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=-13.8 required=3.0 tests=BAYES_00, 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 BFB25C433ED for ; Wed, 12 May 2021 04:52:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 99EFF61421 for ; Wed, 12 May 2021 04:52:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229919AbhELExq (ORCPT ); Wed, 12 May 2021 00:53:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45640 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229495AbhELExm (ORCPT ); Wed, 12 May 2021 00:53:42 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 72876C061574 for ; Tue, 11 May 2021 21:52:33 -0700 (PDT) Received: from ptx.hi.pengutronix.de ([2001:67c:670:100:1d::c0]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lggrA-0000v7-TQ; Wed, 12 May 2021 06:52:24 +0200 Received: from ukl by ptx.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1lggr8-0000Sr-Fo; Wed, 12 May 2021 06:52:22 +0200 Date: Wed, 12 May 2021 06:52:22 +0200 From: Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= To: Zou Wei Cc: thierry.reding@gmail.com, lee.jones@linaro.org, linux-pwm@vger.kernel.org, linux-kernel@vger.kernel.org, "Rafael J. Wysocki" , Kevin Hilman , Ulf Hansson , linux-pm@vger.kernel.org Subject: Re: [PATCH -next] pwm: img: Fix PM reference leak in img_pwm_enable() Message-ID: <20210512045222.2yjm6yxikznohlmn@pengutronix.de> References: <1620791837-16138-1-git-send-email-zou_wei@huawei.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="imgrom7jqz4bbh57" Content-Disposition: inline In-Reply-To: <1620791837-16138-1-git-send-email-zou_wei@huawei.com> X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::c0 X-SA-Exim-Mail-From: ukl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --imgrom7jqz4bbh57 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hello, On Wed, May 12, 2021 at 11:57:17AM +0800, Zou Wei wrote: > pm_runtime_get_sync will increment pm usage counter even it failed. > Forgetting to putting operation will result in reference leak here. > Fix it by replacing it with pm_runtime_resume_and_get to keep usage > counter balanced. >=20 > Reported-by: Hulk Robot > Signed-off-by: Zou Wei > --- > drivers/pwm/pwm-img.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) >=20 > diff --git a/drivers/pwm/pwm-img.c b/drivers/pwm/pwm-img.c > index cc37054..11b16ec 100644 > --- a/drivers/pwm/pwm-img.c > +++ b/drivers/pwm/pwm-img.c > @@ -156,7 +156,7 @@ static int img_pwm_enable(struct pwm_chip *chip, stru= ct pwm_device *pwm) > struct img_pwm_chip *pwm_chip =3D to_img_pwm_chip(chip); > int ret; > =20 > - ret =3D pm_runtime_get_sync(chip->dev); > + ret =3D pm_runtime_resume_and_get(chip->dev); > if (ret < 0) > return ret; This patch looks right with my limited understanding of pm_runtime. A similar issue in this driver was fixed in commit ca162ce98110 ("pwm: img: Call pm_runtime_put() in pm_runtime_get_sync() fa= iled case") where (even though the commit log talks about pm_runtime_put()) a call to pm_runtime_put_autosuspend() was added in the error path. I added the PM guys to Cc, maybe they can advise about the right thing to do here. Does it make sense to use the same idiom in both img_pwm_enable() and img_pwm_config()? Best regards Uwe --=20 Pengutronix e.K. | Uwe Kleine-K=F6nig | Industrial Linux Solutions | https://www.pengutronix.de/ | --imgrom7jqz4bbh57 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEfnIqFpAYrP8+dKQLwfwUeK3K7AkFAmCbXwEACgkQwfwUeK3K 7AlCPwgAkM9Sh0ifE0Y5Eu35Z8CC/bngNLYdoDyE+ULVT9SN/bbSKOP8eYYNEy8D yo+SqECIwLflbocvxUkWb1s3cdFgn+zeOJ3uEtXT7NwQ6Fv0ke/nGh3iNjDAKkUI pPhhizrOwzC3ODTpUIN6CN+MH1wlK9ArPipN/RyEeJbUVv7R5AaI7i5u7N8N3iFh HBGw+9Ir0zIgxb2mvxobd/If4jeXHvQaubKrNcf5mRuE+0cWib5VpGz5jIsYEnyo vozif4bqSYUHEo83z6aNz1kNFjKR/iqI+wkw16466GzpJzFHZfCDorWALMvlVBjT uSjVEW901G1gZOhRU4LjDypcdYVLQw== =RcVx -----END PGP SIGNATURE----- --imgrom7jqz4bbh57--