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 6C097C27C7C for ; Fri, 20 Jan 2023 13:44:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229980AbjATNoy (ORCPT ); Fri, 20 Jan 2023 08:44:54 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52224 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229459AbjATNou (ORCPT ); Fri, 20 Jan 2023 08:44:50 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 924E86CCF2; Fri, 20 Jan 2023 05:44:49 -0800 (PST) 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 2CFDA61F50; Fri, 20 Jan 2023 13:44:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0A2F3C433EF; Fri, 20 Jan 2023 13:44:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1674222288; bh=Vx0Ly4/3FYSIZHj8WshPhEigMtjpQJssbX6/OvRC0Vs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=uhcNop+tkx4/VgWHWf2r7USeTlryrpu4HsZOfu1C7MIAzxx8Z0XZvoKeej1TQk+b6 yLs5DpWsgsZRryoNWPjnQ+SyTZzDcdUrkCtK1ehSEvS1Avws+S9Qa3ihwX6P21gMCt A2L7qKgmYb5MQZmFAQ32FKHbITcI4wsesDTbPn6A= Date: Fri, 20 Jan 2023 14:44:46 +0100 From: Greg Kroah-Hartman To: Joel Fernandes Cc: linux-kernel@vger.kernel.org, Frederic Weisbecker , "Paul E. McKenney" , Zhouyi Zhou , Will Deacon , Marc Zyngier , rcu , Frederic Weisbecker , Ingo Molnar , "Rafael J. Wysocki" , Thomas Gleixner Subject: Re: [PATCH] tick/nohz: Fix cpu_is_hotpluggable() by checking with nohz subsystem Message-ID: References: <37171A49-82E9-4008-9B5B-1CEEDC9B653E@joelfernandes.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <37171A49-82E9-4008-9B5B-1CEEDC9B653E@joelfernandes.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jan 20, 2023 at 08:32:30AM -0500, Joel Fernandes wrote: > > > > On Jan 20, 2023, at 2:05 AM, Greg Kroah-Hartman wrote: > > > > On Thu, Jan 19, 2023 at 08:44:35PM +0000, Joel Fernandes (Google) wrote: > >> For CONFIG_NO_HZ_FULL systems, the tick_do_timer_cpu cannot be offlined. > >> However, cpu_is_hotpluggable() still returns true for those CPUs. This causes > >> torture tests that do offlining to end up trying to offline this CPU causing > >> test failures. Such failure happens on all architectures. > >> > >> Fix it by asking the opinion of the nohz subsystem on whether the CPU can > >> be hotplugged. > >> > >> [ Apply Frederic Weisbecker feedback on refactoring tick_nohz_cpu_down(). ] > >> > >> Cc: Frederic Weisbecker > >> Cc: "Paul E. McKenney" > >> Cc: Zhouyi Zhou > >> Cc: Will Deacon > >> Cc: Marc Zyngier > >> Cc: rcu > >> Fixes: 2987557f52b9 ("driver-core/cpu: Expose hotpluggability to the rest of the kernel") > >> Signed-off-by: Joel Fernandes (Google) > > > > Also want to cc: stable on the patch? > > Oh sure, sorry. For some reason I thought Sasha and your AI scripts > were looking at the Linux-kernel list as well. Or are they, and a Cc > to stable is just to be doubly sure? As per the rules we have had for the last 15+ years, always add a cc: stable to be sure that the patch will be considered for stable releases. If not, you are on you own and sometimes we might notice it, others not. See: https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html for the details. thanks, greg k-h