Re: [PATCH] nvme/pci: Use Discard instead of Write Zeroes on SK hynix SC300

From: Christoph Hellwig
Date: Fri Apr 17 2020 - 08:59:36 EST


On Fri, Apr 17, 2020 at 04:36:41PM +0800, Kai-Heng Feng wrote:
> After commit 6e02318eaea5 ("nvme: add support for the Write Zeroes
> command"), SK hynix SC300 becomes very slow with the following error
> message:
> [ 224.567695] blk_update_request: operation not supported error, dev nvme1n1, sector 499384320 op 0x9:(WRITE_ZEROES) flags 0x1000000 phys_seg 0 prio class 0]
>
> Use quirk NVME_QUIRK_DEALLOCATE_ZEROES to workaround this issue.

Do you have a written guarantee from SK Hynix that it will always zero
all blocks discarded?