[Drbd-dev] [PATCH 12/23] sd: handle REQ_UNMAP

[hch at lst.de]

On Thu, Mar 30, 2017 at 10:19:55PM -0400, Martin K. Petersen wrote:
> > If you manually change the provisioning mode to WS10 on a device that
> > must use WRITE SAME (16) to be able to address all blocks you're already
> > screwed right now, and with this patch you can screw yourself through
> > the WRITE_ZEROES path in addition to the DISCARD path.
> 
> Oh, I see. We only had the LBA sanity check in place for write same, not
> for discard.

And btw, I'd be happy to add such a check, I'd just rather keep it out
of this patch.  It might be a good idea if you give it a turn after
this series given that you have all the devices that have weird
provisioning modes while I don't..