From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752732Ab1AYFHd (ORCPT ); Tue, 25 Jan 2011 00:07:33 -0500 Received: from ironport2-out.teksavvy.com ([206.248.154.181]:30732 "EHLO ironport2-out.pppoe.ca" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752198Ab1AYFHb (ORCPT ); Tue, 25 Jan 2011 00:07:31 -0500 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: ApIBAH/pPU1Ld/sX/2dsb2JhbAAMhAfMYpBigSSDOHQEhRc X-IronPort-AV: E=Sophos;i="4.60,372,1291611600"; d="scan'208";a="89131682" Message-ID: <4D3E5A91.30207@teksavvy.com> Date: Tue, 25 Jan 2011 00:07:29 -0500 From: Mark Lord User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-GB; rv:1.9.2.13) Gecko/20101207 Thunderbird/3.1.7 MIME-Version: 1.0 To: Dmitry Torokhov CC: Linux Kernel , linux-input@vger.kernel.org Subject: Re: 2.6.36/2.6.37: broken compatibility with userspace input-utils ? References: <4D3C5F73.2050408@teksavvy.com> <20110124175456.GA17855@core.coreip.homeip.net> <4D3E1A08.5060303@teksavvy.com> <20110125005555.GA18338@core.coreip.homeip.net> <4D3E4DD1.60705@teksavvy.com> <20110125042016.GA7850@core.coreip.homeip.net> <4D3E5372.9010305@teksavvy.com> <20110125045559.GB7850@core.coreip.homeip.net> <4D3E59CA.6070107@teksavvy.com> In-Reply-To: <4D3E59CA.6070107@teksavvy.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11-01-25 12:04 AM, Mark Lord wrote: > On 11-01-24 11:55 PM, Dmitry Torokhov wrote: >> On Mon, Jan 24, 2011 at 11:37:06PM -0500, Mark Lord wrote: > .. >>> This results in (map->size==10) for 2.6.36+ (wrong), >>> and a much larger map->size for 2.6.35 and earlier. >>> >>> So perhaps EVIOCGKEYCODE has changed? >>> >> >> So the utility expects that all devices have flat scancode space and >> driver might have changed so it does not recognize scancode 10 as valid >> scancode anymore. >> >> The options are: >> >> 1. Convert to EVIOCGKEYCODE2 >> 2. Ignore errors from EVIOCGKEYCODE and go through all 65536 iterations. > > or 3. Revert/fix the in-kernel regression. > > The EVIOCGKEYCODE ioctl is supposed to return KEY_RESERVED for unmapped > (but value) keycodes, and only return -EINVAL when the keycode itself > is out of range. > > That's how it worked in all kernels prior to 2.6.36, > and now it is broken. It now returns -EINVAL for any unmapped keycode, > even though keycodes higher than that still have mappings. > > This is a bug, a regression, and breaks userspace. > I haven't identified *where* in the kernel the breakage happened, > though.. that code confuses me. :) Note that this device DOES have "flat scancode space", and the kernel is now incorrectly signalling an error (-EINVAL) in response to a perfectly valid query of a VALID (and mappable) keycode on the remote control The code really is a valid button, it just doesn't have a default mapping set by the kernel (I can set a mapping for that code from userspace and it works). This is a BUG. Returning -EINVAL here is entirely wrong. Cheers