The only problem for me is to find instructions that would build Debian's kernel for LS-VL. The guides that I've tried produces kernels that would not boot on my Linkstation. To debug the cause for the problem, I've attempted to get serial port working, but bailed out after trying to solder 2 tiny bridges on the board that enable the port. They are so damn close together and I'm afraid to mess up.
Yeah, I'm drawing the line at soldering.
Have you considered trying netconsole?
If you build it in to the kernel, you ought to be able to set the default parameters for your situation by hacking the kernel source (this would avoid the need to change the kernel command line supplied by uBoot, for which I haven't found a good guide). Obviously this won't help if uBoot can't boot the kernel, but it just depends where your boot is dying.
In my case, the red LED comes on immediately, so I'm guessing that means uBoot couldn't even manage to hand off to the new kernel (since the Debian kernel wouldn't know how to turn on the red LED if something went wrong) and that netconsole wouldn't help, though I may try it anyway.
Thanks a lot for the suggestions on compiling the Buffalo kernel package. I will give it a try.