From 3126976be64bfb4c87297cb022ca815212079aec Mon Sep 17 00:00:00 2001
From: Will Deacon <will.deacon@arm.com>
Date: Fri, 17 May 2013 17:41:22 +0100
Subject: [PATCH] arm64: debug: fix mdscr.ss check when enabling debug
 exceptions

When we take an exception at EL1, we only want to enable debug
exceptions if we're not currently stepping, otherwise we can easily get
stuck in a loop stepping into interrupt handlers.

Unfortunately, the current code tests the wrong bit in the mdscr, so fix
that.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
---
 arch/arm64/include/asm/assembler.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h
index c8eedc604984..5aceb83b3f5c 100644
--- a/arch/arm64/include/asm/assembler.h
+++ b/arch/arm64/include/asm/assembler.h
@@ -82,7 +82,7 @@
 
 	.macro	enable_dbg_if_not_stepping, tmp
 	mrs	\tmp, mdscr_el1
-	tbnz	\tmp, #1, 9990f
+	tbnz	\tmp, #0, 9990f
 	enable_dbg
 9990:
 	.endm