From patchwork Sat Mar 21 11:25:45 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 222110 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 11EAFC4332B for ; Sat, 21 Mar 2020 11:35:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E02D320658 for ; Sat, 21 Mar 2020 11:35:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728816AbgCULfq (ORCPT ); Sat, 21 Mar 2020 07:35:46 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:38509 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728584AbgCULfA (ORCPT ); Sat, 21 Mar 2020 07:35:00 -0400 Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jFcOQ-0001zG-FR; Sat, 21 Mar 2020 12:34:18 +0100 Received: from nanos.tec.linutronix.de (localhost [IPv6:::1]) by nanos.tec.linutronix.de (Postfix) with ESMTP id 6AF95FFC8D; Sat, 21 Mar 2020 12:34:17 +0100 (CET) Message-Id: <20200321113240.841963112@linutronix.de> User-Agent: quilt/0.65 Date: Sat, 21 Mar 2020 12:25:45 +0100 From: Thomas Gleixner To: LKML Cc: Peter Zijlstra , Ingo Molnar , Sebastian Siewior , Linus Torvalds , Joel Fernandes , Oleg Nesterov , Davidlohr Bueso , Logan Gunthorpe , Bjorn Helgaas , Kurt Schwemmer , linux-pci@vger.kernel.org, Greg Kroah-Hartman , Felipe Balbi , linux-usb@vger.kernel.org, Kalle Valo , "David S. Miller" , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, Darren Hart , Andy Shevchenko , platform-driver-x86@vger.kernel.org, Zhang Rui , "Rafael J. Wysocki" , linux-pm@vger.kernel.org, Len Brown , linux-acpi@vger.kernel.org, kbuild test robot , Nick Hu , Greentime Hu , Vincent Chen , Guo Ren , linux-csky@vger.kernel.org, Brian Cain , linux-hexagon@vger.kernel.org, Tony Luck , Fenghua Yu , linux-ia64@vger.kernel.org, Michal Simek , Michael Ellerman , Arnd Bergmann , Geoff Levand , linuxppc-dev@lists.ozlabs.org, "Paul E . McKenney" , Jonathan Corbet , Randy Dunlap , Davidlohr Bueso Subject: [patch V3 01/20] PCI/switchtec: Fix init_completion race condition with poll_wait() References: <20200321112544.878032781@linutronix.de> MIME-Version: 1.0 Content-transfer-encoding: 8-bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1, SHORTCIRCUIT=-0.0001 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Logan Gunthorpe The call to init_completion() in mrpc_queue_cmd() can theoretically race with the call to poll_wait() in switchtec_dev_poll(). poll() write() switchtec_dev_poll() switchtec_dev_write() poll_wait(&s->comp.wait); mrpc_queue_cmd() init_completion(&s->comp) init_waitqueue_head(&s->comp.wait) To my knowledge, no one has hit this bug. Fix this by using reinit_completion() instead of init_completion() in mrpc_queue_cmd(). Fixes: 080b47def5e5 ("MicroSemi Switchtec management interface driver") Reported-by: Sebastian Andrzej Siewior Signed-off-by: Logan Gunthorpe Signed-off-by: Thomas Gleixner Acked-by: Bjorn Helgaas Cc: Kurt Schwemmer Cc: linux-pci@vger.kernel.org Link: https://lkml.kernel.org/r/20200313183608.2646-1-logang@deltatee.com --- drivers/pci/switch/switchtec.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pci/switch/switchtec.c b/drivers/pci/switch/switchtec.c index a823b4b8ef8a..81dc7ac01381 100644 --- a/drivers/pci/switch/switchtec.c +++ b/drivers/pci/switch/switchtec.c @@ -175,7 +175,7 @@ static int mrpc_queue_cmd(struct switchtec_user *stuser) kref_get(&stuser->kref); stuser->read_len = sizeof(stuser->data); stuser_set_state(stuser, MRPC_QUEUED); - init_completion(&stuser->comp); + reinit_completion(&stuser->comp); list_add_tail(&stuser->list, &stdev->mrpc_queue); mrpc_cmd_submit(stdev); From patchwork Sat Mar 21 11:25:46 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 222108 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8849CC4332E for ; Sat, 21 Mar 2020 11:36:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 684AD20658 for ; Sat, 21 Mar 2020 11:36:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728609AbgCULe6 (ORCPT ); Sat, 21 Mar 2020 07:34:58 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:38471 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727071AbgCULe4 (ORCPT ); Sat, 21 Mar 2020 07:34:56 -0400 Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jFcOQ-0001zH-Br; Sat, 21 Mar 2020 12:34:18 +0100 Received: from nanos.tec.linutronix.de (localhost [IPv6:::1]) by nanos.tec.linutronix.de (Postfix) with ESMTP id AC6861039FD; Sat, 21 Mar 2020 12:34:17 +0100 (CET) Message-Id: <20200321113240.936097534@linutronix.de> User-Agent: quilt/0.65 Date: Sat, 21 Mar 2020 12:25:46 +0100 From: Thomas Gleixner To: LKML Cc: Peter Zijlstra , Ingo Molnar , Sebastian Siewior , Linus Torvalds , Joel Fernandes , Oleg Nesterov , Davidlohr Bueso , Logan Gunthorpe , Bjorn Helgaas , Kurt Schwemmer , linux-pci@vger.kernel.org, Greg Kroah-Hartman , Felipe Balbi , linux-usb@vger.kernel.org, Kalle Valo , "David S. Miller" , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, Darren Hart , Andy Shevchenko , platform-driver-x86@vger.kernel.org, Zhang Rui , "Rafael J. Wysocki" , linux-pm@vger.kernel.org, Len Brown , linux-acpi@vger.kernel.org, kbuild test robot , Nick Hu , Greentime Hu , Vincent Chen , Guo Ren , linux-csky@vger.kernel.org, Brian Cain , linux-hexagon@vger.kernel.org, Tony Luck , Fenghua Yu , linux-ia64@vger.kernel.org, Michal Simek , Michael Ellerman , Arnd Bergmann , Geoff Levand , linuxppc-dev@lists.ozlabs.org, "Paul E . McKenney" , Jonathan Corbet , Randy Dunlap , Davidlohr Bueso Subject: [patch V3 02/20] pci/switchtec: Replace completion wait queue usage for poll References: <20200321112544.878032781@linutronix.de> MIME-Version: 1.0 Content-transfer-encoding: 8-bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1, SHORTCIRCUIT=-0.0001 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Sebastian Andrzej Siewior The poll callback is using the completion wait queue and sticks it into poll_wait() to wake up pollers after a command has completed. This works to some extent, but cannot provide EPOLLEXCLUSIVE support because the waker side uses complete_all() which unconditionally wakes up all waiters. complete_all() is required because completions internally use exclusive wait and complete() only wakes up one waiter by default. This mixes conceptually different mechanisms and relies on internal implementation details of completions, which in turn puts contraints on changing the internal implementation of completions. Replace it with a regular wait queue and store the state in struct switchtec_user. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Reviewed-by: Logan Gunthorpe Acked-by: Peter Zijlstra (Intel) Acked-by: Bjorn Helgaas Cc: Kurt Schwemmer Cc: linux-pci@vger.kernel.org --- V2: Reworded changelog. --- drivers/pci/switch/switchtec.