From patchwork Wed May 25 10:56:51 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wolfram Sang X-Patchwork-Id: 97326 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from mail-wy0-f184.google.com (mail-wy0-f184.google.com [74.125.82.184]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id 2CDE7B6F92 for ; Wed, 25 May 2011 20:57:18 +1000 (EST) Received: by wyb35 with SMTP id 35sf14151371wyb.11 for ; Wed, 25 May 2011 03:57:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlegroups.com; s=beta; h=domainkey-signature:mime-version:x-beenthere:received-spf:from:to :cc:subject:date:message-id:x-mailer:in-reply-to:references :x-sa-exim-connect-ip:x-sa-exim-mail-from:x-sa-exim-scanned :x-ptx-original-recipient:x-original-sender :x-original-authentication-results:reply-to:precedence:mailing-list :list-id:x-google-group-id:list-post:list-help:list-archive:sender :list-subscribe:list-unsubscribe:content-type; bh=QfjyaXSGbPSvP0bI5qUs8ttN1WvPxi7hsM9L5rP51Nw=; b=cCpaGLtpD54RT6ct4HDwwEv4b7HTro+i3HaLCb/QT8zkV2JtFmS2Q6iWTnEcV4B0ve Vw4GiQVK1PTYzv2GGD3YiX3dinOv2ng2xImfVT8skkf/XQlcrpaUvO/JGVFNFbdEFn8X 5YqnnxLZ5MjtEwo3gwJyJLspfrErTwfpWqYq8= DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlegroups.com; s=beta; h=mime-version:x-beenthere:received-spf:from:to:cc:subject:date :message-id:x-mailer:in-reply-to:references:x-sa-exim-connect-ip :x-sa-exim-mail-from:x-sa-exim-scanned:x-ptx-original-recipient :x-original-sender:x-original-authentication-results:reply-to :precedence:mailing-list:list-id:x-google-group-id:list-post :list-help:list-archive:sender:list-subscribe:list-unsubscribe :content-type; b=iDve5G1pO/7wjbWBErTn3/Z8QPA3Mo+NWGReM2cTIYyAS7/jc20sZBN+R8BrjPXdNN QiWPdB3ci1BmrkZorc/rZfKpjHaawXGE0MhOxzztYqyDpgVj1MopffuO+MSVgtY8CgQv U1Fx6e9eKc9JV8caJO2oDJfYiSwbIS6qlCH4o= Received: by 10.217.7.4 with SMTP id z4mr1708291wes.4.1306321033959; Wed, 25 May 2011 03:57:13 -0700 (PDT) MIME-Version: 1.0 X-BeenThere: rtc-linux@googlegroups.com Received: by 10.217.4.3 with SMTP id t3ls161728wes.1.gmail; Wed, 25 May 2011 03:57:13 -0700 (PDT) Received: by 10.216.121.76 with SMTP id q54mr347128weh.14.1306321033443; Wed, 25 May 2011 03:57:13 -0700 (PDT) Received: by 10.216.121.76 with SMTP id q54mr347127weh.14.1306321033414; Wed, 25 May 2011 03:57:13 -0700 (PDT) Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [92.198.50.35]) by gmr-mx.google.com with ESMTPS id 38si542293wby.3.2011.05.25.03.57.12 (version=TLSv1/SSLv3 cipher=OTHER); Wed, 25 May 2011 03:57:12 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of w.sang@pengutronix.de designates 92.198.50.35 as permitted sender) client-ip=92.198.50.35; Received: from katana.hi.pengutronix.de ([2001:6f8:1178:2:221:70ff:fe71:1890] helo=pengutronix.de) by metis.ext.pengutronix.de with esmtp (Exim 4.72) (envelope-from ) id 1QPBm3-00085T-LC; Wed, 25 May 2011 12:57:11 +0200 From: Wolfram Sang To: rtc-linux@googlegroups.com Cc: linux-arm-kernel@lists.infradead.org, John Stultz , Andrew Morton , Wolfram Sang Subject: [rtc-linux] [PATCH V2 3/5] rtc: stmp3xxx: Initialize drvdata before registering device Date: Wed, 25 May 2011 12:56:51 +0200 Message-Id: <1306321013-28364-4-git-send-email-w.sang@pengutronix.de> X-Mailer: git-send-email 1.7.2.5 In-Reply-To: <1306321013-28364-1-git-send-email-w.sang@pengutronix.de> References: <1306321013-28364-1-git-send-email-w.sang@pengutronix.de> X-SA-Exim-Connect-IP: 2001:6f8:1178:2:221:70ff:fe71:1890 X-SA-Exim-Mail-From: w.sang@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: rtc-linux@googlegroups.com X-Original-Sender: w.sang@pengutronix.de X-Original-Authentication-Results: gmr-mx.google.com; spf=pass (google.com: best guess record for domain of w.sang@pengutronix.de designates 92.198.50.35 as permitted sender) smtp.mail=w.sang@pengutronix.de Reply-To: rtc-linux@googlegroups.com Precedence: list Mailing-list: list rtc-linux@googlegroups.com; contact rtc-linux+owners@googlegroups.com List-ID: X-Google-Group-Id: 712029733259 List-Post: , List-Help: , List-Archive: Sender: rtc-linux@googlegroups.com List-Subscribe: , List-Unsubscribe: , Commit f44f7f96a20 ("RTC: Initialize kernel state from RTC") uncovered an issue in a number of RTC drivers, where the drivers call rtc_device_register before initializing the device or platform drvdata. This frequently results in null pointer dereferences when the rtc_device_register immediately makes use of the rtc device, calling rtc_read_alarm. The solution is to ensure the drvdata is initialized prior to registering the rtc device. Signed-off-by: Wolfram Sang Tested-by: Shawn Guo --- Thanks to John for the commit-msg ;) drivers/rtc/rtc-stmp3xxx.c | 7 +++++-- 1 files changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/rtc/rtc-stmp3xxx.c b/drivers/rtc/rtc-stmp3xxx.c index 44e2202..fae563a 100644 --- a/drivers/rtc/rtc-stmp3xxx.c +++ b/drivers/rtc/rtc-stmp3xxx.c @@ -172,6 +172,7 @@ static int stmp3xxx_rtc_remove(struct platform_device *pdev) free_irq(rtc_data->irq_alarm, &pdev->dev); free_irq(rtc_data->irq_1msec, &pdev->dev); rtc_device_unregister(rtc_data->rtc); + platform_set_drvdata(pdev, NULL); iounmap(rtc_data->io); kfree(rtc_data); @@ -212,11 +213,14 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev) goto out_remap; } + platform_set_drvdata(pdev, rtc_data); + mxs_reset_block(rtc_data->io); __mxs_clrl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN | STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE, rtc_data->io + STMP3XXX_RTC_PERSISTENT0); + rtc_data->rtc = rtc_device_register(pdev->name, &pdev->dev, &stmp3xxx_rtc_ops, THIS_MODULE); if (IS_ERR(rtc_data->rtc)) { @@ -240,8 +244,6 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev) goto out_irq1; } - platform_set_drvdata(pdev, rtc_data); - return 0; out_irq1: @@ -251,6 +253,7 @@ out_irq_alarm: rtc_data->io + STMP3XXX_RTC_CTRL); rtc_device_unregister(rtc_data->rtc); out_remap: + platform_set_drvdata(pdev, NULL); iounmap(rtc_data->io); out_free: kfree(rtc_data);