Re: Bus error in macscsi_pread

["Brian Morris" <cymraegish@gmail.com>]

On 11/21/06, Brad Boyer <flar@allandria.com> wrote:
> On Tue, Nov 21, 2006 at 11:41:31PM -0500, De Served wrote:
> > Trying to get Sarge installed on an LCIII.   I'm using the following
> > command line arguments:   root=/dev/ram ramdisk_size=13000
> >
> > Everything seems to work quite well until I get the bus error.   This is
> > the output:
> >
> > SCSI device sda: 333936 512-byte hdwr sectors (171 MB)
> > Bus error in macscsi_pread
> > sd 0:0:0:0: switching to slow handshake
> >
> > and the boot process freezes at this point.  Any ideas?
>
> I didn't realize this bug hadn't been fixed yet. The pseudo-DMA
> routines in the mac_scsi driver got broken at some point, which
> means that you have to disable that feature to get working drive
> access. It also means your disk performance will go down to some
> very painfully slow speeds. This came up recently on the mailing
> list and some suggestions were made. The command line addition I
> suggested was this one:
>
> mac5380=-1,-1,-1,-1,0
>
> This will tell the driver not to attempt pseudo-DMA at all.
>
> My main test box is a IIfx, which has this feature disabled
> in the code because the scsi chip is just a little different
> and only works with the slow code path.
>
>         Brad Boyer
>         flar@allandria.com
i only had this problem on my lcIII when i was working with the 2.6.17 kernels.

What is this a 170mb disc, besides that is tiny
it is probably way too old, may as well go back to kernel 1.0. that thing needs
pulled (IMHO).