On Wed, 26 Aug 2020 15:24:26 +0800, Luo Jiaxing wrote:
> We found that it will fail every time when set feature to SATA disk by
> "sdparm -s WCE=0 /dev/sde".
>
> After checking protocol, we know that MODE SELECT is the SCSI command for
> setting WCE, and it do not exist in the SATA protocol. Therefore, this
> commands are encapsulated in the SET FEATURE command in SATA protocol.
> The difference is that the MODE SELECT command sent to SAS disk contains
> data and is sent through the DMA. But when send to SATA disk through
> SET FEATURE command, it does not contain data.
>
> [...]
Applied to 5.9/scsi-fixes, thanks!
[1/1] scsi: libsas: Set data_dir as DMA_NONE if libata marks qc as NODATA
https://git.kernel.org/mkp/scsi/c/53de092f47ff
--
Martin K. Petersen Oracle Linux Engineering
