From patchwork Sat Mar 10 11:19:29 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lars-Peter Clausen X-Patchwork-Id: 10273439 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 7BA0E601A0 for ; Sat, 10 Mar 2018 11:20:00 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 68C69299D2 for ; Sat, 10 Mar 2018 11:20:00 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 59E5729B5C; Sat, 10 Mar 2018 11:20:00 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 09855299D2 for ; Sat, 10 Mar 2018 11:20:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751964AbeCJLTo (ORCPT ); Sat, 10 Mar 2018 06:19:44 -0500 Received: from www381.your-server.de ([78.46.137.84]:54588 "EHLO www381.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752108AbeCJLTm (ORCPT ); Sat, 10 Mar 2018 06:19:42 -0500 Received: from [88.198.220.131] (helo=sslproxy02.your-server.de) by www381.your-server.de with esmtpsa (TLSv1.2:DHE-RSA-AES256-GCM-SHA384:256) (Exim 4.85_2) (envelope-from ) id 1eucXD-0002ED-SN; Sat, 10 Mar 2018 12:19:31 +0100 Received: from [93.104.106.31] (helo=[192.168.178.40]) by sslproxy02.your-server.de with esmtpsa (TLSv1.2:DHE-RSA-AES256-SHA:256) (Exim 4.84_2) (envelope-from ) id 1eucXD-000153-Hk; Sat, 10 Mar 2018 12:19:31 +0100 Subject: Re: Nokia N900: v4.16-rc4: oops in iio when grepping sysfs To: Pavel Machek , Greg KH , jic23@kernel.org, akinobu.mita@gmail.com, javier@osg.samsung.com, gregor.boirie@parrot.com Cc: pali.rohar@gmail.com, sre@kernel.org, kernel list , linux-arm-kernel , linux-omap@vger.kernel.org, tony@atomide.com, khilman@kernel.org, aaro.koskinen@iki.fi, ivo.g.dimitrov.75@gmail.com, patrikbachan@gmail.com, serge@hallyn.com, abcloriens@gmail.com, clayton@craftyguy.net, martijn@brixit.nl, sakari.ailus@linux.intel.com, =?UTF-8?Q?Filip_Matijevi=c4=87?= , security@kernel.org, knaack.h@gmx.de, pmeerw@pmeerw.net, linux-iio@vger.kernel.org References: <20180309221220.GA15272@amd> <20180309222821.GA16973@kroah.com> <20180309230124.GA17721@amd> From: Lars-Peter Clausen Message-ID: <1bb9aa1e-1a78-5d1c-d2d6-f2cd6b925f31@metafoo.de> Date: Sat, 10 Mar 2018 12:19:29 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <20180309230124.GA17721@amd> Content-Language: en-US X-Authenticated-Sender: lars@metafoo.de X-Virus-Scanned: Clear (ClamAV 0.99.3/24380/Sat Mar 10 10:13:47 2018) Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On 03/10/2018 12:01 AM, Pavel Machek wrote: [...] >> What file are you opening to cause this? > > Strace says: > > openat(7, "in_intensity_both_thresh_rising_en", >>> O_RDONLY|O_LARGEFILE|O_NOFOLLOW) = 3 > fstat64(3, {st_mode=S_IFREG|0644, st_size=4096, ...}) = 0 > ioctl(3, SNDCTL_TMR_TIMEBASE or TCGETS, 0xbe83b714) = -1 ENOTTY >>> (Inappropriate ioctl for device) > read(3, > Message from syslogd@localhost at Mar 9 23:54:39 ... > kernel:[ 3097.357696] Internal error: Oops: 80000007 [#2] ARM > > So that would be: > > ./devices/platform/68000000.ocp/48072000.i2c/i2c-2/2-0029/iio:device1/events/in_intensity_both_thresh_rising_en > > And indeed, manually cat-ing that file reproduces the problem. > > pavel@n900:/sys/devices/platform/68000000.ocp/48072000.i2c/i2c-2/2-0029/iio:device1$ > cat name > tsl2563 > > I can not find tsl2563 in MAINTAINERS, file is > ./drivers/iio/light/tsl2563.c . I added few people pointed by git log. The driver registers event attributes, but does not provide a handle to access those attributes. Now the question is how to best handle this case. 1) Return an error when the device is registered and abort registration 2) Skip registering the event attributes 3) Skip registering the event attributes, but print a warning 4) Register the attributes, but return an error when they are accessed I'd prefer 2 since it offers a nice method of disabling all events for a device (e.g. if not interrupt is provided). On the other hand it could cause some confusion during development, potentially causing the developer to wonder why he doesn't get any event attributes even though he setup his channel description to have event attributes. Patch for 2. Tested-by: Pavel Machek Reported-by: Pavel Machek --- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html --- a/drivers/iio/industrialio-event.c +++ b/drivers/iio/industrialio-event.c @@ -477,7 +477,8 @@ int iio_device_register_eventset(struct iio_dev struct attribute **attr; if (!(indio_dev->info->event_attrs || - iio_check_for_dynamic_events(indio_dev))) + iio_check_for_dynamic_events(indio_dev)) || + !indio_dev->info->read_event_config) return 0; indio_dev->event_interface =