nvme reservation commands during controller reset

[Engel, Amit]

We saw that in case of path error, nvme reservation cmds does not get error handling.
This is true via the blk layer as well as nvme-cli.

We are working on implementing nvmeof stack and 
this current behavior is blocking our host from running nvme reservation cmds during path error.

-----Original Message-----
From: Christoph Hellwig <hch at infradead.org> 
Sent: Monday, August 10, 2020 3:41 PM
To: Keith Busch
Cc: Engel, Amit; Anner, Ran; linux-nvme at lists.infradead.org
Subject: Re: nvme reservation commands during controller reset


[EXTERNAL EMAIL] 

On Sun, Aug 09, 2020 at 10:10:16AM -0600, Keith Busch wrote:
> On Wed, Aug 05, 2020 at 07:14:22AM +0000, Engel, Amit wrote:
> > What is the reason for setting REQ_FAILFAST_DRIVER flag in nvme_alloc_request ?
> > The original intention was to mark only sync cmds as failfast ?
> 
> Special requests don't get generic error handling. The caller gets to 
> decide how to handle it.

Although I wonder if we want to allow to opt in into the normal retries, as for some cases that might actually make sense.