From e89c0d7090c54d7b11b9b091e495a1ae345dd3ff Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Tue, 5 Apr 2011 13:57:53 +0100 Subject: [PATCH] ARM: 6864/1: hw_breakpoint: clear DBGVCR out of reset The DBGVCR, used for configuring vector catch debug events, is UNKNOWN out of reset on ARMv7. When enabling monitor mode, this must be zeroed to avoid UNPREDICTABLE behaviour. This patch adds the zeroing code to the debug reset path. Cc: stable Reported-by: Stepan Moskovchenko Signed-off-by: Will Deacon Signed-off-by: Russell King --- arch/arm/kernel/hw_breakpoint.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c index 8dbc126f715..87acc25d7a3 100644 --- a/arch/arm/kernel/hw_breakpoint.c +++ b/arch/arm/kernel/hw_breakpoint.c @@ -868,6 +868,13 @@ static void reset_ctrl_regs(void *info) */ asm volatile("mcr p14, 0, %0, c1, c0, 4" : : "r" (0)); isb(); + + /* + * Clear any configured vector-catch events before + * enabling monitor mode. + */ + asm volatile("mcr p14, 0, %0, c0, c7, 0" : : "r" (0)); + isb(); } if (enable_monitor_mode()) -- 2.20.1