I'm seeing the "DMA: Out of SW-IOMMU space for 4224 bytes at device 0000:0b:00.0" message too, and have also reverted to the ath_pci (madwifi) driver.
This is on a MacBook Pro version 3.1 without any peripherals attached. I did increase the memory to 4 GB, but other than that it is all stock hardware.
I'm seeing the "DMA: Out of SW-IOMMU space for 4224 bytes at device 0000:0b:00.0" message too, and have also reverted to the ath_pci (madwifi) driver.
This is on a MacBook Pro version 3.1 without any peripherals attached. I did increase the memory to 4 GB, but other than that it is all stock hardware.