From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-yw0-f193.google.com ([209.85.161.193]:33454 "EHLO mail-yw0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726762AbeG3Ps7 (ORCPT ); Mon, 30 Jul 2018 11:48:59 -0400 Date: Mon, 30 Jul 2018 07:13:45 -0700 From: "tj@kernel.org" To: Bart Van Assche Cc: "mingo@kernel.org" , "jthumshirn@suse.de" , "oleg@redhat.com" , "martin.petersen@oracle.com" , "stable@vger.kernel.org" , "ebiederm@xmission.com" , "linux-scsi@vger.kernel.org" , "hare@suse.com" , "jejb@linux.vnet.ibm.com" Subject: Re: [PATCH, RESEND] Avoid that SCSI device removal through sysfs triggers a deadlock Message-ID: <20180730141345.GC1206094@devbig004.ftw2.facebook.com> References: <20180725173828.2227-1-bart.vanassche@wdc.com> <20180726133527.GU1934745@devbig577.frc2.facebook.com> <4dbd740c0555eb1bfcb4181eeaca5e397b6ab63c.camel@wdc.com> <20180726141435.GV1934745@devbig577.frc2.facebook.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: stable-owner@vger.kernel.org List-ID: Hello, Bart. On Thu, Jul 26, 2018 at 09:57:40PM +0000, Bart Van Assche wrote: ... > @@ -440,11 +445,21 @@ bool sysfs_remove_file_self(struct kobject *kobj, const struct attribute *attr) > return false; > > ret = kernfs_remove_self(kn); > + if (ret && cb) { > + kernfs_break_active_protection(kn); > + cb(kobj, attr, data); > + kernfs_break_active_protection(kn); unbreak? Also, wouldn't it be better to just expose sysfs_break/unbreak and then do sth like the following from scsi? kobject_get(); sysfs_break_active_protection(); do normal sysfs removal; sysfs_unbreak..(); kobject_put(); Thanks. -- tejun