On 22 Aug 2002, Eric W. Biederman wrote:
> Jeff Garzik <jgarzik@mandrakesoft.com> writes:
>
> > Eric W. Biederman wrote:
> > > I don't see any checking for the ATA bsy flag before you start sending
> > > commands. I have seen the current IDE code fail too many times if I
> > > boot to fast, because of a lack of this one simple test. So I don't
> > > see how this could be considered a proper probe.
> >
> >
> > There is no ATA bsy flag check at only one point, and that is before EXECUTE
> > DEVICE DIAGNOSTIC is issued. The idea with this command is that it pretty much
> > stomps up and down the ATA bus, trouncing ongoing activity in the process.
>
> The problem is that immediately after bootup ATA devices do not respond until
> their media has spun up. Which is both required by the spec, and observed in
> practice. Which is likely a problem if this code is run a few seconds after
> bootup. Which makes it quite possible the drive will ignore the EXECUTE DEVICE
> DIAGNOSTICS and your error code won't be valid when the bsy flag
> clears. I don't know how serious that would be.
We did POST already.
> I can test and find out but I would rather confine my testing to
> commands that look like they will stay within the realms of
> predictable behavior.
>
> And yes with LinuxBIOS I can reliably boot up fast enough to make this
> problem show up in practice.
>
> Eric
>
Andre Hedrick
LAD Storage Consulting Group
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Fri Aug 23 2002 - 22:00:26 EST