From patchwork Tue Nov 22 17:44:53 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 13052613 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 5BB24C433FE for ; Tue, 22 Nov 2022 17:45:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234426AbiKVRpa (ORCPT ); Tue, 22 Nov 2022 12:45:30 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59262 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233498AbiKVRpS (ORCPT ); Tue, 22 Nov 2022 12:45:18 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D382B65F0; Tue, 22 Nov 2022 09:44:55 -0800 (PST) Message-ID: <20221122173648.442211558@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1669139094; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=idu06WOJve3djJAPc7BtVv8nMt9NfLYdyVD3CA4QRcI=; b=ZYvUvpFjYwMgT90NqNqJBAbZfVeA9cpTH1StBL/7CEhaN1Eq0Dd2LV2hvVdA6iYh+VHsI8 cpetnVScKynrAMAhftuD15H4UgmFS2eeZsYfUBJkiQy59KnMQmBDDla7WfWPkkqjz3+REB ynTYR1170fjBoPjitNb3xtKOD6uqeQcXWuKV2Cbb/3ekBYOQH9tEBfbF8H48YGtHWrP9ZS aTw+sTG3Xd4vEM8RtxB+VpLpwlIpeu3xCPoRIuidkXwpPqtJ5oCsZK9I5wtY/He7YMMDrY ldAn5GL9cQtjsXDUINMmI9pQWCTsQ+xJv1Bz94gSOeN+XYT9eDeu+XQsTOrXKg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1669139094; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=idu06WOJve3djJAPc7BtVv8nMt9NfLYdyVD3CA4QRcI=; b=Uqc/eiX6vOdogzxNUrmROEQVX+aY9FcykUIR2w245p5xg67epAVFF2IuQAObckDw+Tdtch s+j0sOk47YO1grDA== From: Thomas Gleixner To: LKML Cc: Linus Torvalds , Steven Rostedt , Anna-Maria Behnsen , Peter Zijlstra , Stephen Boyd , Guenter Roeck , Andrew Morton , Julia Lawall , Arnd Bergmann , Viresh Kumar , Marc Zyngier , Marcel Holtmann , Johan Hedberg , Luiz Augusto von Dentz , linux-bluetooth@vger.kernel.org, "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , netdev@vger.kernel.org Subject: [patch V2 06/17] timers: Replace BUG_ON()s References: <20221122171312.191765396@linutronix.de> MIME-Version: 1.0 Date: Tue, 22 Nov 2022 18:44:53 +0100 (CET) Precedence: bulk List-ID: X-Mailing-List: linux-bluetooth@vger.kernel.org The timer code still has a few BUG_ON()s left which are crashing the kernel in situations where it still can recover or simply refuse to take an action. Remove the one in the hotplug callback which checks for the CPU being offline. If that happens then the whole hotplug machinery will explode in colourful ways. Replace the rest with WARN_ON_ONCE() and conditional returns where appropriate. Signed-off-by: Thomas Gleixner Tested-by: Guenter Roeck --- kernel/time/timer.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) --- a/kernel/time/timer.c +++ b/kernel/time/timer.c @@ -1193,7 +1193,8 @@ EXPORT_SYMBOL(timer_reduce); */ void add_timer(struct timer_list *timer) { - BUG_ON(timer_pending(timer)); + if (WARN_ON_ONCE(timer_pending(timer))) + return; __mod_timer(timer, timer->expires, MOD_TIMER_NOTPENDING); } EXPORT_SYMBOL(add_timer); @@ -1210,7 +1211,8 @@ void add_timer_on(struct timer_list *tim struct timer_base *new_base, *base; unsigned long flags; - BUG_ON(timer_pending(timer) || !timer->function); + if (WARN_ON_ONCE(timer_pending(timer) || !timer->function)) + return; new_base = get_timer_cpu_base(timer->flags, cpu); @@ -2017,8 +2019,6 @@ int timers_dead_cpu(unsigned int cpu) struct timer_base *new_base; int b, i; - BUG_ON(cpu_online(cpu)); - for (b = 0; b < NR_BASES; b++) { old_base = per_cpu_ptr(&timer_bases[b], cpu); new_base = get_cpu_ptr(&timer_bases[b]); @@ -2035,7 +2035,8 @@ int timers_dead_cpu(unsigned int cpu) */ forward_timer_base(new_base); - BUG_ON(old_base->running_timer); + WARN_ON_ONCE(old_base->running_timer); + old_base->running_timer = NULL; for (i = 0; i < WHEEL_SIZE; i++) migrate_timer_list(new_base, old_base->vectors + i);