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 70C44C433EF for ; Tue, 5 Jul 2022 10:38:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232186AbiGEKio (ORCPT ); Tue, 5 Jul 2022 06:38:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60726 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230421AbiGEKim (ORCPT ); Tue, 5 Jul 2022 06:38:42 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9B0B2C24; Tue, 5 Jul 2022 03:38:41 -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 38D6761A3D; Tue, 5 Jul 2022 10:38:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 18CA8C341C7; Tue, 5 Jul 2022 10:38:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1657017520; bh=z1GqxMIwtmun/u1tj/pwcRt5NAZl8SZdFgsjlbLxAlk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=rJKQ7WAmD2TzLUHrHcm77qh5JTv1SeM/6ZN4w/jjFPT8kBLaJayUYai8Y/0mPsrqv 4tc9uz183UNWDGkjq1pM8BUIqx49/xTprWdqJu6abkV9eR0jMVj6gQLMxEG3G6et9E ljmGLgZ2uofbAZqt78npuydbsDyZTZ2qJeWldV90= Date: Tue, 5 Jul 2022 12:38:37 +0200 From: Greg Kroah-Hartman To: Hsin-Yi Wang Cc: "Rafael J . Wysocki" , Kevin Hilman , Ulf Hansson , Len Brown , Pavel Machek , Thierry Strudel , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, AngeloGioacchino Del Regno , Pin-yen Lin Subject: Re: [PATCH] PM: domains: Ensure genpd_debugfs_dir exists before remove Message-ID: References: <20220705094946.827697-1-hsinyi@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220705094946.827697-1-hsinyi@chromium.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 05, 2022 at 05:49:47PM +0800, Hsin-Yi Wang wrote: > genpd_debug_remove() may be indirectly called from others while > genpd_debugfs_dir is not yet set. Make sure genpd_debugfs_dir exists > before remove the sub components, otherwise components under > /sys/kernel/debug may be accidentally removed. > > Fixes: 718072ceb211 ("PM: domains: create debugfs nodes when adding power domains") > Signed-off-by: Hsin-Yi Wang > --- > An example: > scpsys_probe() in drivers/soc/mediatek/mtk-pm-domains.c indirectly calls > genpd_debug_remove() on probe fail, causing /sys/kernel/debug/usb to be > removed. > --- > drivers/base/power/domain.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c > index 3e86772d5fac5..5a2e0232862e0 100644 > --- a/drivers/base/power/domain.c > +++ b/drivers/base/power/domain.c > @@ -222,6 +222,9 @@ static void genpd_debug_remove(struct generic_pm_domain *genpd) > { > struct dentry *d; > > + if (!genpd_debugfs_dir) > + return; > + > d = debugfs_lookup(genpd->name, genpd_debugfs_dir); > debugfs_remove(d); Why not just change this to be: debugfs_remove(debugfs_lookup(genpd->name, debugfs_lookup("pm_genpd", NULL))); thanks, greg k-h