From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Martin K. Petersen" <martin.petersen@oracle.com>
Subject: Re: [PATCH] dm-raid: add RAID discard support
Date: Thu, 02 Oct 2014 21:12:13 -0400
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>>>>> "Heinz" == Heinz Mauelshagen <heinzm@redhat.com> writes:

Heinz> BTW: we're referring to SSD discard_zeroes_data issues only so
Heinz> far it seems?  Can we be sure that SCSI unmap with the TPRZ bit
Heinz> set will always return zeroes on reads for arbitrary storage
Heinz> devices?

Only if we used WRITE SAME to discard.

-- 
Martin K. Petersen	Oracle Linux Engineering