ba608..dde1cec 100644 --- a/drivers/acpi/dock.c +++ b/drivers/acpi/dock.c @@ -121,9 +121,7 @@ static void dock_add_hotplug_device(struct dock_station *ds, struct dock_dependent_device *dd) { - mutex_lock(&ds->hp_lock); list_add_tail(&dd->hotplug_list, &ds->hotplug_devices); - mutex_unlock(&ds->hp_lock); } /** @@ -137,9 +135,7 @@ static void dock_del_hotplug_device(struct dock_station *ds, struct dock_dependent_device *dd) { - mutex_lock(&ds->hp_lock); list_del_init(&dd->hotplug_list); - mutex_unlock(&ds->hp_lock); } /**