Re: [PATCH] libata-eh copy result_tf flags from outgoing tf

[Tejun Heo <htejun@gmail.com>]

Mark Lord wrote:
> Fix mis-reporting of NCQ errors by copying tf->flags to result_tf->flags
> in libata-eh.  This allows ata_gen_ata_sense() to report the failed
> block number correctly to SCSI after a media error during NCQ.
> 
> This patch may also be a candidate for backporting to earlier kernels.
> Without this fix, SCSI will fail I/O on the entire request rather
> than just the bad sector.  That can be bad for a request that was
> merged from many independent read reads from different tasks.
> 
> Signed-off-by: Mark Lord <mlord@pobox.com>
> 
> --- upstream/drivers/ata/libata-eh.c    2008-04-18 09:31:15.000000000 -0400
> +++ linux/drivers/ata/libata-eh.c    2008-04-23 16:25:38.000000000 -0400
> @@ -1402,6 +1402,7 @@
>     /* we've got the perpetrator, condemn it */
>     qc = __ata_qc_from_tag(ap, tag);
>     memcpy(&qc->result_tf, &tf, sizeof(tf));
> +    qc->result_tf.flags = qc->tf.flags;

Maybe it's better to set ATA_TFLAG_LBA48 | ATA_TFLAG_ISADDR | 
ATA_TFLAG_DEVICE?  After all, all fields are available after that memcpy().

Thanks for fixing this.

-- 
tejun