From: Jean-Philippe Brucker <jean-philippe.brucker@xxxxxxx>
Some firmwares may reboot CPUs with OS Double Lock set. Make sure that
it is unlocked, in order to use debug exceptions.
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@xxxxxxx>
Signed-off-by: Will Deacon <will.deacon@xxxxxxx>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
---
arch/arm64/kernel/debug-monitors.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c
index 800486cc48239..555b6bd2f3d68 100644
--- a/arch/arm64/kernel/debug-monitors.c
+++ b/arch/arm64/kernel/debug-monitors.c
@@ -135,6 +135,7 @@ NOKPROBE_SYMBOL(disable_debug_monitors);
*/
static int clear_os_lock(unsigned int cpu)
{
+ write_sysreg(0, osdlr_el1);
write_sysreg(0, oslar_el1);
isb();
return 0;
--
2.19.1
