Was there a dmesg out there somewhere?
With 4G of RAM, you probably have some of it above the 4GB mark (because
of RAM remapping etc, and the PCI decode hole in the low 4GB). It does
sound like this is a DMA problem, and your controller cannot correctly DMA
to the upper 4GB.
So what controller/driver, what's the dmesg, and let's see if we can fix
it by adding a DMA mask to it to limit it to the low 32 bits.
Linus
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