From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: Re: sysfs change of input/event devices in 2.6.23rc breaks udev Date: Sat, 15 Sep 2007 01:05:19 -0700 Message-ID: <20070915010519.34bcb9ae.akpm@linux-foundation.org> References: <46E2D712.1010402@gmail.com> <3ae72650709091603o57c976d1q8a1b5492ef041186@mail.gmail.com> <200709100128.48595.dtor@insightbb.com> <20070910054448.GA3515@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: owner-linux-input@atrey.karlin.mff.cuni.cz List-Help: List-Owner: List-Post: List-Unsubscribe: To: Dmitry Torokhov Cc: Greg KH , Kay Sievers , Anssi Hannula , linux-input@atrey.karlin.mff.cuni.cz, linux-kernel@vger.kernel.org List-Id: linux-input@vger.kernel.org On Mon, 10 Sep 2007 09:24:04 -0400 "Dmitry Torokhov" wrote: > On 9/10/07, Greg KH wrote: > > On Mon, Sep 10, 2007 at 01:28:47AM -0400, Dmitry Torokhov wrote: > > > On Sunday 09 September 2007 19:03, Kay Sievers wrote: > > > > On 9/8/07, Anssi Hannula wrote: > > > > > > > > > > However, the change that broke id_path of udev is that > > > > > /sys/class/input/event5/device is now a symlink to the inputX directory > > > > > instead of being the same as the device symlink in inputX directory, > > > > > i.e. to ../../../devices/platform/pcspkr in this case. > > > > > > > > > > Udev id_path uses that directory to construct the ID_PATH variable. > > > > > Should the sysfs structure be reverted or should udev be adapted to > > > > > handle traversing /device symlink twice? I think the former, as there > > > > > should be considerably more time to adapt udev for coming changes in sysfs. > > > > > > > > Udev's path_id script is too dumb to follow the "device" link of > > > > stacked class devices in the CONFIG_SYSFS_DEPRECATED=y layout. Does > > > > this change fix it for you? > > > > http://git.kernel.org/?p=linux/hotplug/udev.git;a=commitdiff_plain;h=b1ac36ff5e3756cefc79967a26280056da31bf6f > > > > > > > > > > Hmm, fixing udev is good but users will not get the change in time. I think we > > > need to adjust SYSFS_DEPRECATED code to produce old results. Something like the > > > patch below. I wonder what Greg would think... > > > > Hm, I don't understand. Didn't the original conversion of the input > > layer by Kay not have this kind of problem? What did your changes do > > differently to cause this driver core change to be needed? > > > > If I understand it correctly Kay's convesion had the same issue. With > class devices "device" link points to class_dev->device instead of > class_dev->parent. If you want to keep compatibility with old sysfs > layout when moving from class devices to regular devices then you need > to "skip" couple of parents till you get to "real" device. This only > matters for input because this was the only subsystem with class > devices stacked. > Did this userspace-visible post-2.6.22 regression get fixed?