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) --- a/drivers/pci/switch/switchtec.c +++ b/drivers/pci/switch/switchtec.c @@ -52,10 +52,11 @@ struct switchtec_user { enum mrpc_state state; - struct completion comp; + wait_queue_head_t cmd_comp; struct kref kref; struct list_head list; + bool cmd_done; u32 cmd; u32 status; u32 return_code; @@ -77,7 +78,7 @@ static struct switchtec_user *stuser_cre stuser->stdev = stdev; kref_init(&stuser->kref); INIT_LIST_HEAD(&stuser->list); - init_completion(&stuser->comp); + init_waitqueue_head(&stuser->cmd_comp); stuser->event_cnt = atomic_read(&stdev->event_cnt); dev_dbg(&stdev->dev, "%s: %p\n", __func__, stuser); @@ -175,7 +176,7 @@ static int mrpc_queue_cmd(struct switcht kref_get(&stuser->kref); stuser->read_len = sizeof(stuser->data); stuser_set_state(stuser, MRPC_QUEUED); - reinit_completion(&stuser->comp); + stuser->cmd_done = false; list_add_tail(&stuser->list, &stdev->mrpc_queue); mrpc_cmd_submit(stdev); @@ -222,7 +223,8 @@ static void mrpc_complete_cmd(struct swi memcpy_fromio(stuser->data, &stdev->mmio_mrpc->output_data, stuser->read_len); out: - complete_all(&stuser->comp); + stuser->cmd_done = true; + wake_up_interruptible(&stuser->cmd_comp); list_del_init(&stuser->list); stuser_put(stuser); stdev->mrpc_busy = 0; @@ -529,10 +531,11 @@ static ssize_t switchtec_dev_read(struct mutex_unlock(&stdev->mrpc_mutex); if (filp->f_flags & O_NONBLOCK) { - if (!try_wait_for_completion(&stuser->comp)) + if (!stuser->cmd_done) return -EAGAIN; } else { - rc = wait_for_completion_interruptible(&stuser->comp); + rc = wait_event_interruptible(stuser->cmd_comp, + stuser->cmd_done); if (rc < 0) return rc; } @@ -580,7 +583,7 @@ static __poll_t switchtec_dev_poll(struc struct switchtec_dev *stdev = stuser->stdev; __poll_t ret = 0; - poll_wait(filp, &stuser->comp.wait, wait); + poll_wait(filp, &stuser->cmd_comp, wait); poll_wait(filp, &stdev->event_wq, wait); if (lock_mutex_and_test_alive(stdev)) @@ -588,7 +591,7 @@ static __poll_t switchtec_dev_poll(struc mutex_unlock(&stdev->mrpc_mutex); - if (try_wait_for_completion(&stuser->comp)) + if (stuser->cmd_done) ret |= EPOLLIN | EPOLLRDNORM; if (stuser->event_cnt != atomic_read(&stdev->event_cnt)) @@ -1272,7 +1275,8 @@ static void stdev_kill(struct switchtec_ /* Wake up and kill any users waiting on an MRPC request */ list_for_each_entry_safe(stuser, tmpuser, &stdev->mrpc_queue, list) { - complete_all(&stuser->comp); + stuser->cmd_done = true; + wake_up_interruptible(&stuser->cmd_comp); list_del_init(&stuser->list); stuser_put(stuser); } From patchwork Sat Mar 21 11:25:49 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 222109 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AFF86C43333 for ; Sat, 21 Mar 2020 11:35:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8732A20658 for ; Sat, 21 Mar 2020 11:35:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728637AbgCULe7 (ORCPT ); Sat, 21 Mar 2020 07:34:59 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:38490 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728497AbgCULe5 (ORCPT ); Sat, 21 Mar 2020 07:34:57 -0400 Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jFcOR-0001zT-Eh; Sat, 21 Mar 2020 12:34:19 +0100 Received: from nanos.tec.linutronix.de (localhost [IPv6:::1]) by nanos.tec.linutronix.de (Postfix) with ESMTP id 74A94FFBBF; Sat, 21 Mar 2020 12:34:18 +0100 (CET) Message-Id: <20200321113241.246190285@linutronix.de> User-Agent: quilt/0.65 Date: Sat, 21 Mar 2020 12:25:49 +0100 From: Thomas Gleixner To: LKML Cc: Peter Zijlstra , Ingo Molnar , Sebastian Siewior , Linus Torvalds , Joel Fernandes , Oleg Nesterov , Davidlohr Bueso , Darren Hart , Andy Shevchenko , platform-driver-x86@vger.kernel.org, Greg Kroah-Hartman , Zhang Rui , "Rafael J. Wysocki" , linux-pm@vger.kernel.org, Len Brown , linux-acpi@vger.kernel.org, Logan Gunthorpe , Bjorn Helgaas , Kurt Schwemmer , linux-pci@vger.kernel.org, Felipe Balbi , linux-usb@vger.kernel.org, Kalle Valo , "David S. Miller" , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, kbuild test robot , Nick Hu , Greentime Hu , Vincent Chen , Guo Ren , linux-csky@vger.kernel.org, Brian Cain , linux-hexagon@vger.kernel.org, Tony Luck , Fenghua Yu , linux-ia64@vger.kernel.org, Michal Simek , Michael Ellerman , Arnd Bergmann , Geoff Levand , linuxppc-dev@lists.ozlabs.org, "Paul E . McKenney" , Jonathan Corbet , Randy Dunlap , Davidlohr Bueso Subject: [patch V3 05/20] acpi: Remove header dependency References: <20200321112544.878032781@linutronix.de> MIME-Version: 1.0 Content-transfer-encoding: 8-bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1, SHORTCIRCUIT=-0.0001 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Peter Zijlstra In order to avoid future header hell, remove the inclusion of proc_fs.h from acpi_bus.h. All it needs is a forward declaration of a struct. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner Cc: Darren Hart Cc: Andy Shevchenko Cc: platform-driver-x86@vger.kernel.org Cc: Greg Kroah-Hartman Cc: Zhang Rui Cc: "Rafael J. Wysocki" Cc: linux-pm@vger.kernel.org Cc: Len Brown Cc: linux-acpi@vger.kernel.org --- drivers/platform/x86/dell-smo8800.c | 1 + drivers/platform/x86/wmi.c | 1 + drivers/thermal/intel/int340x_thermal/acpi_thermal_rel.c | 1 + include/acpi/acpi_bus.h | 2 +- 4 files changed, 4 insertions(+), 1 deletion(-) --- a/drivers/platform/x86/dell-smo8800.c +++ b/drivers/platform/x86/dell-smo8800.c @@ -16,6 +16,7 @@ #include #include #include +#include struct smo8800_device { u32 irq; /* acpi device irq */ --- a/drivers/platform/x86/wmi.c +++ b/drivers/platform/x86/wmi.c @@ -29,6 +29,7 @@ #include #include #include +#include #include ACPI_MODULE_NAME("wmi"); --- a/drivers/thermal/intel/int340x_thermal/acpi_thermal_rel.c +++ b/drivers/thermal/intel/int340x_thermal/acpi_thermal_rel.c @@ -19,6 +19,7 @@ #include #include #include +#include #include "acpi_thermal_rel.h" static acpi_handle acpi_thermal_rel_handle; --- a/include/acpi/acpi_bus.h +++ b/include/acpi/acpi_bus.h @@ -80,7 +80,7 @@ bool acpi_dev_present(const char *hid, c #ifdef CONFIG_ACPI -#include +struct proc_dir_entry; #define ACPI_BUS_FILE_ROOT "acpi" extern struct proc_dir_entry *acpi_root_dir; From patchwork Sat Mar 21 11:25:50 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 222105 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E4D60C4332B for ; Sat, 21 Mar 2020 11:37:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C63D520722 for ; Sat, 21 Mar 2020 11:37:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728927AbgCULhE (ORCPT ); Sat, 21 Mar 2020 07:37:04 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:38466 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727028AbgCULe4 (ORCPT ); Sat, 21 Mar 2020 07:34:56 -0400 Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jFcOR-0001zU-F0; Sat, 21 Mar 2020 12:34:19 +0100 Received: from nanos.tec.linutronix.de (localhost [IPv6:::1]) by nanos.tec.linutronix.de (Postfix) with ESMTP id B80C01039FD; Sat, 21 Mar 2020 12:34:18 +0100 (CET) Message-Id: <20200321113241.339289758@linutronix.de> User-Agent: quilt/0.65 Date: Sat, 21 Mar 2020 12:25:50 +0100 From: Thomas Gleixner To: LKML Cc: Peter Zijlstra , Ingo Molnar , Sebastian Siewior , Linus Torvalds , Joel Fernandes , Oleg Nesterov , Davidlohr Bueso , kbuild test robot , Nick Hu , Greentime Hu , Vincent Chen , Logan Gunthorpe , Bjorn Helgaas , Kurt Schwemmer , linux-pci@vger.kernel.org, Greg Kroah-Hartman , Felipe Balbi , linux-usb@vger.kernel.org, Kalle Valo , "David S. Miller" , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, Darren Hart , Andy Shevchenko , platform-driver-x86@vger.kernel.org, Zhang Rui , "Rafael J. Wysocki" , linux-pm@vger.kernel.org, Len