From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: Re: [PATCH 3.7+stable] pm: fix wrong error-checking condition Date: Fri, 23 Nov 2012 21:36:55 +0100 Message-ID: <2410876.0MhetLSqTZ@vostro.rjw.lan> References: Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7Bit Return-path: Received: from ogre.sisk.pl ([193.178.161.156]:35348 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756207Ab2KWUcX (ORCPT ); Fri, 23 Nov 2012 15:32:23 -0500 In-Reply-To: Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Guennadi Liakhovetski Cc: linux-pm@vger.kernel.org On Friday, November 23, 2012 04:02:56 PM Guennadi Liakhovetski wrote: > dev_pm_qos_add_request() can return 0, 1, or a negative error code, > therefore the correct error test is "if (error < 0)." Checking just for > non-zero return code leads to erroneous setting of the req->dev pointer > to NULL, which then leads to a repeated call to > dev_pm_qos_add_ancestor_request() in st1232_ts_irq_handler(). This in turn > leads to an Oops, when the I2C host adapter is unloaded and reloaded again > because of the inconsistent state of its QoS request list. > > Signed-off-by: Guennadi Liakhovetski > --- > > Hi Rafael, please push to 3.7 and to stable. I will, thanks for the fix! Rafael > drivers/base/power/qos.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/drivers/base/power/qos.c b/drivers/base/power/qos.c > index 74a67e0..fbbd4ed 100644 > --- a/drivers/base/power/qos.c > +++ b/drivers/base/power/qos.c > @@ -451,7 +451,7 @@ int dev_pm_qos_add_ancestor_request(struct device *dev, > if (ancestor) > error = dev_pm_qos_add_request(ancestor, req, value); > > - if (error) > + if (error < 0) > req->dev = NULL; > > return error; > -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center.