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 BD755C49EA7 for ; Fri, 25 Jun 2021 17:33:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9DE9361960 for ; Fri, 25 Jun 2021 17:33:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229586AbhFYRfs (ORCPT ); Fri, 25 Jun 2021 13:35:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42612 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229531AbhFYRfr (ORCPT ); Fri, 25 Jun 2021 13:35:47 -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 A5251C061574 for ; Fri, 25 Jun 2021 10:33:26 -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 1lwphf-0004IA-M0; Fri, 25 Jun 2021 19:33:19 +0200 Received: from ukl by ptx.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1lwphd-0005va-3n; Fri, 25 Jun 2021 19:33:17 +0200 Date: Fri, 25 Jun 2021 19:33:16 +0200 From: Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= To: "Rafael J. Wysocki" , Kevin Hilman , Ulf Hansson , linux-pm@vger.kernel.org Cc: Zou Wei , thierry.reding@gmail.com, lee.jones@linaro.org, linux-pwm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH -next] pwm: img: Fix PM reference leak in img_pwm_enable() Message-ID: <20210625173316.pfsk7rvlplv4bzef@pengutronix.de> References: <1620791837-16138-1-git-send-email-zou_wei@huawei.com> <20210512045222.2yjm6yxikznohlmn@pengutronix.de> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="nw3jy26dwfiaqji6" Content-Disposition: inline In-Reply-To: <20210512045222.2yjm6yxikznohlmn@pengutronix.de> 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-pwm@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pwm@vger.kernel.org --nw3jy26dwfiaqji6 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hello Rafael, Kevin and Ulf, On Wed, May 12, 2021 at 06:52:22AM +0200, Uwe Kleine-K=F6nig wrote: > Hello, >=20 > 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, st= ruct 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; >=20 > This patch looks right with my limited understanding of pm_runtime. A > similar issue in this driver was fixed in commit >=20 > ca162ce98110 ("pwm: img: Call pm_runtime_put() in pm_runtime_get_sync() = failed case") >=20 > where (even though the commit log talks about pm_runtime_put()) a call > to pm_runtime_put_autosuspend() was added in the error path. >=20 > 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()? Can you give some feedback here? Best regards Uwe --=20 Pengutronix e.K. | Uwe Kleine-K=F6nig | Industrial Linux Solutions | https://www.pengutronix.de/ | --nw3jy26dwfiaqji6 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEfnIqFpAYrP8+dKQLwfwUeK3K7AkFAmDWE1kACgkQwfwUeK3K 7AlMHAf/Seh27QiCuoDAcLlJ+osf/17c6RGJV3u5TfaG84noBRtpFr5rz8bKOQMT UJ/ElYO8+dIcwhxvnp6ZUuHl3x7faYThWxvQxGn4qSUN5qw2N6gpjoQ3r6HEaPU0 vk/DdsxgXGv1g3LT3jkPM6t5lkGS9b6wQZhUxzO9ybsJNzYnK+1h8wqWr9Wz723P tVfFGiEiGvHpCY7B3f93AKiAQmJKIHsbg9w/p5GVeNOs/ipgqAGzvRra9uw941mY ItQSWvCloxcuCDpYFJLlQPzH41O3YgruK3QP4YD+raLoberxAmzQIGmTAjqWC4UG YbSq8uAkzioI+BT3Rd3UYjXdWBd3SA== =Jgez -----END PGP SIGNATURE----- --nw3jy26dwfiaqji6--