Brown , linux-acpi@vger.kernel.org, Guo Ren , linux-csky@vger.kernel.org, Brian Cain , linux-hexagon@vger.kernel.org, Tony Luck , Fenghua Yu , linux-ia64@vger.kernel.org, Michal Simek , Michael Ellerman , Arnd Bergmann , Geoff Levand , linuxppc-dev@lists.ozlabs.org, "Paul E . McKenney" , Jonathan Corbet , Randy Dunlap , Davidlohr Bueso Subject: [patch V3 06/20] nds32: Remove mm.h from asm/uaccess.h References: <20200321112544.878032781@linutronix.de> MIME-Version: 1.0 Content-transfer-encoding: 8-bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1, SHORTCIRCUIT=-0.0001 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Sebastian Andrzej Siewior The defconfig compiles without linux/mm.h. With mm.h included the include chain leands to: | CC kernel/locking/percpu-rwsem.o | In file included from include/linux/huge_mm.h:8, | from include/linux/mm.h:567, | from arch/nds32/include/asm/uaccess.h:, | from include/linux/uaccess.h:11, | from include/linux/sched/task.h:11, | from include/linux/sched/signal.h:9, | from include/linux/rcuwait.h:6, | from include/linux/percpu-rwsem.h:8, | from kernel/locking/percpu-rwsem.c:6: | include/linux/fs.h:1422:29: error: array type has incomplete element type 'struct percpu_rw_semaphore' | 1422 | struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS]; once rcuwait.h includes linux/sched/signal.h. Remove the linux/mm.h include. Reported-by: kbuild test robot Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Cc: Nick Hu Cc: Greentime Hu Cc: Vincent Chen --- V3: New patch --- arch/nds32/include/asm/uaccess.h | 1 - 1 file changed, 1 deletion(-) diff --git a/arch/nds32/include/asm/uaccess.h b/arch/nds32/include/asm/uaccess.h index 8916ad9f9f139..3a9219f53ee0d 100644 --- a/arch/nds32/include/asm/uaccess.h +++ b/arch/nds32/include/asm/uaccess.h @@ -11,7 +11,6 @@ #include #include #include -#include #define __asmeq(x, y) ".ifnc " x "," y " ; .err ; .endif\n\t" From patchwork Sat Mar 21 11:25:51 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 222107 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0B6F4C43333 for ; Sat, 21 Mar 2020 11:36:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E002020658 for ; Sat, 21 Mar 2020 11:36:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728590AbgCULe5 (ORCPT ); Sat, 21 Mar 2020 07:34:57 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:38449 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726995AbgCULez (ORCPT ); Sat, 21 Mar 2020 07:34:55 -0400 Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jFcOW-0001zV-KV; Sat, 21 Mar 2020 12:34:24 +0100 Received: from nanos.tec.linutronix.de (localhost [IPv6:::1]) by nanos.tec.linutronix.de (Postfix) with ESMTP id 0A1D2FFC8D; Sat, 21 Mar 2020 12:34:19 +0100 (CET) Message-Id: <20200321113241.434999165@linutronix.de> User-Agent: quilt/0.65 Date: Sat, 21 Mar 2020 12:25:51 +0100 From: Thomas Gleixner To: LKML Cc: Peter Zijlstra , Ingo Molnar , Sebastian Siewior , Linus Torvalds , Joel Fernandes , Oleg Nesterov , Davidlohr Bueso , kbuild test robot , Guo Ren , linux-csky@vger.kernel.org, Logan Gunthorpe , Bjorn Helgaas , Kurt Schwemmer , linux-pci@vger.kernel.org, Greg Kroah-Hartman , Felipe Balbi , linux-usb@vger.kernel.org, Kalle Valo , "David S. Miller" , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, Darren Hart , Andy Shevchenko , platform-driver-x86@vger.kernel.org, Zhang Rui , "Rafael J. Wysocki" , linux-pm@vger.kernel.org, Len Brown , linux-acpi@vger.kernel.org, Nick Hu , Greentime Hu , Vincent Chen , Brian Cain , linux-hexagon@vger.kernel.org, Tony Luck , Fenghua Yu , linux-ia64@vger.kernel.org, Michal Simek , Michael Ellerman , Arnd Bergmann , Geoff Levand , linuxppc-dev@lists.ozlabs.org, "Paul E . McKenney" , Jonathan Corbet , Randy Dunlap , Davidlohr Bueso Subject: [patch V3 07/20] csky: Remove mm.h from asm/uaccess.h References: <20200321112544.878032781@linutronix.de> MIME-Version: 1.0 Content-transfer-encoding: 8-bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1, SHORTCIRCUIT=-0.0001 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Sebastian Andrzej Siewior The defconfig compiles without linux/mm.h. With mm.h included the include chain leands to: | CC kernel/locking/percpu-rwsem.o | In file included from include/linux/huge_mm.h:8, | from include/linux/mm.h:567, | from arch/csky/include/asm/uaccess.h:, | from include/linux/uaccess.h:11, | from include/linux/sched/task.h:11, | from include/linux/sched/signal.h:9, | from include/linux/rcuwait.h:6, | from include/linux/percpu-rwsem.h:8, | from kernel/locking/percpu-rwsem.c:6: | include/linux/fs.h:1422:29: error: array type has incomplete element type 'struct percpu_rw_semaphore' | 1422 | struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS]; once rcuwait.h includes linux/sched/signal.h. Remove the linux/mm.h include. Reported-by: kbuild test robot Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Cc: Guo Ren Cc: linux-csky@vger.kernel.org --- V3: New patch --- arch/csky/include/asm/uaccess.h | 1 - 1 file changed, 1 deletion(-) diff --git a/arch/csky/include/asm/uaccess.h b/arch/csky/include/asm/uaccess.h index eaa1c3403a424..abefa125b93cf 100644 --- a/arch/csky/include/asm/uaccess.h +++ b/arch/csky/include/asm/uaccess.h @@ -11,7 +11,6 @@ #include #include #include -#include #include #include #include From patchwork Sat Mar 21 11:25:54 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 222106 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A6D54C4332D for ; Sat, 21 Mar 2020 11:36:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 823A420722 for ; Sat, 21 Mar 2020 11:36:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728893AbgCULgg (ORCPT ); Sat, 21 Mar 2020 07:36:36 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:38489 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728493AbgCULe5 (ORCPT ); Sat, 21 Mar 2020 07:34:57 -0400 Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jFcOX-0001zf-CX; Sat, 21 Mar 2020 12:34:25 +0100 Received: from nanos.tec.linutronix.de (localhost [IPv6:::1]) by nanos.tec.linutronix.de (Postfix) with ESMTP id C92BE1040A1; Sat, 21 Mar 2020 12:34:19 +0100 (CET) Message-Id: <20200321113241.719022171@linutronix.de> User-Agent: quilt/0.65 Date: Sat, 21 Mar 2020 12:25:54 +0100 From: Thomas Gleixner To: LKML Cc: Peter Zijlstra , Ingo Molnar , Sebastian Siewior , Linus Torvalds , Joel Fernandes , Oleg Nesterov , Davidlohr Bueso , kbuild test robot , Michal Simek , Logan Gunthorpe , Bjorn Helgaas , Kurt Schwemmer , linux-pci@vger.kernel.org, Greg Kroah-Hartman , Felipe Balbi , linux-usb@vger.kernel.org, Kalle Valo , "David S. Miller" , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, Darren Hart , Andy Shevchenko , platform-driver-x86@vger.kernel.org, Zhang Rui , "Rafael J. Wysocki" , linux-pm@vger.kernel.org, Len Brown , linux-acpi@vger.kernel.org, Nick Hu , Greentime Hu , Vincent Chen , Guo Ren , linux-csky@vger.kernel.org, Brian Cain , linux-hexagon@vger.kernel.org, Tony Luck , Fenghua Yu , linux-ia64@vger.kernel.org, Michael Ellerman , Arnd Bergmann , Geoff Levand , linuxppc-dev@lists.ozlabs.org, "Paul E . McKenney" , Jonathan Corbet , Randy Dunlap , Davidlohr Bueso Subject: [patch V3 10/20] microblaze: Remove mm.h from asm/uaccess.h References: <20200321112544.878032781@linutronix.de> MIME-Version: 1.0 Content-transfer-encoding: 8-bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1, SHORTCIRCUIT=-0.0001 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Sebastian Andrzej Siewior The defconfig compiles without linux/mm.h. With mm.h included the include chain leands to: | CC kernel/locking/percpu-rwsem.o | In file included from include/linux/huge_mm.h:8, | from include/linux/mm.h:567, | from arch/microblaze/include/asm/uaccess.h:, | from include/linux/uaccess.h:11, | from include/linux/sched/task.h:11, | from include/linux/sched/signal.h:9, | from include/linux/rcuwait.h:6, | from include/linux/percpu-rwsem.h:8, | from kernel/locking/percpu-rwsem.c:6: | include/linux/fs.h:1422:29: error: array type has incomplete element type 'struct percpu_rw_semaphore' | 1422 | struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS]; once rcuwait.h includes linux/sched/signal.h. Remove the linux/mm.h include. Reported-by: kbuild test robot Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Cc: Michal Simek --- V3; New patch --- arch/microblaze/include/asm/uaccess.h | 1 - 1 file changed, 1 deletion(-) diff --git a/arch/microblaze/include/asm/uaccess.h b/arch/microblaze/include/asm/uaccess.h index a1f206b90753a..4916d5fbea5e3 100644 --- a/arch/microblaze/include/asm/uaccess.h +++ b/arch/microblaze/include/asm/uaccess.h @@ -12,7 +12,6 @@ #define _ASM_MICROBLAZE_UACCESS_H #include -#include #include #include From patchwork Sat Mar 21 11:26:01 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 222111 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EE946C4332D for ; Sat, 21 Mar 2020 11:35:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A4E2A20722 for ; Sat, 21 Mar 2020 11:35:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728769AbgCULfS (ORCPT ); Sat, 21 Mar 2020 07:35:18 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:38516 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726961AbgCULfG (ORCPT ); Sat, 21 Mar 2020 07:35:06 -0400 Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jFcOX-0002Hj-QZ; Sat, 21 Mar 2020 12:34:26 +0100 Received: from nanos.tec.linutronix.de (localhost [IPv6:::1]) by nanos.tec.linutronix.de (Postfix) with ESMTP id 9EB21FFBBF; Sat, 21 Mar 2020 12:34:21 +0100 (CET) Message-Id: <20200321113242.427089655@linutronix.de> User-Agent: quilt/0.65 Date: Sat, 21 Mar 2020 12:26:01 +0100 From: Thomas Gleixner To: LKML Cc: Peter Zijlstra , Ingo Molnar , Sebastian Siewior , Linus Torvalds , Joel Fernandes , Oleg Nesterov , Davidlohr Bueso , Logan Gunthorpe , Bjorn Helgaas , Kurt Schwemmer , linux-pci@vger.kernel.org, Greg Kroah-Hartman , Felipe Balbi , linux-usb@vger.kernel.org, Kalle Valo , "David S. Miller" , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, Darren Hart , Andy Shevchenko , platform-driver-x86@vger.kernel.org, Zhang Rui , "Rafael J. Wysocki" , linux-pm@vger.kernel.org, Len Brown , linux-acpi@vger.kernel.org, kbuild test robot , Nick Hu , Greentime Hu , Vincent Chen , Guo Ren , linux-csky@vger.kernel.org, Brian Cain , linux-hexagon@vger.kernel.org, Tony Luck , Fenghua Yu , linux-ia64@vger.kernel.org, Michal Simek , Michael Ellerman , Arnd Bergmann , Geoff Levand , linuxppc-dev@lists.ozlabs.org, "Paul E . McKenney" , Jonathan Corbet , Randy Dunlap , Davidlohr Bueso Subject: [patch V3 17/20] lockdep: Introduce wait-type checks References: <20200321112544.878032781@linutronix.de> MIME-Version: 1.0 Content-transfer-encoding: base64 X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1, SHORTCIRCUIT=-0.0001 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Peter Zijlstra Extend lockdep to validate lock wait-type context. The current wait-types are: LD_WAIT_FREE, /* wait free, rcu etc.. */ LD_WAIT_SPIN, /* spin loops, raw_spinlock_t etc.. */ LD_WAIT_CONFIG, /* CONFIG_PREEMPT_LOCK, spinlock_t etc.. */ LD_WAIT_SLEEP, /* sleeping locks, mutex_t etc.. */ Where lockdep validates that the current lock (the one being acquired) fits in the current wait-context (as generated by the held stack). This ensures that there is no attempt to acquire mutexes while holding spinlocks, to acquire spinlocks while holding raw_spinlocks and so on. In other words, its a more fancy might_sleep(). Obviously RCU made the entire ordeal more complex than a simple single value test because RCU can be acquired in (pretty much) any context and while it presents a context to nested locks it is not the same as it got acquired in. Therefore its necessary to split the wait_type into two values, one representing the acquire (outer) and one representing the nested context (inner). For most 'normal' locks these two are the same. [ To make static initialization easier we have the rule that: .outer == INV means .outer == .inner; because INV == 0. ] It further means that its required to find the minimal .inner of the held stack to compare against the outer of the new lock; because while 'normal' RCU presents a CONFIG type to nested locks, if it is taken while already holding a SPIN type it obviously doesn't relax the rules. Below is an example output generated by the trivial test code: raw_spin_lock(&foo); spin_lock(&bar); spin_unlock(&bar); raw_spin_unlock(&foo); [ BUG: Invalid wait context ] ----------------------------- swapper/0/1 is trying to lock: ffffc90000013f20 (&bar){....}-{3:3}, at: kernel_init+0xdb/0x187 other info that might help us debug this: 1 lock held by swapper/0/1: #0: ffffc90000013ee0 (&foo){+.+.}-{2:2}, at: kernel_init+0xd1/0x187 The way to read it is to look at the new -{n,m} part in the lock description; -{3:3} for the attempted lock, and try and match that up to the held locks, which in this case is the one: -{2,2}. This tells that the acquiring lock requires a more relaxed environment than presented by the lock stack. Currently only the normal locks and RCU are converted, the rest of the lockdep users defaults to .inner = INV which is ignored. More conversions can be done when desired. The check for spinlock_t nesting is not enabled by default. It's a separate config option for now as there are known problems which are currently addressed. The config option allows to identify these problems and to verify that the solutions found are indeed solving them. The config switch will be removed and the checks will permanently enabled once the vast majority of issues has been addressed. [ bigeasy: Move LD_WAIT_FREE,… out of CONFIG_LOCKDEP to avoid compile failure with CONFIG_DEBUG_SPINLOCK + !CONFIG_LOCKDEP] [ tglx: Add the config option ] Requested-by: Thomas Gleixner Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner --- V2: Fix the LOCKDEP=y && LOCK_PROVE=n case --- include/linux/irqflags.h | 8 ++ include/linux/lockdep.h | 71 +++++++++++++++++--- include/linux/mutex.h | 7 +- include/linux/rwlock_types.h | 6 + include/linux/rwsem.h | 6 + include/linux/sched.h | 1 include/linux/spinlock.h | 35 +++++++--- include/linux/spinlock_types.h | 24 +++++- kernel/irq/handle.c | 7 ++ kernel/locking/lockdep.c | 138 ++++++++++++++++++++++++++++++++++++++-- kernel/locking/mutex-debug.c | 2 kernel/locking/rwsem.c | 2 kernel/locking/spinlock_debug.c | 6 - kernel/rcu/update.c | 24 +++++- lib/Kconfig.debug | 17 ++++ 15 files changed, 307 insertions(+), 47 deletions(-) --- a/include/linux/irqflags.h +++ b/include/linux/irqflags.h @@ -37,7 +37,12 @@ # define trace_softirqs_enabled(p) ((p)->softirqs_enabled) # define trace_hardirq_enter() \ do { \ - current->hardirq_context++; \ + if (!current->hardirq_context++) \ + current->hardirq_threaded = 0; \ +} while (0) +# define trace_hardirq_threaded() \ +do { \ + current->hardirq_threaded = 1; \ } while (0) # define trace_hardirq_exit() \ do { \ @@ -59,6 +64,7 @@ do { \ # define trace_hardirqs_enabled(p) 0 # define trace_softirqs_enabled(p) 0 # define trace_hardirq_enter() do { } while (0) +# define trace_hardirq_threaded() do { } while (0) # define trace_hardirq_exit() do { } while (0) # define lockdep_softirq_enter() do { } while (0) # define lockdep_softirq_exit() do { } while (0) --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -21,6 +21,22 @@ extern int lock_stat; #include +enum lockdep_wait_type { + LD_WAIT_INV = 0, /* not checked, catch all */ + + LD_WAIT_FREE, /* wait free, rcu etc.. */ + LD_WAIT_SPIN, /* spin loops, raw_spinlock_t etc.. */ + +#ifdef CONFIG_PROVE_RAW_LOCK_NESTING + LD_WAIT_CONFIG, /* CONFIG_PREEMPT_LOCK, spinlock_t etc.. */ +#else + LD_WAIT_CONFIG = LD_WAIT_SPIN, +#endif + LD_WAIT_SLEEP, /* sleeping locks, mutex_t etc.. */ + + LD_WAIT_MAX, /* must be last */ +}; + #ifdef CONFIG_LOCKDEP #include @@ -111,6 +127,9 @@ struct lock_class { int name_version; const char *name; + short wait_type_inner; + short wait_type_outer; + #ifdef CONFIG_LOCK_STAT unsigned long contention_point[LOCKSTAT_POINTS]; unsigned long contending_point[LOCKSTAT_POINTS]; @@ -158,6 +177,8 @@ struct lockdep_map { struct lock_class_key *key; struct lock_class *class_cache[NR_LOCKDEP_CACHING_CLASSES]; const char *name; + short wait_type_outer; /* can be taken in this context */ + short wait_type_inner; /* presents this context */ #ifdef CONFIG_LOCK_STAT int cpu; unsigned long ip; @@ -299,8 +320,21 @@ extern void lockdep_unregister_key(struc * to lockdep: */ -extern void lockdep_init_map(struct lockdep_map *lock, const char *name, - struct lock_class_key *key, int subclass); +extern void lockdep_init_map_waits(struct lockdep_map *lock, const char *name, + struct lock_class_key *key, int subclass, short inner, short outer); + +static inline void +lockdep_init_map_wait(struct lockdep_map *lock, const char *name, + struct lock_class_key *key, int subclass, short inner) +{ + lockdep_init_map_waits(lock, name, key, subclass, inner, LD_WAIT_INV); +} + +static inline void lockdep_init_map(struct lockdep_map *lock, const char *name, + struct lock_class_key *key, int subclass) +{ + lockdep_init_map_wait(lock, name, key, subclass, LD_WAIT_INV); +} /* * Reinitialize a lock key - for cases where there is special locking or @@ -308,18 +342,29 @@ extern void lockdep_init_map(struct lock * of dependencies wrong: they are either too broad (they need a class-split) * or they are too narrow (they suffer from a false class-split): */ -#define lockdep_set_class(lock, key) \ - lockdep_init_map(&(lock)->dep_map, #key, key, 0) -#define lockdep_set_class_and_name(lock, key, name) \ - lockdep_init_map(&(lock)->dep_map, name, key, 0) -#define lockdep_set_class_and_subclass(lock, key, sub) \ - lockdep_init_map(&(lock)->dep_map, #key, key, sub) -#define lockdep_set_subclass(lock, sub) \ - lockdep_init_map(&(lock)->dep_map, #lock, \ - (lock)->dep_map.key, sub) +#define lockdep_set_class(lock, key) \ + lockdep_init_map_waits(&(lock)->dep_map, #key, key, 0, \ + (lock)->dep_map.wait_type_inner, \ + (lock)->dep_map.wait_type_outer) + +#define lockdep_set_class_and_name(lock, key, name) \ + lockdep_init_map_waits(&(lock)->dep_map, name, key, 0, \ + (lock)->dep_map.wait_type_inner, \ + (lock)->dep_map.wait_type_outer) + +#define lockdep_set_class_and_subclass(lock, key, sub) \ + lockdep_init_map_waits(&(lock)->dep_map, #key, key, sub,\ + (lock)->dep_map.wait_type_inner, \ + (lock)->dep_map.wait_type_outer) + +#define lockdep_set_subclass(lock, sub) \ + lockdep_init_map_waits(&(lock)->dep_map, #lock, (lock)->dep_map.key, sub,\ + (lock)->dep_map.wait_type_inner, \ + (lock)->dep_map.wait_type_outer) #define lockdep_set_novalidate_class(lock) \ lockdep_set_class_and_name(lock, &__lockdep_no_validate__, #lock) + /* * Compare locking classes */ @@ -432,6 +477,10 @@ static inline void lockdep_set_selftest_ # define lock_set_class(l, n, k, s, i) do { } while (0) # define lock_set_subclass(l, s, i) do { } while (0) # define lockdep_init() do { } while (0) +# define lockdep_init_map_waits(lock, name, key, sub, inner, outer) \ + do { (void)(name); (void)(key); } while (0) +# define lockdep_init_map_wait(lock, name, key, sub, inner) \ + do { (void)(name); (void)(key); } while (0) # define lockdep_init_map(lock, name, key, sub) \ do { (void)(name); (void)(key); } while (0) # define lockdep_set_class(lock, key) do { (void)(key); } while (0) --- a/include/linux/mutex.h +++ b/include/linux/mutex.h @@ -109,8 +109,11 @@ do { \ } while (0) #ifdef CONFIG_DEBUG_LOCK_ALLOC -# define __DEP_MAP_MUTEX_INITIALIZER(lockname) \ - , .dep_map = { .name = #lockname } +# define __DEP_MAP_MUTEX_INITIALIZER(lockname) \ + , .dep_map = { \ + .name = #lockname, \ + .wait_type_inner = LD_WAIT_SLEEP, \ + } #else # define __DEP_MAP_MUTEX_INITIALIZER(lockname) #endif --- a/include/linux/rwlock_types.h +++ b/include/linux/rwlock_types.h @@ -22,7 +22,11 @@ typedef struct { #define RWLOCK_MAGIC 0xdeaf1eed #ifdef CONFIG_DEBUG_LOCK_ALLOC -# define RW_DEP_MAP_INIT(lockname) .dep_map = { .name = #lockname } +# define RW_DEP_MAP_INIT(lockname) \ + .dep_map = { \ + .name = #lockname, \ + .wait_type_inner = LD_WAIT_CONFIG, \ + } #else # define RW_DEP_MAP_INIT(lockname) #endif --- a/include/linux/rwsem.h +++ b/include/linux/rwsem.h @@ -71,7 +71,11 @@ static inline int rwsem_is_locked(struct /* Common initializer macros and functions */ #ifdef CONFIG_DEBUG_LOCK_ALLOC -# define __RWSEM_DEP_MAP_INIT(lockname) , .dep_map = { .name = #lockname } +# define __RWSEM_DEP_MAP_INIT(lockname) \ + , .dep_map = { \ + .name = #lockname, \ + .wait_type_inner = LD_WAIT_SLEEP, \ + } #else # define __RWSEM_DEP_MAP_INIT(lockname) #endif --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -970,6 +970,7 @@ struct task_struct { #ifdef CONFIG_TRACE_IRQFLAGS unsigned int irq_events; + unsigned int hardirq_threaded; unsigned long hardirq_enable_ip; unsigned long hardirq_disable_ip; unsigned int hardirq_enable_event; --- a/include/linux/spinlock.h +++ b/include/linux/spinlock.h @@ -93,12 +93,13 @@ #ifdef CONFIG_DEBUG_SPINLOCK extern void __raw_spin_lock_init(raw_spinlock_t *lock, const char *name, - struct lock_class_key *key); -# define raw_spin_lock_init(lock) \ -do { \ - static struct lock_class_key __key; \ - \ - __raw_spin_lock_init((lock), #lock, &__key); \ + struct lock_class_key *key, short inner); + +# define raw_spin_lock_init(lock) \ +do { \ + static struct lock_class_key __key; \ + \ + __raw_spin_lock_init((lock), #lock, &__key, LD_WAIT_SPIN); \ } while (0) #else @@ -327,12 +328,26 @@ static __always_inline raw_spinlock_t *s return &lock->rlock; } -#define spin_lock_init(_lock) \ -do { \ - spinlock_check(_lock); \ - raw_spin_lock_init(&(_lock)->rlock); \ +#ifdef CONFIG_DEBUG_SPINLOCK + +# define spin_lock_init(lock) \ +do { \ + static struct lock_class_key __key; \ + \ + __raw_spin_lock_init(spinlock_check(lock), \ + #lock, &__key, LD_WAIT_CONFIG); \ +} while (0) + +#else + +# define spin_lock_init(_lock) \ +do { \ + spinlock_check(_lock); \ + *(_lock) = __SPIN_LOCK_UNLOCKED(_lock); \ } while (0) +#endif + static __always_inline void spin_lock(spinlock_t *lock) { raw_spin_lock(&lock->rlock); --- a/include/linux/spinlock_types.h +++ b/include/linux/spinlock_types.h @@ -33,8 +33,18 @@ typedef struct raw_spinlock { #define SPINLOCK_OWNER_INIT ((void *)-1L) #ifdef CONFIG_DEBUG_LOCK_ALLOC -# define SPIN_DEP_MAP_INIT(lockname) .dep_map = { .name = #lockname } +# define RAW_SPIN_DEP_MAP_INIT(lockname) \ + .dep_map = { \ + .name = #lockname, \ + .wait_type_inner = LD_WAIT_SPIN, \ + } +# define SPIN_DEP_MAP_INIT(lockname) \ + .dep_map = { \ + .name = #lockname, \ + .wait_type_inner = LD_WAIT_CONFIG, \ + } #else +# define RAW_SPIN_DEP_MAP_INIT(lockname) # define SPIN_DEP_MAP_INIT(lockname) #endif @@ -51,7 +61,7 @@ typedef struct raw_spinlock { { \ .raw_lock = __ARCH_SPIN_LOCK_UNLOCKED, \ SPIN_DEBUG_INIT(lockname) \ - SPIN_DEP_MAP_INIT(lockname) } + RAW_SPIN_DEP_MAP_INIT(lockname) } #define __RAW_SPIN_LOCK_UNLOCKED(lockname) \ (raw_spinlock_t) __RAW_SPIN_LOCK_INITIALIZER(lockname) @@ -72,11 +82,17 @@ typedef struct spinlock { }; } spinlock_t; +#define ___SPIN_LOCK_INITIALIZER(lockname) \ + { \ + .raw_lock = __ARCH_SPIN_LOCK_UNLOCKED, \ + SPIN_DEBUG_INIT(lockname) \ + SPIN_DEP_MAP_INIT(lockname) } + #define __SPIN_LOCK_INITIALIZER(lockname) \ - { { .rlock = __RAW_SPIN_LOCK_INITIALIZER(lockname) } } + { { .rlock = ___SPIN_LOCK_INITIALIZER(lockname) } } #define __SPIN_LOCK_UNLOCKED(lockname) \ - (spinlock_t ) __SPIN_LOCK_INITIALIZER(lockname) + (spinlock_t) __SPIN_LOCK_INITIALIZER(lockname) #define DEFINE_SPINLOCK(x) spinlock_t x = __SPIN_LOCK_UNLOCKED(x) --- a/kernel/irq/handle.c +++ b/kernel/irq/handle.c @@ -145,6 +145,13 @@ irqreturn_t __handle_irq_event_percpu(st for_each_action_of_desc(desc, action) { irqreturn_t res; + /* + * If this IRQ would be threaded under force_irqthreads, mark it so. + */ + if (irq_settings_can_thread(desc) && + !(action->flags & (IRQF_NO_THREAD | IRQF_PERCPU | IRQF_ONESHOT))) + trace_hardirq_threaded(); + trace_irq_handler_entry(irq, action); res = action->handler(irq, action->dev_id); trace_irq_handler_exit(irq, action, res); --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -653,7 +653,9 @@ static void print_lock_name(struct lock_ printk(KERN_CONT " ("); __print_lock_name(class); - printk(KERN_CONT "){%s}", usage); + printk(KERN_CONT "){%s}-{%hd:%hd}", usage, + class->wait_type_outer ?: class->wait_type_inner, + class->wait_type_inner); } static void print_lockdep_cache(struct lockdep_map *lock) @@ -1230,6 +1232,8 @@ register_lock_class(struct lockdep_map * WARN_ON_ONCE(!list_empty(&class->locks_before)); WARN_ON_ONCE(!list_empty(&class->locks_after)); class->name_version = count_matching_names(class); + class->wait_type_inner = lock->wait_type_inner; + class->wait_type_outer = lock->wait_type_outer; /* * We use RCU's safe list-add method to make * parallel walking of the hash-list safe: @@ -3682,6 +3686,113 @@ static int mark_lock(struct task_struct return ret; } +static int +print_lock_invalid_wait_context(struct task_struct *curr, + struct held_lock *hlock) +{ + if (!debug_locks_off()) + return 0; + if (debug_locks_silent) + return 0; + + pr_warn("\n"); + pr_warn("=============================\n"); + pr_warn("[ BUG: Invalid wait context ]\n"); + print_kernel_ident(); + pr_warn("-----------------------------\n"); + + pr_warn("%s/%d is trying to lock:\n", curr->comm, task_pid_nr(curr)); + print_lock(hlock); + + pr_warn("other info that might help us debug this:\n"); + lockdep_print_held_locks(curr); + + pr_warn("stack backtrace:\n"); + dump_stack(); + + return 0; +} + +/* + * Verify the wait_type context. + * + * This check validates we takes locks in the right wait-type order; that is it + * ensures that we do not take mutexes inside spinlocks and do not attempt to + * acquire spinlocks inside raw_spinlocks and the sort. + * + * The entire thing is slightly more complex because of RCU, RCU is a lock that + * can be taken from (pretty much) any context but also has constraints. + * However when taken in a stricter environment the RCU lock does not loosen + * the constraints. + * + * Therefore we must look for the strictest environment in the lock stack and + * compare that to the lock we're trying to acquire. + */ +static int check_wait_context(struct task_struct *curr, struct held_lock *next) +{ + short next_inner = hlock_class(next)->wait_type_inner; + short next_outer = hlock_class(next)->wait_type_outer; + short curr_inner; + int depth; + + if (!curr->lockdep_depth || !next_inner || next->trylock) + return 0; + + if (!next_outer) + next_outer = next_inner; + + /* + * Find start of current irq_context.. + */ + for (depth = curr->lockdep_depth - 1; depth >= 0; depth--) { + struct held_lock *prev = curr->held_locks + depth; + if (prev->irq_context != next->irq_context) + break; + } + depth++; + + /* + * Set appropriate wait type for the context; for IRQs we have to take + * into account force_irqthread as that is implied by PREEMPT_RT. + */ + if (curr->hardirq_context) { + /* + * Check if force_irqthreads will run us threaded. + */ + if (curr->hardirq_threaded) + curr_inner = LD_WAIT_CONFIG; + else + curr_inner = LD_WAIT_SPIN; + } else if (curr->softirq_context) { + /* + * Softirqs are always threaded. + */ + curr_inner = LD_WAIT_CONFIG; + } else { + curr_inner = LD_WAIT_MAX; + } + + for (; depth < curr->lockdep_depth; depth++) { + struct held_lock *prev = curr->held_locks + depth; + short prev_inner = hlock_class(prev)->wait_type_inner; + + if (prev_inner) { + /* + * We can have a bigger inner than a previous one + * when outer is smaller than inner, as with RCU. + * + * Also due to trylocks. + */ + curr_inner = min(curr_inner, prev_inner); + } + } + + if (next_outer > curr_inner) + return print_lock_invalid_wait_context(curr, next); + + return 0; +} + #else /* CONFIG_PROVE_LOCKING */ static inline int @@ -3701,13 +3812,20 @@ static inline int separate_irq_context(s return 0; } +static inline int check_wait_context(struct task_struct *curr, + struct held_lock *next) +{ + return 0; +} + #endif /* CONFIG_PROVE_LOCKING */ /* * Initialize a lock instance's lock-class mapping info: */ -void lockdep_init_map(struct lockdep_map *lock, const char *name, - struct lock_class_key *key, int subclass) +void lockdep_init_map_waits(struct lockdep_map *lock, const char *name, + struct lock_class_key *key, int subclass, + short inner, short outer) { int i; @@ -3728,6 +3846,9 @@ void lockdep_init_map(struct lockdep_map lock->name = name; + lock->wait_type_outer = outer; + lock->wait_type_inner = inner; + /* * No key, no joy, we need to hash something. */ @@ -3761,7 +3882,7 @@ void lockdep_init_map(struct lockdep_map raw_local_irq_restore(flags); } } -EXPORT_SYMBOL_GPL(lockdep_init_map); +EXPORT_SYMBOL_GPL(lockdep_init_map_waits); struct lock_class_key __lockdep_no_validate__; EXPORT_SYMBOL_GPL(__lockdep_no_validate__); @@ -3862,7 +3983,7 @@ static int __lock_acquire(struct lockdep class_idx = class - lock_classes; - if (depth) { + if (depth) { /* we're holding locks */ hlock = curr->held_locks + depth - 1; if (hlock->class_idx == class_idx && nest_lock) { if (!references) @@ -3904,6 +4025,9 @@ static int __lock_acquire(struct lockdep #endif hlock->pin_count = pin_count; + if (check_wait_context(curr, hlock)) + return 0; + /* Initialize the lock usage bit */ if (!mark_usage(curr, hlock, check)) return 0; @@ -4139,7 +4263,9 @@ static int return 0; } - lockdep_init_map(lock, name, key, 0); + lockdep_init_map_waits(lock, name, key, 0, + lock->wait_type_inner, + lock->wait_type_outer); class = register_lock_class(lock, subclass, 0); hlock->class_idx = class - lock_classes; --- a/kernel/locking/mutex-debug.c +++ b/kernel/locking/mutex-debug.c @@ -85,7 +85,7 @@ void debug_mutex_init(struct mutex *lock * Make sure we are not reinitializing a held lock: */ debug_check_no_locks_freed((void *)lock, sizeof(*lock)); - lockdep_init_map(&lock->dep_map, name, key, 0); + lockdep_init_map_wait(&lock->dep_map, name, key, 0, LD_WAIT_SLEEP); #endif lock->magic = lock; } --- a/kernel/locking/rwsem.c +++ b/kernel/locking/rwsem.c @@ -329,7 +329,7 @@ void __init_rwsem(struct rw_semaphore *s * Make sure we are not reinitializing a held semaphore: */ debug_check_no_locks_freed((void *)sem, sizeof(*sem)); - lockdep_init_map(&sem->dep_map, name, key, 0); + lockdep_init_map_wait(&sem->dep_map, name, key, 0, LD_WAIT_SLEEP); #endif #ifdef CONFIG_DEBUG_RWSEMS sem->magic = sem; --- a/kernel/locking/spinlock_debug.c +++ b/kernel/locking/spinlock_debug.c @@ -14,14 +14,14 @@ #include void __raw_spin_lock_init(raw_spinlock_t *lock, const char *name, - struct lock_class_key *key) + struct lock_class_key *key, short inner) { #ifdef CONFIG_DEBUG_LOCK_ALLOC /* * Make sure we are not reinitializing a held lock: */ debug_check_no_locks_freed((void *)lock, sizeof(*lock)); - lockdep_init_map(&lock->dep_map, name, key, 0); + lockdep_init_map_wait(&lock->dep_map, name, key, 0, inner); #endif lock->raw_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; lock->magic = SPINLOCK_MAGIC; @@ -39,7 +39,7 @@ void __rwlock_init(rwlock_t *lock, const * Make sure we are not reinitializing a held lock: */ debug_check_no_locks_freed((void *)lock, sizeof(*lock)); - lockdep_init_map(&lock->dep_map, name, key, 0); + lockdep_init_map_wait(&lock->dep_map, name, key, 0, LD_WAIT_CONFIG); #endif lock->raw_lock = (arch_rwlock_t) __ARCH_RW_LOCK_UNLOCKED; lock->magic = RWLOCK_MAGIC; --- a/kernel/rcu/update.c +++ b/kernel/rcu/update.c @@ -227,18 +227,30 @@ core_initcall(rcu_set_runtime_mode); #ifdef CONFIG_DEBUG_LOCK_ALLOC static struct lock_class_key rcu_lock_key; -struct lockdep_map rcu_lock_map = - STATIC_LOCKDEP_MAP_INIT("rcu_read_lock", &rcu_lock_key); +struct lockdep_map rcu_lock_map = { + .name = "rcu_read_lock", + .key = &rcu_lock_key, + .wait_type_outer = LD_WAIT_FREE, + .wait_type_inner = LD_WAIT_CONFIG, /* XXX PREEMPT_RCU ? */ +}; EXPORT_SYMBOL_GPL(rcu_lock_map); static struct lock_class_key rcu_bh_lock_key; -struct lockdep_map rcu_bh_lock_map = - STATIC_LOCKDEP_MAP_INIT("rcu_read_lock_bh", &rcu_bh_lock_key); +struct lockdep_map rcu_bh_lock_map = { + .name = "rcu_read_lock_bh", + .key = &rcu_bh_lock_key, + .wait_type_outer = LD_WAIT_FREE, + .wait_type_inner = LD_WAIT_CONFIG, /* PREEMPT_LOCK also makes BH preemptible */ +}; EXPORT_SYMBOL_GPL(rcu_bh_lock_map); static struct lock_class_key rcu_sched_lock_key; -struct lockdep_map rcu_sched_lock_map = - STATIC_LOCKDEP_MAP_INIT("rcu_read_lock_sched", &rcu_sched_lock_key); +struct lockdep_map rcu_sched_lock_map = { + .name = "rcu_read_lock_sched", + .key = &rcu_sched_lock_key, + .wait_type_outer = LD_WAIT_FREE, + .wait_type_inner = LD_WAIT_SPIN, +}; EXPORT_SYMBOL_GPL(rcu_sched_lock_map); static struct lock_class_key rcu_callback_key; --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1086,6 +1086,23 @@ config PROVE_LOCKING For more details, see Documentation/locking/lockdep-design.rst. +config PROVE_RAW_LOCK_NESTING + bool "Enable raw_spinlock - spinlock nesting checks" + depends on PROVE_LOCKING + default n + help + Enable the raw_spinlock vs. spinlock nesting checks which ensure + that the lock nesting rules for PREEMPT_RT enabled kernels are + not violated. + + NOTE: There are known nesting problems. So if you enable this + option expect lockdep splats until these problems have been fully + addressed which is work in progress. This config switch allows to + identify and analyze these problems. It will be removed and the + check permanentely enabled once the main issues have been fixed. + + If unsure, select N. + config LOCK_STAT bool "Lock usage statistics" depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT From patchwork Sat Mar 21 11:26:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 222112 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 03DE4C4332B for ; Sat, 21 Mar 2020 11:35:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CD78920722 for ; Sat, 21 Mar 2020 11:35:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728679AbgCULfB (ORCPT ); Sat, 21 Mar 2020 07:35:01 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:38487 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728492AbgCULe5 (ORCPT ); Sat, 21 Mar 2020 07:34:57 -0400 Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jFcOd-0002LQ-Fh; Sat, 21 Mar 2020 12:34:31 +0100 Received: from nanos.tec.linutronix.de (localhost [IPv6:::1]) by nanos.tec.linutronix.de (Postfix) with ESMTP id 2B9001040CB; Sat, 21 Mar 2020 12:34:22 +0100 (CET) Message-Id: <20200321113242.643576700@linutronix.de> User-Agent: quilt/0.65 Date: Sat, 21 Mar 2020 12:26:03 +0100 From: Thomas Gleixner To: LKML Cc: Peter Zijlstra , Ingo Molnar , Sebastian Siewior , Linus Torvalds , Joel Fernandes , Oleg Nesterov , Davidlohr Bueso , Logan Gunthorpe , Bjorn Helgaas , Kurt Schwemmer , linux-pci@vger.kernel.org, Greg Kroah-Hartman , Felipe Balbi , linux-usb@vger.kernel.org, Kalle Valo , "David S. Miller" , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, Darren Hart , Andy Shevchenko , platform-driver-x86@vger.kernel.org, Zhang Rui , "Rafael J. Wysocki" , linux-pm@vger.kernel.org, Len Brown , linux-acpi@vger.kernel.org, kbuild test robot , Nick Hu , Greentime Hu , Vincent Chen , Guo Ren , linux-csky@vger.kernel.org, Brian Cain , linux-hexagon@vger.kernel.org, Tony Luck , Fenghua Yu , linux-ia64@vger.kernel.org, Michal Simek , Michael Ellerman , Arnd Bergmann , Geoff Levand , linuxppc-dev@lists.ozlabs.org, "Paul E . McKenney" , Jonathan Corbet , Randy Dunlap , Davidlohr Bueso Subject: [patch V3 19/20] lockdep: Annotate irq_work References: <20200321112544.878032781@linutronix.de> MIME-Version: 1.0 Content-transfer-encoding: 8-bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1, SHORTCIRCUIT=-0.0001 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Sebastian Andrzej Siewior Mark irq_work items with IRQ_WORK_HARD_IRQ which should be invoked in hardirq context even on PREEMPT_RT. IRQ_WORK without this flag will be invoked in softirq context on PREEMPT_RT. Set ->irq_config to 1 for the IRQ_WORK items which are invoked in softirq context so lockdep knows that these can safely acquire a spinlock_t. