sh: Fix up restorer in debug_trap exception return path.
There are a few different types of debug trap exceptions, though now that they are all going through a special jump table, the restorer needs to be unified as well. Presently this is falling through the ret_from_fork path, which more or less does the right thing on SH-3/4 whilst being completely unsuitable on MMU-less targets. Ultimately what we want here is a branch through the platform's restore_all directly, without worrying about the retval being clobbered. We can accomplish that through a branch to __restore_all directly, so switch it so we come back from the jump table and branch to the restorer. This fixes up a recursion in the nommu WARN_ON() path, as well as some other userspace nastiness where said recursion caused serious stack corruption. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Showing
Please register or sign in to comment