All of lore.kernel.org
 help / color / mirror / Atom feed
From: Bart Van Assche <bart.vanassche@sandisk.com>
To: Christoph Hellwig <hch@infradead.org>,
	Himanshu Madhani <himanshu.madhani@qlogic.com>
Cc: target-devel@vger.kernel.org, nab@linux-iscsi.org,
	giridhar.malavali@qlogic.com, linux-scsi@vger.kernel.org
Subject: Re: [PATCH 12/20] target/tmr: LUN reset cause cmd premature free.
Date: Mon, 4 Jan 2016 08:44:42 +0100	[thread overview]
Message-ID: <568A22EA.10506@sandisk.com> (raw)
In-Reply-To: <20151208024859.GB32255@infradead.org>

On 12/08/2015 03:48 AM, Christoph Hellwig wrote:
> On Mon, Dec 07, 2015 at 07:48:59PM -0500, Himanshu Madhani wrote:
>> From: Quinn Tran <quinn.tran@qlogic.com>
>>
>> During LUN/Target reset, the TMR code attempt to intercept
>> cmds and try to aborted them.  Current code assume cmds are
>> always intercepted at the back end device.  The cleanup code
>> would issue a "queue_status() & check_stop_free()" to terminate
>> the command.  However, when a cmd is intercepted at the front
>> end/Fabric layer, current code introduce premature free or
>> cause Fabric to double free.
>>
>> When command is intercepted at Fabric layer, it means a
>> check_stop_free(cmd_kref--) has been called.  The extra
>> check_stop_free in the Lun Reset cleanup code causes early
>> free.  When a cmd in the Fabric layer is completed, the normal
>> free code adds another another free which introduce a double free.
>>
>> To fix the issue:
>> - add a new flag/CMD_T_SENT_STATUS to track command that have
>>   made it down to fabric layer after back end good/bad completion.
>> - if cmd reach Fabric Layer at Lun Reset time, add an extra
>>   cmd_kref count to prevent premature free.
>
> This seems lke something solved by Bart's abort rewrite in a much nicer
> way.  All this special casing based on magic flags isn't maintainable
> in the long run.

Hello Himanshu and Christoph,

I am currently working on addressing the review comments on my target 
core patch series and will repost that patch series this week.

Bart.

  parent reply	other threads:[~2016-01-04  7:44 UTC|newest]

Thread overview: 51+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-12-08  0:48 [PATCH 00/20] qla2xxx: Patches for target-pending branch Himanshu Madhani
2015-12-08  0:48 ` [PATCH 01/20] qla2xxx: Enable Extended Login support Himanshu Madhani
2015-12-08 15:51   ` Hannes Reinecke
2015-12-08 19:35     ` Himanshu Madhani
2015-12-08  0:48 ` [PATCH 02/20] qla2xxx: Enable Exchange offload support Himanshu Madhani
2015-12-08 15:52   ` Hannes Reinecke
2015-12-08  0:48 ` [PATCH 03/20] qla2xxx: Enable Target counters in DebugFS Himanshu Madhani
2015-12-08 15:52   ` Hannes Reinecke
2015-12-08  0:48 ` [PATCH 04/20] qla2xxx: Add FW resource count " Himanshu Madhani
2015-12-08 15:53   ` Hannes Reinecke
2015-12-08  0:48 ` [PATCH 05/20] qla2xxx: Added interface to send ELS commands from driver Himanshu Madhani
2015-12-08  2:10   ` kbuild test robot
2015-12-08  2:10   ` [PATCH] qla2xxx: fix ifnullfree.cocci warnings kbuild test robot
2015-12-08 15:54   ` [PATCH 05/20] qla2xxx: Added interface to send ELS commands from driver Hannes Reinecke
2015-12-08  0:48 ` [PATCH 06/20] qla2xxx: Delete session if initiator is gone from FW Himanshu Madhani
2015-12-08  1:41   ` kbuild test robot
2015-12-08 15:58   ` Hannes Reinecke
2015-12-08  0:48 ` [PATCH 07/20] qla2xxx: Wait for all conflicts before ack'ing PLOGI Himanshu Madhani
2015-12-08 16:00   ` Hannes Reinecke
2015-12-08  0:48 ` [PATCH 08/20] qla2xxx: Replace QLA_TGT_STATE_ABORTED with a bit Himanshu Madhani
2015-12-08 16:01   ` Hannes Reinecke
2015-12-08  0:48 ` [PATCH 09/20] qla2xxx: Change check_stop_free to always return 1 Himanshu Madhani
2015-12-08  2:33   ` Christoph Hellwig
2015-12-09  6:56   ` Hannes Reinecke
2015-12-10  1:06     ` Quinn Tran
2015-12-08  0:48 ` [PATCH 10/20] qla2xxx: Fix interaction issue between qla2xxx and Target Core Module Himanshu Madhani
2015-12-08  2:37   ` Christoph Hellwig
2015-12-09 22:07     ` Quinn Tran
2015-12-14 10:34       ` Christoph Hellwig
2015-12-14 21:59         ` Quinn Tran
2015-12-09  7:01   ` Hannes Reinecke
2015-12-09 22:41     ` Quinn Tran
2015-12-08  0:48 ` [PATCH 11/20] qla2xxx: Add TAS detection for kernel 3.15 n newer Himanshu Madhani
2015-12-08  2:48   ` Christoph Hellwig
2015-12-09 20:24     ` Quinn Tran
2015-12-14 10:37       ` Christoph Hellwig
2015-12-14 22:00         ` Quinn Tran
2015-12-09  7:02   ` Hannes Reinecke
2015-12-08  0:48 ` [PATCH 12/20] target/tmr: LUN reset cause cmd premature free Himanshu Madhani
2015-12-08  2:48   ` Christoph Hellwig
2015-12-09 20:11     ` Quinn Tran
2016-01-04  7:44     ` Bart Van Assche [this message]
2015-12-09  7:03   ` Hannes Reinecke
2015-12-08  0:49 ` [PATCH 13/20] qla2xxx: Remove dependency on hardware_lock to reduce lock contention Himanshu Madhani
2015-12-08  0:49 ` [PATCH 14/20] qla2xxx: Add irq affinity notification Himanshu Madhani
2015-12-08  0:49 ` [PATCH 15/20] qla2xxx: Add selective command queuing Himanshu Madhani
2015-12-08  0:49 ` [PATCH 16/20] qla2xxx: Move atioq to a different lock to reduce lock contention Himanshu Madhani
2015-12-08  0:49 ` [PATCH 17/20] qla2xxx: Disable ZIO at start time Himanshu Madhani
2015-12-08  0:49 ` [PATCH 18/20] qla2xxx: Set all queues to 4k Himanshu Madhani
2015-12-08  0:49 ` [PATCH 19/20] qla2xxx: Add bulk send for atio & ctio completion paths Himanshu Madhani
2015-12-08  0:49 ` [PATCH 20/20] qla2xxx: Check for online flag instead of active reset when transmitting responses Himanshu Madhani

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=568A22EA.10506@sandisk.com \
    --to=bart.vanassche@sandisk.com \
    --cc=giridhar.malavali@qlogic.com \
    --cc=hch@infradead.org \
    --cc=himanshu.madhani@qlogic.com \
    --cc=linux-scsi@vger.kernel.org \
    --cc=nab@linux-iscsi.org \
    --cc=target-devel@vger.kernel.org \
    --subject='Re: [PATCH 12/20] target/tmr: LUN reset cause cmd premature free.' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.