Sorry if this bugs anyone, but I'm learning things here. What I would expect the kernel to do is this:
system_call_data_prep (userdata, size){ if !4G/4G { for each page from userdata to userdata+size { if the page is swapped out, swap it in if the page is not owned by the user process, return -ENOWAYMAN otherwise, lock the page } return userdata; } else { //kernel land and userland are mutually exclusive copy the data into kernel land return kernelland_copy_of_userdata; } } (And then the syscall would need to run the opposite function sys_call_data_unprep to unlock pages.) Hmm, maybe that interface sucks. Is it anything close to that? -- The best is the enemy of the good -- Voltaire The Good Enough is the enemy of the Great -- Me http://www.hacksaw.org -- http://www.privatecircus.com -- KB1FVD - 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/