14. Debugging the ftape driver

14.1 The kernel/ftape crashes on me when I do `...' - is that a bug?

No, that is a feature ;‐)

Seriously, reliable software do not crash. Especially kernels do not or rather should not crash. If the kernel crashes upon you when you are running ftape, and you can show that it is ftape that is messing things up, regard it as a Bug That Should Be Fixed. Mail the details to the maintainer (<heine@math1.rwth-aachen.de>) and to the tape list.

14.2 OK, it's a bug ...ehhh... feature - How do I submit a report?

First, make sure you can reproduce the problem. Spurious errors are a pain in the ass, since they are just about impossible to hunt down :-/ This is a quick check list:

• Kernel version, and patches applied
• ftape version
• tape drive model / manufacturer
• Expansion bus type (EISA, ISA, PCI, or VL-bus)
• What you did to expose the problem
• What went wrong on your system.
• Do not delete the kernel and the ftape.o file. I might want you run try some patches out or run a different test on your system.

Increase the tracing level to 4 or 5 and run the command that caused problems again (don't do it if your fear that you loose data or damage your hardware, there is absolutely no warranty for neither data loss nor hardware damage caused by ftape, remember this). Increasing the trace level beyond 5 probably doesn't make any sense as it affects the timing of the driver in a way that it doesn't work well any more. Get the tracing data from the kernel log or /proc/kmsg, depending on where you harvest your error messages. Try to look at what ftape spews out at you. It may look in-comprehensible to you at first, but you can get valuable information from the logfile. Most messages have a function name prepended, to make it easier to locate the problem. Look through the source, don't just cry ``WOLF!'', without giving it a try. If your version of the kernel (or ftape for that matter), is ``old'', when compared to the newest version of the kernel, try to get a newer (or even the newest) kernel and see if the problem goes away under the new kernel. When you post your problem report, include the information about ftape version, kernel version, expansion bus type (ISA, VL-bus, PCI or EISA), bus speed, floppy controller, and tape drive. State exactly what you did, and what happened on your system. Some people have experienced that ftape would not run in a PCI based box, but ran flawlessly in a normal ISA based 386DX machine (see section Getting PCI motherboards to work with <tt/ftape/ on PCI machines above)

Also, please think of the poor souls who actually pay the their Internet access (like me): avoid posting a (huge) log from the ftape run, without reason. Instead, you could describe the problem, and offer to send the log to the interested parties.

Send your bug report to <linux-tape@vger.rutgers.edu>. You might also want to mail the bug to <heine@math1.rwth-aachen.de>.