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 X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 069CCC4743F for ; Mon, 7 Jun 2021 07:13:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E359261185 for ; Mon, 7 Jun 2021 07:13:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230241AbhFGHPH (ORCPT ); Mon, 7 Jun 2021 03:15:07 -0400 Received: from smtp-out2.suse.de ([195.135.220.29]:56142 "EHLO smtp-out2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229436AbhFGHPG (ORCPT ); Mon, 7 Jun 2021 03:15:06 -0400 Received: from relay2.suse.de (unknown [149.44.160.134]) by smtp-out2.suse.de (Postfix) with ESMTP id 5A6BA1FD30; Mon, 7 Jun 2021 07:13:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1623049994; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=aHCqXBT+MGYC5mZhyDA+3mFlUNAnp8q9dvOMZ0W9WJI=; b=FlrNGLi8rvCIgp3RXrUnbL/05DETZ2bF3dEHIA+DN94ch7wjF5vL7FdpRos6vtJOgST1rs 5qKgfoujUhlC/EMQ/dbmZ/DsiWVhIl+3+4RU5YXToA0+IrzUNRUeVLZghFhc7DLV36gaU1 MXpM30mc+1epGbFxPHg4TCJo9acE9S0= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1623049994; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=aHCqXBT+MGYC5mZhyDA+3mFlUNAnp8q9dvOMZ0W9WJI=; b=PGcoBXZRnAg/FOkJ5qNCYz+Nog6xfzFiRAesLCWwZmrhYfOKBmR7heRqtPt7GLEK2MWjl4 xYMn3vVGnmjk7iCA== Received: from alsa1.suse.de (alsa1.suse.de [10.160.4.42]) by relay2.suse.de (Postfix) with ESMTP id 2FEFDA3B87; Mon, 7 Jun 2021 07:13:14 +0000 (UTC) Date: Mon, 07 Jun 2021 09:13:14 +0200 Message-ID: From: Takashi Iwai To: Viresh Kumar Cc: kyle.meyer@hpe.com, rjw@rjwysocki.net, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, linux-acpi@vger.kernel.org, Takashi Iwai Subject: Re: [PATCH] acpi-cpufreq: Skip cleanup if initialization didn't occur In-Reply-To: <20210607032550.qdnl2sxnny42rtwa@vireshk-i7> References: <20210604170500.46875-1-kyle.meyer@hpe.com> <20210607032550.qdnl2sxnny42rtwa@vireshk-i7> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL/10.8 Emacs/25.3 (x86_64-suse-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 07 Jun 2021 05:25:50 +0200, Viresh Kumar wrote: > > On 04-06-21, 12:05, kyle.meyer@hpe.com wrote: > > From: Kyle Meyer > > > > acpi-cpufreq is loaded without performing initialization when a cpufreq > > driver exists. > > > > If initialization didn't occur then skip cleanup in acpi_cpufreq_exit(). > > This prevents unnecessary freeing and unregistering when the module is > > unloaded. > > > > Reported-by: Takashi Iwai > > Signed-off-by: Kyle Meyer > > --- > > drivers/cpufreq/acpi-cpufreq.c | 11 +++++++++++ > > 1 file changed, 11 insertions(+) > > > > diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c > > index 7e7450453714..8d425f14c267 100644 > > --- a/drivers/cpufreq/acpi-cpufreq.c > > +++ b/drivers/cpufreq/acpi-cpufreq.c > > @@ -1042,8 +1042,19 @@ static int __init acpi_cpufreq_init(void) > > > > static void __exit acpi_cpufreq_exit(void) > > { > > + const char *current_driver; > > + > > pr_debug("%s\n", __func__); > > > > + /* > > + * If another cpufreq_driver was loaded, preventing acpi-cpufreq from > > + * registering, there's no need to unregister it. > > + */ > > + current_driver = cpufreq_get_current_driver(); > > + if (!current_driver || > > + strncmp(current_driver, acpi_cpufreq_driver.name, strlen(acpi_cpufreq_driver.name))) > > + return; > > + > > acpi_cpufreq_boost_exit(); > > > > cpufreq_unregister_driver(&acpi_cpufreq_driver); > > Looks like some misunderstanding here, this shouldn't happen. If > initialization didn't occur, then exit shall never be called. The missing key information is that it's a fix for the recent change for 5.14, i.e. Fixes: c1d6d2fd2f64 ("cpufreq: acpi-cpufreq: Skip initialization if cpufreq driver is present") The change made the module left even if it exits before registering the cpufreq driver object. Takashi