powerpc: Hook in new transactional memory code

This hooks the new transactional memory code into context switching, FP/VMX/VMX
unavailable and exception return.

Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 32 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 5c30469..f9b751b 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -1029,6 +1029,38 @@ void __kprobes program_check_exception(struct pt_regs *regs)
 		_exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip);
 		return;
 	}
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	if (reason & REASON_TM) {
+		/* This is a TM "Bad Thing Exception" program check.
+		 * This occurs when:
+		 * -  An rfid/hrfid/mtmsrd attempts to cause an illegal
+		 *    transition in TM states.
+		 * -  A trechkpt is attempted when transactional.
+		 * -  A treclaim is attempted when non transactional.
+		 * -  A tend is illegally attempted.
+		 * -  writing a TM SPR when transactional.
+		 */
+		if (!user_mode(regs) &&
+		    report_bug(regs->nip, regs) == BUG_TRAP_TYPE_WARN) {
+			regs->nip += 4;
+			return;
+		}
+		/* If usermode caused this, it's done something illegal and
+		 * gets a SIGILL slap on the wrist.  We call it an illegal
+		 * operand to distinguish from the instruction just being bad
+		 * (e.g. executing a 'tend' on a CPU without TM!); it's an
+		 * illegal /placement/ of a valid instruction.
+		 */
+		if (user_mode(regs)) {
+			_exception(SIGILL, regs, ILL_ILLOPN, regs->nip);
+			return;
+		} else {
+			printk(KERN_EMERG "Unexpected TM Bad Thing exception "
+			       "at %lx (msr 0x%x)\n", regs->nip, reason);
+			die("Unrecoverable exception", regs, SIGABRT);
+		}
+	}
+#endif
 
 	/* We restore the interrupt state now */
 	if (!arch_irq_disabled_regs(regs))