My .config for -bk6 is attached.  The same error occurs with the -mm5 tree too.

Update:  Ok, I figured out the problem.  I didn't have "Generic PCI bus-master 
DMA support" enabled.  From reading its description I didn't think I needed it 
because I have no IDE drives on my system (I need IDE for 2 ATAPI devices, my 
hard drive is SCSI).  On reflection, I may not need "PCI IDE chipset support" at 
all either.

In any event there seems to be a missing dependency here.  CONFIG_BLK_DEV_IDEPCI 
("PCI IDE chipset support") controls whether drivers/ide/setup_pci.c is 
compiled.  That file calls ide_setup_dma(), but this function is in 
drivers/ide/ide_dma.c which is controlled by CONFIG_BLK_DEV_IDEDMA_PCI which is 
a *suboption* of IDEPCI.  In other words, from my understanding of this, the 
latter config option, IDEDMA_PCI, should be automatically *required* if the 
first config option, IDEPCI, is selected.

Of course, I could be reading this wrong, I'm just providing this FWIW.  :)

HTH,
Ed