Ronald G Minnich <[EMAIL PROTECTED]> writes:

> for PCI mapping, I like the idea of leaving "red zones" between
> memory-mapped I/O spaces. One page each. There are unreadable/unwriteable
> regions. A good way to catch driver screwups that might otherwise lead to
> very strange and untracable errors.  I've been burned by this on standard
> BIOSes more than once.

Hmm.  In the kernel you already have to call ioremap, which
is essentially a vmalloc but using memory from pci-io space.  And 
last I looked this implemented the "red zones" using virtual addresses
instead of physicall addresses.  

I don't see where a BIOS comes in here at all.  Especially when you are
talking about OS level drivers.

My concern is to pack the pci resources as tight as is reasonable so
when you plug in dolphin, or quadrics cards you don't loose a gigabyte
of ram.

I don't have a problem in principle with redzones I just don't see how
they make any difference from the bios side.

Eric

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