From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lothar =?UTF-8?B?V2HDn21hbm4=?= Subject: Re: [PATCH] clk: Correct handling of NULL clk in __clk_{get, put} Date: Tue, 7 Jan 2014 14:00:19 +0100 Message-ID: <20140107140019.7220eed6@ipc1.ka-ro> References: <1389096223-23934-1-git-send-email-s.nawrocki@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail.karo-electronics.de ([81.173.242.67]:55871 "EHLO mail.karo-electronics.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751741AbaAGNAd convert rfc822-to-8bit (ORCPT ); Tue, 7 Jan 2014 08:00:33 -0500 In-Reply-To: <1389096223-23934-1-git-send-email-s.nawrocki@samsung.com> Sender: linux-samsung-soc-owner@vger.kernel.org List-Id: linux-samsung-soc@vger.kernel.org To: Sylwester Nawrocki Cc: sachin.kamat@linaro.org, linux-samsung-soc@vger.kernel.org, mturquette@linaro.org, tomasz.figa@gmail.com, linux-arm-kernel@lists.infradead.org Hi, Sylwester Nawrocki wrote: > Ensure clk->kref is dereferenced only when clk is not NULL. >=20 > Signed-off-by: Sylwester Nawrocki > --- > Hi Sachin, >=20 > please try if this patch fixes the exyno5420 boot crash. >=20 > Thanks, > Sylwester >=20 > drivers/clk/clk.c | 13 +++++++------ > 1 file changed, 7 insertions(+), 6 deletions(-) >=20 > diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c > index e3e0327..a1fe86f 100644 > --- a/drivers/clk/clk.c > +++ b/drivers/clk/clk.c > @@ -2179,24 +2179,25 @@ EXPORT_SYMBOL_GPL(devm_clk_unregister); > */ > int __clk_get(struct clk *clk) > { > - if (clk && !try_module_get(clk->owner)) > - return 0; > + if (clk) { > + if (!try_module_get(clk->owner)) > + return 0; >=20 This change is unnecessary! The part after the && is only evaluated when clk is not NULL. Lothar Wa=C3=9Fmann --=20 ___________________________________________________________ Ka-Ro electronics GmbH | Pascalstra=C3=9Fe 22 | D - 52076 Aachen Phone: +49 2408 1402-0 | Fax: +49 2408 1402-10 Gesch=C3=A4ftsf=C3=BChrer: Matthias Kaussen Handelsregistereintrag: Amtsgericht Aachen, HRB 4996 www.karo-electronics.de | info@karo-electronics.de ___________________________________________________________ From mboxrd@z Thu Jan 1 00:00:00 1970 From: LW@KARO-electronics.de (Lothar =?UTF-8?B?V2HDn21hbm4=?=) Date: Tue, 7 Jan 2014 14:00:19 +0100 Subject: [PATCH] clk: Correct handling of NULL clk in __clk_{get, put} In-Reply-To: <1389096223-23934-1-git-send-email-s.nawrocki@samsung.com> References: <1389096223-23934-1-git-send-email-s.nawrocki@samsung.com> Message-ID: <20140107140019.7220eed6@ipc1.ka-ro> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi, Sylwester Nawrocki wrote: > Ensure clk->kref is dereferenced only when clk is not NULL. > > Signed-off-by: Sylwester Nawrocki > --- > Hi Sachin, > > please try if this patch fixes the exyno5420 boot crash. > > Thanks, > Sylwester > > drivers/clk/clk.c | 13 +++++++------ > 1 file changed, 7 insertions(+), 6 deletions(-) > > diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c > index e3e0327..a1fe86f 100644 > --- a/drivers/clk/clk.c > +++ b/drivers/clk/clk.c > @@ -2179,24 +2179,25 @@ EXPORT_SYMBOL_GPL(devm_clk_unregister); > */ > int __clk_get(struct clk *clk) > { > - if (clk && !try_module_get(clk->owner)) > - return 0; > + if (clk) { > + if (!try_module_get(clk->owner)) > + return 0; > This change is unnecessary! The part after the && is only evaluated when clk is not NULL. Lothar Wa?mann -- ___________________________________________________________ Ka-Ro electronics GmbH | Pascalstra?e 22 | D - 52076 Aachen Phone: +49 2408 1402-0 | Fax: +49 2408 1402-10 Gesch?ftsf?hrer: Matthias Kaussen Handelsregistereintrag: Amtsgericht Aachen, HRB 4996 www.karo-electronics.de | info at karo-electronics.de ___________________________________________________________