Re: [PATCH] scsi_lib.c: continue after MEDIUM_ERROR

[Mark Lord <liml@rtr.ca>]

James Bottomley wrote:
> On Wed, 2007-01-31 at 12:57 -0500, Mark Lord wrote:
> > Alan wrote:
> > > > When libata reports a MEDIUM_ERROR to us, we *know* it's non-recoverable,
> > > > as the drive itself has already done internal retries (libata uses the
> > > > "with retry" ATA opcodes for this).
> > > This depends on the firmware. Some of the "raid firmware" drives don't
> > > appear to do retries in firmware.
> > One way to tell if this is true, is simply to time how long
> > the failed operation takes.  If the drive truly does not do retries,
> > then the media error should be reported more or less instantly
> > (assuming drive was already spun up).
>
> Well, the simpler way (and one we have a hope of implementing) is to
> examine the ASC/ASCQ codes to see if the error is genuinely unretryable.

My suggestion above was not for a kernel fix,
but rather just as a way of determining if drives
which claim "no retries" actually do them or not.  :)

> I seem to have dropped the ball on this one in that the scsi_error.c
> pieces of this patch
>
> http://marc.theaimsgroup.com/?l=linux-scsi&m=116485834119885
>
> I thought I'd applied.  Apparently I didn't, so I'll go back and put
> them in.

Good.  That would be a useful supplement to the patch I posted here.

Cheers
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