tree 17f6b1f4f0e09330f108f0a9ffc5b30aa9166da1
parent 75c92acdd5b19a5e3536ed670e1122d73c635b4a
author Paul Mundt <lethal@linux-sh.org> 1159335482 +0900
committer Paul Mundt <lethal@linux-sh.org> 1159335482 +0900

sh: Fix fatal oops in copy_user_page() on sh4a (SH7780).

We had a pretty interesting oops happening, where copy_user_page()
was down()'ing p3map_sem[] with a bogus offset (particularly, an
offset that hadn't been initialized with sema_init(), due to the
mismatch between cpu_data->dcache.n_aliases and what was assumed
based off of the old CACHE_ALIAS value).

Luckily, spinlock debugging caught this for us, and so we drop
the old hardcoded CACHE_ALIAS for sh4 completely and rely on the
run-time probed cpu_data->dcache.alias_mask. This in turn gets
the p3map_sem[] index right, and everything works again.

While we're at it, also convert to 4-level page tables..

Signed-off-by: Paul Mundt <lethal@linux-sh.org>