Re: [PATCH v16 05/26] blk-zoned: Fix a deadlock triggered by unaligned writes

Damien Le Moal
2025-01-10T05:07:57Z

On 1/10/25 04:11, Bart Van Assche wrote:
> On 11/18/24 6:57 PM, Damien Le Moal wrote:
>> And we also have the possibility of torn writes (partial writes) with
>> SAS SMR drives. So I really think that you cannot avoid doing a
>> report zone to recover errors.
> (replying to an email of two months ago)
>
> Hi Damien,
>
> How about keeping the current approach (setting the
> BLK_ZONE_WPLUG_NEED_WP_UPDATE flag after an I/O error has been observed)
> if write pipelining is disabled and using the wp_offset_compl approach
> only if write pipelining is enabled? This approach preserves the
> existing behavior for SAS SMR drives and allows to restore the write
> pointer after a write error has been observed for UFS devices. Please
> note that so far I have only observed write errors for UFS devices if I
> add write error injection code in the UFS driver.

If you get write errors, they will be propagated to the user (f2fs in this case
I suspect) which should do a report zone to verify things. So I do not see why
this part would need to change.

> Thanks,
>
> Bart.
>

--
Damien Le Moal
Western Digital Research