According to memtest86, there is a persistent single bit error in my MacBook Pro's 16GB of DDR RAM.
Since the error is in the second half of the physical address space, I can work around the problem by running sudo nvram boot-args="maxmem=8192". However, this is a bit of a waste of the other half - a working 8GB minus one bit.
Is there a way, perhaps with an Open Firmware command or configuration, or a special boot-args option (e.g. nvphash?), that will allow me to mark as unusable just the small section that contains the bit error?