Re: Kernel virtual memory?

Jochen Karrer (
Thu, 7 Aug 1997 17:58:04 +0200 (MET DST)


> Could kernel use virtual memory hardware to make non-linear chunks of
> memory to look linear? It seems to me that it could solve the problems
> with memory fragmentation and DMA memory allocation.

The memory management is done in the CPU, so only the CPU sees
this virtual address. PCI-BUS- and ISA-Address is on intel architecture
the same address like the physical address.

> DMA memory could be allocated by moving allocated blocks away from the
> lower 16MB, and other parts of kernel could be made happy by changing the
> page tables accordingly.
> So, is this possible/feasible/too ugly to implement?
Not possible.