From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753033AbaH2HT5 (ORCPT ); Fri, 29 Aug 2014 03:19:57 -0400 Received: from smtp89.ord1c.emailsrvr.com ([108.166.43.89]:51025 "EHLO smtp89.ord1c.emailsrvr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751955AbaH2HTz (ORCPT ); Fri, 29 Aug 2014 03:19:55 -0400 X-Sender-Id: pramod.gurav@smartplayin.com Message-ID: <5400297F.9000702@smartplayin.com> Date: Fri, 29 Aug 2014 12:49:27 +0530 From: Pramod Gurav User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.0 MIME-Version: 1.0 To: Bjorn Andersson CC: Bjorn Andersson , "linux-kernel@vger.kernel.org" , linux-arm-msm , "Ivan T. Ivanov" , Linus Walleij Subject: Re: [PATCH] pinctrl: qcom: Release pin ranges when gpiochip_irqchip_add fails References: <1409137049-15848-1-git-send-email-pramod.gurav@smartplayin.com> <53FED69B.3020406@smartplayin.com> <20140829034900.GF12494@sonymobile.com> In-Reply-To: <20140829034900.GF12494@sonymobile.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 29-08-2014 09:19 AM, Bjorn Andersson wrote: > On Thu 28 Aug 00:13 PDT 2014, Pramod Gurav wrote: > >> On Thursday 28 August 2014 02:54 AM, Bjorn Andersson wrote: >>> On Wed, Aug 27, 2014 at 3:57 AM, Pramod Gurav >>> wrote: >>>> This patches adds a call to gpiochip_remove_pin_ranges when >>>> gpiochip_irqchip_add fails to release memory allocated for pin_ranges. >>>> >>>> diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c >>>> @@ -845,6 +845,7 @@ static int msm_gpio_init(struct msm_pinctrl *pctrl) >>>> IRQ_TYPE_NONE); >>>> if (ret) { >>>> dev_err(pctrl->dev, "Failed to add irqchip to gpiochip\n"); >>>> + gpiochip_remove_pin_ranges(chip); >>>> return -ENOSYS; >>>> } >>> >>> Good catch, I guess this was lost in the introduction of gpiochip_irqchip... >>> >>> >>> Rather than just releasing the pin_ranges of the gpio_chip you should >>> probably add a gpiochip_remove() both here and in the case of >>> gpiochip_add_pin_range() failing. >> >> Thanks for review. But if I see implementation of gpiochip_remove() it does: >> gpiochip_irqchip_remove(chip); >> gpiochip_remove_pin_ranges(chip); >> of_gpiochip_remove(chip); >> >> In above failure case only gpiochip_add() and gpiochip_add_pin_range() >> have been successful hence I thought that would cause any problem to add >> gpiochip_remove(). If that is not a problem I think we can call >> gpiochip_remove() in fail case of gpiochip_add_pin_range() as well. >> Do I make sense? >> > > As soon as gpiochip_add() have returned successfully we will have a live > gpio_chip, upon returning unsuccessfully from probe devres will free the pctrl > node and the gpio core will continue to operate on freed memory. > > Therefor we need to call gpio_remove() in the ccase of both > gpiochip_add_pin_range() and gpiochip_irqchip_add() failing. > > The gpio_remove() does as you say remove those additional items, but handles > the case where they are not yet "allocated". > > I hope this answers your conserns. That really does. Thanks for your time. Will resend the patch with handling failure cases of both gpiochip_add_pin_range() and gpiochip_irqchip_add(). > > Regards, > Bjorn > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ >