From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752119Ab2CKL4f (ORCPT ); Sun, 11 Mar 2012 07:56:35 -0400 Received: from mail-iy0-f174.google.com ([209.85.210.174]:38986 "EHLO mail-iy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751591Ab2CKL4d convert rfc822-to-8bit (ORCPT ); Sun, 11 Mar 2012 07:56:33 -0400 MIME-Version: 1.0 In-Reply-To: <20120309233659.GA21256@kroah.com> References: <201203032122.36745.chunkeey@googlemail.com> <4F551E46.7000100@linux.vnet.ibm.com> <201203092330.24438.chunkeey@googlemail.com> <20120309233659.GA21256@kroah.com> From: Kay Sievers Date: Sun, 11 Mar 2012 12:56:13 +0100 Message-ID: Subject: Re: [PATCH] firmware loader: don't cancel _nowait requests when helper is not yet available To: Greg KH Cc: Christian Lamparter , linux-kernel@vger.kernel.org, "Srivatsa S. Bhat" , alan@lxorguk.ukuu.org.uk, "Rafael J. Wysocki" , Linus Torvalds , Linux PM mailing list Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Mar 10, 2012 at 00:36, Greg KH wrote: > On Fri, Mar 09, 2012 at 11:30:24PM +0100, Christian Lamparter wrote: >> This patch fixes a regression which was introduced by: >> "PM: Print a warning if firmware is requested when tasks are frozen" >> >> request_firmware_nowait does not stall in any system resume paths. >> Therefore, I think it is perfectly save to use request_firmware_nowait >> from at least the ->complete() callback. > > Is there code somewhere in the kernel that wants to do this?  Has commit > a144c6a broken it somehow that this fix would resolve it? > >> >> Signed-off-by: Christian Lamparter >> --- >>  drivers/base/firmware_class.c |    2 +- >>  1 files changed, 1 insertions(+), 1 deletions(-) >> >> diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c >> index 6c9387d..017e020 100644 >> --- a/drivers/base/firmware_class.c >> +++ b/drivers/base/firmware_class.c >> @@ -535,7 +535,7 @@ static int _request_firmware(const struct firmware **firmware_p, >> >>       read_lock_usermodehelper(); >> >> -     if (WARN_ON(usermodehelper_is_disabled())) { >> +     if (WARN_ON(usermodehelper_is_disabled() && !(nowait && uevent))) { > > What does uevent have to do with things here? I don't think that the firmware loader should care about the usermodehelper at all, and that stuff fiddling should just be removed from the firmware class. Forking /sbin/hotplug is disabled by default, it is a broken concept, and it cannot work reliably on today's systems. Firmware is not loaded by /sbin/hotplug since many years, but by udev or whatever service handles uevents, like ueventd on android. Kay