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner --- include/linux/irq_work.h | 2 ++ include/linux/irqflags.h | 13 +++++++++++++ kernel/irq_work.c | 2 ++ kernel/rcu/tree.c | 1 + kernel/time/tick-sched.c | 1 + 5 files changed, 19 insertions(+) --- a/include/linux/irq_work.h +++ b/include/linux/irq_work.h @@ -18,6 +18,8 @@ /* Doesn't want IPI, wait for tick: */ #define IRQ_WORK_LAZY BIT(2) +/* Run hard IRQ context, even on RT */ +#define IRQ_WORK_HARD_IRQ BIT(3) #define IRQ_WORK_CLAIMED (IRQ_WORK_PENDING | IRQ_WORK_BUSY) --- a/include/linux/irqflags.h +++ b/include/linux/irqflags.h @@ -69,6 +69,17 @@ do { \ current->irq_config = 0; \ } while (0) +# define lockdep_irq_work_enter(__work) \ + do { \ + if (!(atomic_read(&__work->flags) & IRQ_WORK_HARD_IRQ))\ + current->irq_config = 1; \ + } while (0) +# define lockdep_irq_work_exit(__work) \ + do { \ + if (!(atomic_read(&__work->flags) & IRQ_WORK_HARD_IRQ))\ + current->irq_config = 0; \ + } while (0) + #else # define trace_hardirqs_on() do { } while (0) # define trace_hardirqs_off() do { } while (0) @@ -83,6 +94,8 @@ do { \ # define lockdep_softirq_exit() do { } while (0) # define lockdep_hrtimer_enter(__hrtimer) do { } while (0) # define lockdep_hrtimer_exit(__hrtimer) do { } while (0) +# define lockdep_irq_work_enter(__work) do { } while (0) +# define lockdep_irq_work_exit(__work) do { } while (0) #endif #if defined(CONFIG_IRQSOFF_TRACER) || \ --- a/kernel/irq_work.c +++ b/kernel/irq_work.c @@ -153,7 +153,9 @@ static void irq_work_run_list(struct lli */ flags = atomic_fetch_andnot(IRQ_WORK_PENDING, &work->flags); + lockdep_irq_work_enter(work); work->func(work); + lockdep_irq_work_exit(work); /* * Clear the BUSY bit and return to the free state if * no-one else claimed it meanwhile. --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -1113,6 +1113,7 @@ static int rcu_implicit_dynticks_qs(stru !rdp->rcu_iw_pending && rdp->rcu_iw_gp_seq != rnp->gp_seq && (rnp->ffmask & rdp->grpmask)) { init_irq_work(&rdp->rcu_iw, rcu_iw_handler); + atomic_set(&rdp->rcu_iw.flags, IRQ_WORK_HARD_IRQ); rdp->rcu_iw_pending = true; rdp->rcu_iw_gp_seq = rnp->gp_seq; irq_work_queue_on(&rdp->rcu_iw, rdp->cpu); --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -245,6 +245,7 @@ static void nohz_full_kick_func(struct i static DEFINE_PER_CPU(struct irq_work, nohz_full_kick_work) = { .func = nohz_full_kick_func, + .flags = ATOMIC_INIT(IRQ_WORK_HARD_IRQ), }; /* From patchwork Sat Mar 21 11:26:04 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 222103 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BE1DCC4332D for ; Sat, 21 Mar 2020 11:37:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A03F320658 for ; Sat, 21 Mar 2020 11:37:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728537AbgCULez (ORCPT ); Sat, 21 Mar 2020 07:34:55 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:38423 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726652AbgCULex (ORCPT ); Sat, 21 Mar 2020 07:34:53 -0400 Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jFcOZ-0002Re-66; Sat, 21 Mar 2020 12:34:27 +0100 Received: from nanos.tec.linutronix.de (localhost [IPv6:::1]) by nanos.tec.linutronix.de (Postfix) with ESMTP id 692651040CC; Sat, 21 Mar 2020 12:34:22 +0100 (CET) Message-Id: <20200321113242.751182723@linutronix.de> User-Agent: quilt/0.65 Date: Sat, 21 Mar 2020 12:26:04 +0100 From: Thomas Gleixner To: LKML Cc: Peter Zijlstra , Ingo Molnar , Sebastian Siewior , Linus Torvalds , Joel Fernandes , Oleg Nesterov , Davidlohr Bueso , Logan Gunthorpe , Bjorn Helgaas , Kurt Schwemmer , linux-pci@vger.kernel.org, Greg Kroah-Hartman , Felipe Balbi , linux-usb@vger.kernel.org, Kalle Valo , "David S. Miller" , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, Darren Hart , Andy Shevchenko , platform-driver-x86@vger.kernel.org, Zhang Rui , "Rafael J. Wysocki" , linux-pm@vger.kernel.org, Len Brown , linux-acpi@vger.kernel.org, kbuild test robot , Nick Hu , Greentime Hu , Vincent Chen , Guo Ren , linux-csky@vger.kernel.org, Brian Cain , linux-hexagon@vger.kernel.org, Tony Luck , Fenghua Yu , linux-ia64@vger.kernel.org, Michal Simek , Michael Ellerman , Arnd Bergmann , Geoff Levand , linuxppc-dev@lists.ozlabs.org, "Paul E . McKenney" , Jonathan Corbet , Randy Dunlap , Davidlohr Bueso Subject: [patch V3 20/20] lockdep: Add posixtimer context tracing bits References: <20200321112544.878032781@linutronix.de> MIME-Version: 1.0 Content-transfer-encoding: 8-bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1, SHORTCIRCUIT=-0.0001 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Sebastian Andrzej Siewior Splitting run_posix_cpu_timers() into two parts is work in progress which is stuck on other entry code related problems. The heavy lifting which involves locking of sighand lock will be moved into task context so the necessary execution time is burdened on the task and not on interrupt context. Until this work completes lockdep with the spinlock nesting rules enabled would emit warnings for this known context. Prevent it by setting "->irq_config = 1" for the invocation of run_posix_cpu_timers() so lockdep does not complain when sighand lock is acquried. This will be removed once the split is completed. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner --- include/linux/irqflags.h | 12 ++++++++++++ kernel/time/posix-cpu-timers.c | 6 +++++- 2 files changed, 17 insertions(+), 1 deletion(-) --- a/include/linux/irqflags.h +++ b/include/linux/irqflags.h @@ -69,6 +69,16 @@ do { \ current->irq_config = 0; \ } while (0) +# define lockdep_posixtimer_enter() \ + do { \ + current->irq_config = 1; \ + } while (0) + +# define lockdep_posixtimer_exit() \ + do { \ + current->irq_config = 0; \ + } while (0) + # define lockdep_irq_work_enter(__work) \ do { \ if (!(atomic_read(&__work->flags) & IRQ_WORK_HARD_IRQ))\ @@ -94,6 +104,8 @@ do { \ # define lockdep_softirq_exit() do { } while (0) # define lockdep_hrtimer_enter(__hrtimer) do { } while (0) # define lockdep_hrtimer_exit(__hrtimer) do { } while (0) +# define lockdep_posixtimer_enter() do { } while (0) +# define lockdep_posixtimer_exit() do { } while (0) # define lockdep_irq_work_enter(__work) do { } while (0) # define lockdep_irq_work_exit(__work) do { } while (0) #endif --- a/kernel/time/posix-cpu-timers.c +++ b/kernel/time/posix-cpu-timers.c @@ -1126,8 +1126,11 @@ void run_posix_cpu_timers(void) if (!fastpath_timer_check(tsk)) return; - if (!lock_task_sighand(tsk, &flags)) + lockdep_posixtimer_enter(); + if (!lock_task_sighand(tsk, &flags)) { + lockdep_posixtimer_exit(); return; + } /* * Here we take off tsk->signal->cpu_timers[N] and * tsk->cpu_timers[N] all the timers that are firing, and @@ -1169,6 +1172,7 @@ void run_posix_cpu_timers(void) cpu_timer_fire(timer); spin_unlock(&timer->it_lock); } + lockdep_posixtimer_exit(); } /*