Yay ! Let's map everything uncached from now on! For great justice!
[I was tempted to write some stuff about how keyboard keycode translation
works in wscons, but it's not worth my time]
Miod
You don't have to map keyboard map uncached, just change the way code is
written --- instead of
x = a[i]
you write something like
x = 0;
for (j = 0; j < sizeof a/sizeof *a; j++) x |= a[j] & (-(i ^ j) >> 31) - 1;
Keyboard reading code is in sys/dev/wscons/wskbdutil.c, function
wskbd_get_mapentry. It scans the keymap linearly until it finds the key
pressed. So, by amount of L2 cache lines eaten, an attacker could tell
which class of keys was pressed.
Mikulas
