From patchwork Wed Nov 23 20:18:39 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 628450 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 8FF8FC4332F for ; Wed, 23 Nov 2022 20:20:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239683AbiKWUUl (ORCPT ); Wed, 23 Nov 2022 15:20:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43630 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238765AbiKWUUN (ORCPT ); Wed, 23 Nov 2022 15:20:13 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B5094AB0C0; Wed, 23 Nov 2022 12:18:42 -0800 (PST) Message-ID: <20221123201624.769128888@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1669234719; 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=eCimoLuvktZLfB1uOtjhcgzwdNyr85jFqFSGejnZxME=; b=CD7L6ldoiPUtWAt54rxE0W37G6sMJzvkUpu0CzeC2d09LvqtPSkoD8xTrpbN5utui5RVLx wikpVoqxmsFwfAl3lvMMOY1yfmJKHCsKaMzvG7n5iAYhOGJddhR3f86fKB8R1c0CUJI8hZ 8NcI0p6p+XU8OV6yu98t/zR82Az7tIL1HSZQQU0UL/ki1z9vcaCGW2JY17u2Tz07o3XRIy lnxNbLkht3CJ8veszSeR6zJtFkKsvSz31nUoMWwE3MPgmfxY1THUAqdN32kNeo1OzKdTjL D9eK+z9nRVonc0WfshhEqTrBkLyLzWJkBQdm7QXaqomEGrNjcxkcxxTUYew4Og== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1669234719; 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=eCimoLuvktZLfB1uOtjhcgzwdNyr85jFqFSGejnZxME=; b=BahGPyyTQcd2X5VjiZl2zwqvSBRDAeFNKqDQfbrS+8G+gM7ADytoXTQqiaPoAGO5628h/R mcu8C9E6HfyYMqCA== 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, Jacob Keller Subject: [patch V3 06/17] timers: Replace BUG_ON()s References: <20221123201306.823305113@linutronix.de> MIME-Version: 1.0 Date: Wed, 23 Nov 2022 21:18:39 +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 Reviewed-by: Jacob Keller --- 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);