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Re: [GSoC] Remote kernel debugging over Ethernet

George Georgalis wrote:

Jordan- A few years ago (5?) FreeBSD supported remote kernel
debugging over firewire (don't think it's still supported).
Remote kernel debugging over FireWire has never ceased to work in FreeBSD. Support is even compiled in by default. DragonFly BSD has aquired FreeBSD's IEEE 1394 code and remote kernel debugging abilities too. As NetBSD's FireWire code is based on FreeBSD's, I was very surprised to see NetBSD lacking this ability. As Andrew Doran noted, this support can be ported relatively easily. I even have a desire to do it, however I am fighting with exams now and don't have the necessary time.

I can personally attest that remote kernel debugging over FireWire is addictive :-) It's just that FireWire ports are only seen on select computers/motherboards. You can buy a PCI add-in card with FireWire ports and it will work for kernel debugging, just as you can buy an add-in card with serial ports, but I believe what people really want is something "lazy" - something that works on all computers using only built-in parts.

Seems like an ideal interface for debugging since no software
is required on the remote host, not even a 1394 driver.
Uhm, somebody (the boot loader or the kernel) has to program the IEEE 1394 controller to allow direct access to physical memory. And, by the way, IEEE 1394 controllers conforming to the FireWire OHCI standard can all be handled by a single driver, so once you've got one IEEE 1394 driver, you've got them all, so to speak.

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