On Thu, 2017-05-11 at 08:26 +0200, hch@xxxxxx wrote: > On Wed, May 10, 2017 at 09:50:35PM -0700, Nicholas A. Bellinger wrote: > > 1) Expose a block_device or request_queue bit to signal 'real LBPRZ' > > support up to IBLOCK, in order to maintain SCSI target feature > > compatibility. > > No way. If you want to zero use REQ_OP_WRITE_ZEROES.. Yes, I understand that part and it's what the earlier conversion of IBLOCK to use blkdev_issue_zeroout() already does. Once the blkdev_issue_zeroout() conversion is in place then LBPRZ can always be set to one for IBLOCK using blkdev_issue_zeroout(). The point is this is not in -rc1, which as-is breaks LBPRZ compat for a release.