From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 25 Jan 2001 16:50:15 -0500 From: Daniel Eisenbud To: linuxppc-dev@lists.linuxppc.org Subject: Fwd: mesh SCSI bus locks hard on 7500 when burning a CD-R in dao mode Message-ID: <20010125165015.B15827@allspice.cs.swarthmore.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: I asked this in linuxppc-user bothj yesterday and months ago, and have not received any replies, which made me wonder if this list would be a better place to ask. I haven't done any significant kernel hacking, but know C well and am more than happy to try to debug and see if I can fix this, but I'm not sure where to start. I guess the first thing to do should be to boot from a disk on the other SCSI bus and see what errors I get from mesh, since right now everything just freezes hard without any visible diagnostics. Or is there a way, even with a totally frozen SCSI bus (containing the swap partition among other things, though I can of course swapoff before testing this) to tell anything useful about the state of the machine once SCSI is frozen. I have vaguely heard of, but don't know the details of this "magic sysrq" thing. Would that be useful? Please excuse my cluelessness -- any advice that people have is much appreciated! The text of my original message with the details of the problem is below. Thanks, Daniel Eisenbud ----- Forwarded message from Daniel Eisenbud ----- Date: Wed, 24 Jan 2001 22:28:54 -0500 From: Daniel Eisenbud To: linuxppc-user@lists.linuxppc.org Subject: mesh SCSI bus locks hard on 7500 when burning a CD-R in dao mode I have a Powermac 7500 (with a G3 accelerator.) I have replaced the internal CD-ROM with a Yamaha CD-RW drive. This sits on the mesh SCSI bus. I have the mesh driver configured to run at 5 megabytes/second (since I get massive SCSI problems all over the place if I set it to 10.) Under a variety of kernels, from 2.2.15 or so to 2.4.0 from Paul Mackeras's tree, my SCSI setup is generally stable and I can burn CD-R disks just fine in track-at-once mode. However, if I try to burn a disk in disk-at-once mode, either with cdrdao or cdrecord, the SCSI bus appears to silently lock up hard, bringing down my whole machine. Nothing is logged at all, as far as I can tell. Has anyone had this problem before? Does anyone know of a solution? If not, how would I go about debugging this further? Thanks in advance, Daniel Eisenbud -- Daniel E. Eisenbud eisenbud@cs.swarthmore.edu ----- End forwarded message ----- -- Daniel E. Eisenbud eisenbud@cs.swarthmore.edu ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/