On Thu, 15 Feb 2007 23:08:02 -0800 Jeremy Fitzhardinge <[email protected]> wrote:
> Andrew Morton wrote:
> > This won't work when CONFIG_PREEMPT=y. The pagefault handler will see
> > in_atomic() and will scram.
> >
>
> Is there some other way to get the pagetable populated for the address
> range?
>
If you really need to run atomically, that gets ugly. Even of one were to
run handle_mm_fault() by hand, it still needs to allocate memory.
Two ugly options might be:
a) touch all the pages, then go atomic, then touch them all again. If
one of them faults (ie: you raced with swapout) then go back and try
again. Obviously susceptible to livelocking.
b) Do get_user_pages() against all the pages, then go atomic, then do
put_page() against them all. Of course, they can immediately get
swapped out.
But that function's already racy against swapout and I guess it works OK.
I don't have clue what it is actually trying to do, so I'm guessing madly
here.
-
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/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
