I'm having problems with the pci_dma_read() function. When using a Mac OS X guest, the data that this function returns is all zeros. After doing a lot of instruction tracing, I tracked the problem to a function called phys_page_find(). It always returns §ions[PHYS_SECTION_UNASSIGNED]. What I would like to know is what is an unassigned section? How is memory suppose to be assigned?
The pci_dma_read() function call I'm tracking takes place in rtl8139.c in case anyone would like to know.