From c421122f3dea5b5c42133f67a8084e6c0793a35c Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Tue, 5 Apr 2011 13:57:53 +0100 Subject: ARM: 6864/1: hw_breakpoint: clear DBGVCR out of reset commit e89c0d7090c54d7b11b9b091e495a1ae345dd3ff upstream. 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. Reported-by: Stepan Moskovchenko Signed-off-by: Will Deacon Signed-off-by: Russell King Signed-off-by: Greg Kroah-Hartman --- arch/arm/kernel/hw_breakpoint.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'arch') diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c index 44b84fe6e1b..7e9a0c7f198 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()) -- cgit v1.2.3