From mboxrd@z Thu Jan 1 00:00:00 1970 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DD2BDC41535 for ; Sat, 5 Nov 2022 21:45:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230131AbiKEVpv (ORCPT ); Sat, 5 Nov 2022 17:45:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38750 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229756AbiKEVps (ORCPT ); Sat, 5 Nov 2022 17:45:48 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 024B712AE7; Sat, 5 Nov 2022 14:45:46 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 89B2B60B98; Sat, 5 Nov 2022 21:45:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 74BDDC433D6; Sat, 5 Nov 2022 21:45:44 +0000 (UTC) Date: Sat, 5 Nov 2022 17:45:42 -0400 From: Steven Rostedt To: Linus Torvalds Cc: "Jason A. Donenfeld" , linux-kernel@vger.kernel.org, Thomas Gleixner , Stephen Boyd , Guenter Roeck , Anna-Maria Gleixner , Andrew Morton , rcu@vger.kernel.org, linux-doc@vger.kernel.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, linux-edac@vger.kernel.org, cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-acpi@vger.kernel.org, linux-atm-general@lists.sourceforge.net, netdev@vger.kernel.org, linux-pm@vger.kernel.org, drbd-dev@lists.linbit.com, linux-bluetooth@vger.kernel.org, openipmi-developer@lists.sourceforge.net, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, intel-gfx@lists.freedesktop.org, linux-input@vger.kernel.org, linux-parisc@vger.kernel.org, linux-leds@vger.kernel.org, intel-wired-lan@lists.osuosl.org, linux-usb@vger.kernel.org, linux-wireless@vger.kernel.org, linux-scsi@vger.kernel.org, linux-staging@lists.linux.dev, linux-ext4@vger.kernel.org, linux-nilfs@vger.kernel.org, bridge@lists.linux-foundation.org, netfilter-devel@vger.kernel.org, coreteam@netfilter.org, lvs-devel@vger.kernel.org, linux-afs@lists.infradead.org, linux-nfs@vger.kernel.org, tipc-discussion@lists.sourceforge.net, alsa-devel@alsa-project.org Subject: Re: [PATCH v4a 00/38] timers: Use timer_shutdown*() before freeing timers Message-ID: <20221105174542.21bd7e86@rorschach.local.home> In-Reply-To: References: <20221105060024.598488967@goodmis.org> <20221105123642.596371c7@rorschach.local.home> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org On Sat, 5 Nov 2022 14:13:14 -0700 Linus Torvalds wrote: > And trying "when != ptr->timer" actually does the right thing in that > it gets rid of the case where the timer is modified outside of the > del_timer() case, *but* it also causes odd other changes to the > output. > > Look at what it generates for that > > drivers/media/usb/pvrusb2/pvrusb2-hdw.c > > file, which finds a lot of triggers with the "when != ptr->timer", > but only does one without it. I added an expression, and it appears to work: At least for this case. @@ expression E; identifier ptr, timer, rfield, slab; @@ ( - del_timer(&ptr->timer); + timer_shutdown(&ptr->timer); | - del_timer_sync(&ptr->timer); + timer_shutdown_sync(&ptr->timer); ) ... when != ptr->timer.function = E; ( kfree_rcu(ptr, rfield); | kmem_cache_free(slab, ptr); | kfree(ptr); ) Now I need to add return and goto cases here. -- Steve