Re: [PATCH] Fix for hang of Ordered task in TCM

From: Nicholas A. Bellinger
Date: Tue May 24 2016 - 01:47:52 EST

Hi Bryant,

On Mon, 2016-05-23 at 19:17 -0400, Bryant G Ly wrote:
> Quoting "Nicholas A. Bellinger" <nab@xxxxxxxxxxxxxxx>:
> <SNIP>
> >
> > So AFAICT for delayed commands, the above patch ends up skipping these
> > three checks subsequently when doing __target_execute_cmd() directly
> > from target_restart_delayed_cmds(), no..?
> >
> > After pondering this some more, what about moving these checks into
> > __target_execute_cmd() to handle both target_core_transport.c cases
> > instead..?
> >
> > We'll also need a parameter for internal COMPARE_AND_WRITE usage
> > within compare_and_write_callback(), to bypass checks upon secondary
> > ->execute_cmd() WRITE payload submission after READ + COMPARE has
> > completed successfully.


> Looks good to me.

Thanks for the review!

> Nick just to let you know I've been working with
> Mike on VSCSI Target Fabric and we need this patch in kernel 4.4 do
> you know of the process in getting that there?

So pending a bit more list feedback + testing across multiple fabric
drivers, it's been added for the moment to target-pending/queue as post
-rc1 material.

As it merged into target-pending/master next week, the extra stable CC'
can be added to be picked up for linux-4.4.y stable and friends.

Also AFAIK, we've not had reports of other SCSI host environments
triggering this bug, but it's still a good idea to consider it for
linux-3.x.y backport at some point as well.