Re: [PATCH] nvme: honor NVME_QUIRK_DEALLOCATE_ZEROES for unmap Write Zeroes

[Zhang Yi]

Hi Robert,

On 3/11/2026 1:14 AM, Robert Pang wrote:
> Hi Christoph
> 
> On Fri, Mar 6, 2026 at 6:24 AM Christoph Hellwig <hch@xxxxxx> wrote:
>>
>> On Thu, Mar 05, 2026 at 12:27:32PM -0800, Robert Pang wrote:
>>> However, certain devices already use the NVME_QUIRK_DEALLOCATE_ZEROES quirk to
>>> indicate that they deterministically return zeroes after a deallocate/discard
>>
>> Those certain devices are completely obsolete first generation Intel
>> SSDs.
>>
>>> Update nvme_update_disk_info() to allow the presence of the DEALLOCATE_ZEROES
>>> quirk (combined with DSM support) to set max_hw_wzeroes_unmap_sectors to enable
>>
>> No. This was a hack that got sneaked in in the first days of the nvme
>> driver and never should have been there.  It most certainly should not
>> be extended to any new functionality.
>>
> 
> Thank you for your review and for providing the historical context
> regarding this quirk. Given these insights, we can discard this patch
> proposal.
> 

I just wonder if you have such hardware and use cases, or if you simply
want to supplement this feature for those corner devices?

Best regards
Yi.

> Best regards
> Robert Pang