MacbookPro8,2 crashing in the USB stack on startup

[david.given]

I’ve got a Macbook Pro 8,2 which I’ve tried Haiku on. It’s super unhappy.

For every boot, one of four things happens:

• it boots relatively normally.
• it takes a really long time to boot (usually waiting for ~20s at the Card icon on the boot screen), and then continues. I get a semi-working system with some USB devices non-functional. The MBP has the keyboard and touchpad connected via USB internally, so occasionally this makes the machine simply noninteractive. Enabling debug tracing shows lots of errors during USB initialisation.
• it crashes into KDL on boot. (With the keyboard unresponsive, sadly.)

I have a picture of the last; it's showing some of the USB debug tracing from the second last.

The machine works fine in Linux and in OSX, so I don't believe it's a hardware issue; this era of MBP is pretty cursed due to flaky solder joints, so it's always an option. My guess is that something about Apple's weird hardware is provoking an edge case causing the driver not to be able to initialise the bus, at which point it goes into a weird state, and then it crashes on unload.

Is there a way to get the full debug trace off the machine? MBPs don't have serial ports...

[david.given]

KDL screenshot

[korli]

Probably checking that fNode is non null at ​https://cgit.haiku-os.org/haiku/tree/src/add-ons/kernel/bus_managers/usb/Device.cpp#n342 should be safe.