Re: [PATCH v4 02/10] scsi: scsi_debug: Make atomic writes and ZBC emulation mutually exclusive

[Damien Le Moal <dlemoal@kernel.org>]

On 2026/09/18 13:29, Niklas Cassel wrote:
> There are no SMR drives that support atomic writes. Emulating a device
> that supports both is emulating something that a user cannot encounter,
> rather than the drives that exist, and it means maintaining the zone
> handling of a command that no zoned device implements.
> 
> Nothing in the standards forbids the combination. For what would be by
> far the most common case, a host managed SMR drive whose logical block
> size equals its physical block size, there is no problem in the two
> features being combined: the drive vendor only has to give atomic
> writes an alignment that makes sense with regards to ZBC, for instance
> equal to the physical block size. This is therefore a choice not to
> complicate scsi_debug, rather than a restriction that the standards
> impose.
> 
> Refuse the combination at initialisation. If SMR drives that support
> atomic writes ever become a thing, this can be changed back.
> 
> Suggested-by: Damien Le Moal <dlemoal@kernel.org>
> Assisted-by: LLM
> Signed-off-by: Niklas Cassel <cassel@kernel.org>

Looks good.

Reviewed-by: Damien Le Moal <dlemoal@kernel.org>


-- 
Damien Le Moal
Western Digital Research