From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vincent Pelletier Subject: Re: [PATCH] kernel/resource.c: fix muxed resource handling in __request_region() Date: Tue, 23 Feb 2016 09:00:24 +0100 Message-ID: <20160223090024.2963da69@x2> References: <20150909220140.GD9892@kw.sim.vm.gnt> <1441836918-24159-1-git-send-email-simon.guinot@sequanux.org> <20160219221056.23487da2@x2> <56C7A459.1090801@virtuousgeek.org> <15300c0ce08.2710.f266623ac48c822f02e65082a71b2734@virtuousgeek.org> <1456148952.24303.273.camel@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: Received: from mail-wm0-f51.google.com ([74.125.82.51]:35559 "EHLO mail-wm0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932326AbcBWH5z (ORCPT ); Tue, 23 Feb 2016 02:57:55 -0500 In-Reply-To: <1456148952.24303.273.camel@linux.intel.com> Sender: linux-gpio-owner@vger.kernel.org List-Id: linux-gpio@vger.kernel.org To: Alan Cox Cc: Jesse Barnes , Linus Torvalds , Simon Guinot , Giel van Schijndel , linux-gpio@vger.kernel.org, Linux Kernel Mailing List , Vincent Donnefort , Yoann Sculo On Mon, 22 Feb 2016 13:49:12 +0000, Alan Cox wrote: > It's not used much, especially nowdays. The use case is basically multi > I/O chips on the ISA/LPC bus with magic shared config register ports. This is precisely a super I/O driver (gpio-f7188x) which, when used with concurrent accesses on an SMP machine triggered the issue which prompted this patch. In case information on the original issue is desired: My original report (ignore attached patch, it was rejected as it breaks other chips supported by this driver): http://permalink.gmane.org/gmane.linux.kernel.gpio/10204 My test procedure (second half of the mail), which I used to validate the patch against 4.1: http://permalink.gmane.org/gmane.linux.kernel.gpio/10216 Simon Guinot & Vincent Donnefort debugging results: http://permalink.gmane.org/gmane.linux.kernel.gpio/10521 Regards, -- Vincent Pelletier