Hello Andrew, On Mon, Jul 20, 2009 at 04:14:02PM +0100, Andrew Brampton wrote:
> However, memguard_unguard doesn't work correctly. It first calls > vm_map_protect with a read-write flag. > vm_map_protect correctly updates the vm_map_entry, and then calls > pmap_protect to set the actual pte. > pmap_protect is lazy and notices that we are reducing the protection > on the page and therefore does nothing. It assumes that later that a > page fault will occur, call vm_fault, and then fix up the pte then. As I remember, pmap_protect() is used for removing permissions, it cannot be used (even in initial versions of pmap code) for lowering permissions. pmap_enter() can be used to lower permissions, this is even written in its comments. _______________________________________________ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "freebsd-hackers-unsubscr...@freebsd.org"
