From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751427Ab2LSHhe (ORCPT ); Wed, 19 Dec 2012 02:37:34 -0500 Received: from h1446028.stratoserver.net ([85.214.92.142]:46189 "EHLO mail.ahsoftware.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751544Ab2LSHh1 (ORCPT ); Wed, 19 Dec 2012 02:37:27 -0500 Message-ID: <50D16EA3.8040803@ahsoftware.de> Date: Wed, 19 Dec 2012 08:37:07 +0100 From: Alexander Holler User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/17.0 Thunderbird/17.0 MIME-Version: 1.0 To: Andrew Morton CC: Vincent Palatin , rtc-linux@googlegroups.com, Alessandro Zummo , linux-kernel@vger.kernel.org Subject: Re: [rtc-linux] [PATCH] rtc: recycle id when unloading a rtc driver References: <1343951605-25722-1-git-send-email-vpalatin@chromium.org> <20121218164659.a3d3655a.akpm@linux-foundation.org> In-Reply-To: <20121218164659.a3d3655a.akpm@linux-foundation.org> Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am 19.12.2012 01:46, schrieb Andrew Morton: > On Thu, 2 Aug 2012 16:53:25 -0700 > Vincent Palatin wrote: > >> When calling rtc_device_unregister, we are not freeing the id used by the >> driver. >> So when doing a unload/load cycle for a RTC driver (e.g. rmmod rtc_cmos >> && modprobe rtc_cmos), its id is incremented by one. As a consequence, >> we no longer have neither an rtc0 driver nor a /proc/driver/rtc (as it >> only exists for the first driver). >> >> Signed-off-by: Vincent Palatin >> --- >> drivers/rtc/class.c | 1 + >> 1 files changed, 1 insertions(+), 0 deletions(-) >> >> diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c >> index dc4c274..37b1d82 100644 >> --- a/drivers/rtc/class.c >> +++ b/drivers/rtc/class.c >> @@ -238,6 +238,7 @@ void rtc_device_unregister(struct rtc_device *rtc) >> rtc_proc_del_device(rtc); >> device_unregister(&rtc->dev); >> rtc->ops = NULL; >> + ida_simple_remove(&rtc_ida, rtc->id); >> mutex_unlock(&rtc->ops_lock); >> put_device(&rtc->dev); >> } > > Now I think about it, this shouldn't have been needed? > > That put_device() should call rtc_device_release(), which does the > ida_simple_remove(). Isn't that working? It is, see the mini-thread, patch and my comment here: https://lkml.org/lkml/2012/12/6/152 Maybe it would be better to move the ida_simple_remove from the rtc_device_release to rt_device_unregister as I've hinted in the above comment. That would make it easier to spot the ida_simple_remove(). Regards, Alexander