From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965045AbcHNLD2 (ORCPT ); Sun, 14 Aug 2016 07:03:28 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:52001 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964957AbcHNLDZ (ORCPT ); Sun, 14 Aug 2016 07:03:25 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Hannes Reinecke" , "Ewan D. Milne" , "Sergey Senozhatsky" , "Johannes Thumshirn" , "James Bottomley" , "Martin K. Petersen" Date: Sat, 13 Aug 2016 18:42:51 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 018/305] scsi: Add intermediate STARGET_REMOVE state to scsi_target_state In-Reply-To: X-SA-Exim-Connect-IP: 92.40.249.202 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.37-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Johannes Thumshirn commit f05795d3d771f30a7bdc3a138bf714b06d42aa95 upstream. Add intermediate STARGET_REMOVE state to scsi_target_state to avoid running into the BUG_ON() in scsi_target_reap(). The STARGET_REMOVE state is only valid in the path from scsi_remove_target() to scsi_target_destroy() indicating this target is going to be removed. This re-fixes the problem introduced in commits bc3f02a795d3 ("[SCSI] scsi_remove_target: fix softlockup regression on hot remove") and 40998193560d ("scsi: restart list search after unlock in scsi_remove_target") in a more comprehensive way. [mkp: Included James' fix for scsi_target_destroy()] Signed-off-by: Johannes Thumshirn Fixes: 40998193560dab6c3ce8d25f4fa58a23e252ef38 Reported-by: Sergey Senozhatsky Tested-by: Sergey Senozhatsky Reviewed-by: Ewan D. Milne Reviewed-by: Hannes Reinecke Reviewed-by: James Bottomley Signed-off-by: Martin K. Petersen Signed-off-by: Ben Hutchings --- drivers/scsi/scsi_scan.c | 1 + drivers/scsi/scsi_sysfs.c | 2 ++ include/scsi/scsi_device.h | 1 + 3 files changed, 4 insertions(+) --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -320,6 +320,7 @@ static void scsi_target_destroy(struct s struct Scsi_Host *shost = dev_to_shost(dev->parent); unsigned long flags; + BUG_ON(starget->state == STARGET_DEL); starget->state = STARGET_DEL; transport_destroy_device(dev); spin_lock_irqsave(shost->host_lock, flags); --- a/drivers/scsi/scsi_sysfs.c +++ b/drivers/scsi/scsi_sysfs.c @@ -1155,11 +1155,13 @@ restart: spin_lock_irqsave(shost->host_lock, flags); list_for_each_entry(starget, &shost->__targets, siblings) { if (starget->state == STARGET_DEL || + starget->state == STARGET_REMOVE || starget == last_target) continue; if (starget->dev.parent == dev || &starget->dev == dev) { kref_get(&starget->reap_ref); last_target = starget; + starget->state = STARGET_REMOVE; spin_unlock_irqrestore(shost->host_lock, flags); __scsi_remove_target(starget); scsi_target_reap(starget); --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -264,6 +264,7 @@ struct scsi_dh_data { enum scsi_target_state { STARGET_CREATED = 1, STARGET_RUNNING, + STARGET_REMOVE, STARGET_DEL, };