From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dan Williams Subject: Re: [resend PATCH] scsi_remove_target: fix softlockup regression on hot remove Date: Wed, 29 Aug 2012 07:59:21 -0700 Message-ID: <1346252361.27020.8.camel@localhost.localdomain> References: <20120829051119.26395.15980.stgit@localhost.localdomain> <503DBBA0.5060108@acm.org> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:34464 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751659Ab2H2O7p (ORCPT ); Wed, 29 Aug 2012 10:59:45 -0400 In-Reply-To: <503DBBA0.5060108@acm.org> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Bart Van Assche Cc: JBottomley@parallels.com, John Drescher , stable@vger.kernel.org, linux-scsi@vger.kernel.org, Jack Wang On Wed, 2012-08-29 at 06:50 +0000, Bart Van Assche wrote: > On 08/29/12 05:12, Dan Williams wrote: > > John reports: > > BUG: soft lockup - CPU#2 stuck for 23s! [kworker/u:8:2202] > > [..] > > Call Trace: > > [] scsi_remove_target+0xda/0x1f0 > > [] sas_rphy_remove+0x55/0x60 > > [] sas_rphy_delete+0x11/0x20 > > [] sas_port_delete+0x25/0x160 > > [] mptsas_del_end_device+0x183/0x270 > > > > ...introduced by commit 3b661a9 "[SCSI] fix hot unplug vs async scan race". > > Including that call stack in the patch description may create the > misleading impression that this only occurs with the mptsas driver. This > lockup also happens with at least the iSCSI initiator. See also > http://lkml.org/lkml/2012/8/24/340. I don't think it does that. The title is pretty generic, but you're right the impact is potentially all scsi_remove_target() users. > By the way, in order to get a patch in the stable tree the proper "Cc:" > tag should be added in the patch description but the > stable@vger.kernel.org e-mail address should be left out from the > Cc-list of the e-mail with the patch. No, we talked about that at kernel summit. It's ok for the stable@ alias to get a few extra mails. The patch won't be applied until it hits mainline and in the meantime it gives a heads up to the -stable folks, or anyone that wants to follow up on stable patches making their way to mainline. -- Dan