I turned off /dev/kmem access and X would no longer work on my centrino-based laptop. Actually what I should say is I turned off /dev/kmem access and then installed X and was surprised to see it not working, until I got around to checking dmesg. Anyway on my system the following:
!(offset == 0xc0000 && ((vma->vm_end - vma->vm_start) <= 0xf0000) in grsec_mem.c fixed the first /dev/[k]mem access...
but then it bombed trying to map 0xb7f4b000...0xb7f4c000
at this point I gave up adding more offsets, I'm out of my element here already. Disable privileged I/O is *NOT* enabled, btw. This is 2.6.11 gentoo hardened.
Anyway I'll just turn that feature off but I thought I'd pass the word on to more knowledgable people, in the event that there is a fix or whatever.
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