MIPS: Allow kernel to use coprocessor 2

Kernel threads should be able to use COP2 if the platform needs it.
Do not call die_if_kernel() for a coprocessor unusable exception if
the exception due to COP2 usage.  Instead, the default notifier for
COP2 exceptions is updated to call die_if_kernel.

Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Cc: ddaney.cavm@gmail.com
Patchwork: https://patchwork.linux-mips.org/patch/5415/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This commit is contained in:
Jayachandran C 2013-06-10 06:30:01 +00:00 committed by Ralf Baechle
parent 2c952e06e4
commit 83bee792d7

View File

@ -1056,15 +1056,9 @@ static int default_cu2_call(struct notifier_block *nfb, unsigned long action,
{
struct pt_regs *regs = data;
switch (action) {
default:
die_if_kernel("Unhandled kernel unaligned access or invalid "
die_if_kernel("COP2: Unhandled kernel unaligned access or invalid "
"instruction", regs);
/* Fall through */
case CU2_EXCEPTION:
force_sig(SIGILL, current);
}
force_sig(SIGILL, current);
return NOTIFY_OK;
}
@ -1080,10 +1074,11 @@ asmlinkage void do_cpu(struct pt_regs *regs)
unsigned long __maybe_unused flags;
prev_state = exception_enter();
die_if_kernel("do_cpu invoked from kernel context!", regs);
cpid = (regs->cp0_cause >> CAUSEB_CE) & 3;
if (cpid != 2)
die_if_kernel("do_cpu invoked from kernel context!", regs);
switch (cpid) {
case 0:
epc = (unsigned int __user *)exception_epc(regs);