Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755389AbYKCLxT (ORCPT ); Mon, 3 Nov 2008 06:53:19 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753668AbYKCLxH (ORCPT ); Mon, 3 Nov 2008 06:53:07 -0500 Received: from ik-out-1112.google.com ([66.249.90.176]:16265 "EHLO ik-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753663AbYKCLxG (ORCPT ); Mon, 3 Nov 2008 06:53:06 -0500 Message-ID: Date: Mon, 3 Nov 2008 12:53:03 +0100 From: "Kay Sievers" To: "Peter Zijlstra" Subject: Re: [2.6.26] kobject_add_internal failed for 2:0 with -EEXIST / unable to handle kernel NULL pointer dereference in sysfs_create_link Cc: "Folkert van Heusden" , linux-kernel@vger.kernel.org In-Reply-To: <1225445335.7803.1214.camel@twins> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20081028151157.GI11214@vanheusden.com> <20081029132704.GS11214@vanheusden.com> <20081029152550.GT11214@vanheusden.com> <20081030105513.GY11214@vanheusden.com> <1225445335.7803.1214.camel@twins> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1544 Lines: 41 On Fri, Oct 31, 2008 at 10:28, Peter Zijlstra wrote: > On Fri, 2008-10-31 at 00:23 +0100, Kay Sievers wrote: > >> Peter, it looks like bdi does not work for devices which share a single queue. >> If I add: >> --- a/mm/backing-dev.c >> +++ b/mm/backing-dev.c >> @@ -184,6 +184,8 @@ int bdi_register(struct backing_dev_info *bdi, >> struct device *parent, >> goto exit; >> } >> >> + printk("XXXXXXX old bdidev is %p\n", bdi->dev); >> + printk("XXXXXXX new bdidev is %p\n", dev); >> bdi->dev = dev; >> bdi_debug_register(bdi, dev_name(dev)); >> >> I get: >> $ modprobe floppy >> Floppy drive(s): fd0 is 1.44M, fd1 is 1.44M >> FDC 0 is a S82078B >> XXXXXXX old bdidev is 0000000000000000 >> XXXXXXX new bdidev is ffff88001f20cd10 >> XXXXXXX old bdidev is ffff88001f20cd10 >> XXXXXXX new bdidev is ffff88001f20de30 >> >> which very much looks like bdi will not remove any earlier registered >> device, only the last one, right? > > Sharing a bdi is odd to begin with, let me poke at this a little. Yeah, it's odd, but I'm not sure if you want to touch floppy.c. :) Any objection to this patch, until you possible fix it differently? http://marc.info/?l=linux-kernel&m=122541569310798&w=4 Kay -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/