On Tue, Oct 02, 2012 at 09:44:16PM -0700, H. Peter Anvin wrote: > We *always* expose the I/O regions to /dev/mem. That is what /dev/mem > *does*. The above is an exception (which is really obsolete, too: we > should simply disallow access to anything which is treated as system > RAM, which doesn't include the BIOS regions in question; the only reason > we don't is that some versions of X take a checksum of the RAM in the > first megabyte as some kind of idiotic random seed.)
Oh, right, got you. In that case I think we potentially need a finer-grained check on EFI platforms - the EFI memory map is kind enough to tell us the difference between unusable regions and io regions, and we could avoid access to the unusable ones. -- Matthew Garrett | [email protected] -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
