From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi1-f181.google.com (mail-oi1-f181.google.com [209.85.167.181]) by mail19.linbit.com (LINBIT Mail Daemon) with ESMTP id D126B4210DE for ; Fri, 4 Nov 2022 20:22:35 +0100 (CET) Received: by mail-oi1-f181.google.com with SMTP id n186so6164456oih.7 for ; Fri, 04 Nov 2022 12:22:35 -0700 (PDT) Sender: Guenter Roeck Date: Fri, 4 Nov 2022 12:22:32 -0700 From: Guenter Roeck To: Steven Rostedt Message-ID: <20221104192232.GA2520396@roeck-us.net> References: <20221104054053.431922658@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221104054053.431922658@goodmis.org> Cc: alsa-devel@alsa-project.org, linux-staging@lists.linux.dev, linux-doc@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, Thomas Gleixner , linux-leds@vger.kernel.org, drbd-dev@lists.linbit.com, linux-s390@vger.kernel.org, linux-nilfs@vger.kernel.org, linux-scsi@vger.kernel.org, linux-sh@vger.kernel.org, linux-atm-general@lists.sourceforge.net, linux-afs@lists.infradead.org, lvs-devel@vger.kernel.org, linux-acpi@vger.kernel.org, coreteam@netfilter.org, intel-wired-lan@lists.osuosl.org, linux-input@vger.kernel.org, tipc-discussion@lists.sourceforge.net, linux-ext4@vger.kernel.org, linux-media@vger.kernel.org, bridge@lists.linux-foundation.org, linux-pm@vger.kernel.org, intel-gfx@lists.freedesktop.org, rcu@vger.kernel.org, cgroups@vger.kernel.org, openipmi-developer@lists.sourceforge.net, Anna-Maria Gleixner , linux-edac@vger.kernel.org, linux-block@vger.kernel.org, linux-nfs@vger.kernel.org, linux-parisc@vger.kernel.org, Stephen Boyd , netdev@vger.kernel.org, linux-usb@vger.kernel.org, linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org, linux-bluetooth@vger.kernel.org, netfilter-devel@vger.kernel.org, Andrew Morton , Linus Torvalds Subject: Re: [Drbd-dev] [RFC][PATCH v3 00/33] timers: Use timer_shutdown*() before freeing timers List-Id: "*Coordination* of development, patches, contributions -- *Questions* \(even to developers\) go to drbd-user, please." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, Nov 04, 2022 at 01:40:53AM -0400, Steven Rostedt wrote: > > Back in April, I posted an RFC patch set to help mitigate a common issue > where a timer gets armed just before it is freed, and when the timer > goes off, it crashes in the timer code without any evidence of who the > culprit was. I got side tracked and never finished up on that patch set. > Since this type of crash is still our #1 crash we are seeing in the field, > it has become a priority again to finish it. > > This is v3 of that patch set. Thomas Gleixner posted an untested version > that makes timer->function NULL as the flag that it is shutdown. I took that > code, tested it (fixed it up), added more comments, and changed the > name to timer_shutdown_sync(). I also converted it to use WARN_ON_ONCE() > instead of just WARN_ON() as Linus asked for. > Unfortunately the renaming caused some symbol conflicts. Global definition: timer_shutdown File Line 0 time.c 93 static inline void timer_shutdown(struct clock_event_device *evt) 1 arm_arch_timer.c 690 static __always_inline int timer_shutdown(const int access, 2 timer-fttmr010.c 105 int (*timer_shutdown)(struct clock_event_device *evt); 3 timer-sp804.c 158 static inline void timer_shutdown(struct clock_event_device *evt) 4 timer.h 239 static inline int timer_shutdown(struct timer_list *timer) Guenter