ARM: 7497/1: hw_breakpoint: allow single-byte watchpoints on all addr…

…esses

Breakpoint validation currently fails for single-byte watchpoints on
addresses ending in 11b. There is no reason to forbid such a watchpoint,
so extend the validation code to allow it.

Cc: Ulrich Weigand <Ulrich.Weigand@de.ibm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/kernel/hw_breakpoint.c

@@ -610,13 +610,14 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp)
 		/* Aligned */
 		break;
 	case 1:
-		/* Allow single byte watchpoint. */
-		if (info->ctrl.len == ARM_BREAKPOINT_LEN_1)
-			break;
 	case 2:
 		/* Allow halfword watchpoints and breakpoints. */
 		if (info->ctrl.len == ARM_BREAKPOINT_LEN_2)
 			break;
+	case 3:
+		/* Allow single byte watchpoint. */
+		if (info->ctrl.len == ARM_BREAKPOINT_LEN_1)
+			break;
 	default:
 		ret = -EINVAL;
 		goto out;