From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 30 Jan 2001 16:57:10 -0500 From: Daniel Eisenbud To: Michael Schmitz Cc: linuxppc-dev@lists.linuxppc.org Subject: Re: mesh SCSI bus locks hard on 7500 when burning a CD-R in dao mode Message-ID: <20010130165710.B22219@allspice.cs.swarthmore.edu> References: <20010130163538.A22219@allspice.cs.swarthmore.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: ; from schmitz@zirkon.biophys.uni-duesseldorf.de on Tue, Jan 30, 2001 at 10:46:06PM +0100 Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: On Tue, Jan 30, 2001 at 10:46:06PM +0100, Michael Schmitz wrote: > > > The big question: why does this particular command time out in the first > > > place? Does the target expect more data to be sent? Does the target just > > > crash and fails to release the bus? It seems to work on other host > > > adapters, doesn't it? > > > > There's a report of excatly the same failure mode on mac53c94 with a > > different brand (Sony, as opposed to Yamaha on my MESH) of DVD drive. > > Please send a detailed description on how to reproduce this bug by PM. > I'll try to look into that on my Lombard, and in case I can get the > required binaries for m68k I'd also test on an old Quadra with 53c9x > SCSI. Basically, any time I have used cdrdao to write a disc, or cdrecord with the -dao flag, the SCSI bus has locked up, under kernels from 2.2.15pre3 or so to a recent 2.4 from the bk tree. I'm tempted to see whether I can write a short program using the sg stuff to just send the "send_cue_sheet" command to the CD-RW and see if it locks up, but I haven't had a chance to look into it yet. > Does the bug happen only with DVD writers, or regular CD writers? Aargh, sorry, when I said "DVD" above it was a complete thinko. I have a Yamaha CD-RW drive (the model number is something wit 8424 in it, I can get exact details when I get home.) The report with the mac53c94 driver was a Sony CD-R or CD-RW drive -- I've exchanged email with the guy who reported it and can ask for the details if you'd like. I have no idea if it would fail with a DVD writer, but all the cases I've seen have been CD writers. (This is why it's not a good idea to wait until late afternoon to have coffee, and why if I do so, I should refrain from writing email until after I have found some.) :-) > > So the only points in common seem to be that the DVD drives are running > > on mac hardware and that the drivers are written by Paul Mackerras. :-) > > I don't at all mean to impugn Paul's coding ability, which is obviously > > excellent, but the fact that he wrote both the drivers may mean that > > they share lots of code and possibly share the same bug. > > If so, the bug should have propagated to the m68k 53c9x driver. Wouldn't > be the 53c9x first weirdness - I never got it to accept a DAT drive (old > DDS-1, possibly Apple) without blowing up. It would be great if you could check this out. > It might be something PPC specific as well and have nothing to do with > Paul's drivers. This is why I asked in a previous email whether anyone had ever burned a disk in DAO mode successfully on a pmac or in fact on any powerpc machine, but I've received no responses. Hmm, maybe I should try to conduct a quick survey of this on linuxppc-user and/or debian-powerpc. -Daniel -- Daniel E. Eisenbud eisenbud@cs.swarthmore.edu ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/