On Mon, 2006-07-24 at 05:14 -0400, Mark Hounschell wrote: > Thomas Petazzoni wrote: > > Hi, > > > > Le Fri, 21 Jul 2006 09:10:47 -0400, > > Mark Hounschell <markh@xxxxxxxxxx> a écrit : > > > >>> Use copy_from_user() in the kernel. It will automagically fetch the > >>> page from swap or from anywhere it is. > >> Wouldn't mlockall used in the application do it? > > > > It would do it, but that's completely useless to mlock() an entire > > application just for this reason. > > > > copy_from_user() and copy_to_user() are specifically designed to handle > > page faults that may occur during the copy. they do more though: they recognize that the kernel and userspace may run in a separate address space and they bridge that. To underline that: even if you mlock() the memory, you still cannot dereference userspace pointers in the kernel, you STILL *have* to use copy_*_user() api set (includes get_user/put_user etc) -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
