From: Felix Fietkau <n...@nbd.name>
many embedded boards have a disconnected TTL level serial which can
generate some garbage that can lead to spurious false sysrq detects.
Signed-off-by: John Crispin <j...@phrozen.org>
Signed-off-by: Felix Fietkau <n...@nbd.name>
---
include/linux/serial_core.h | 2 +-
lib/Kconfig.debug | 10 ++++++++++
2 files changed, 11 insertions(+), 1 deletion(-)
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 3442014..7e6165b 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -448,7 +448,7 @@ extern void uart_handle_cts_change(struct uart_port *uport,
extern void uart_insert_char(struct uart_port *port, unsigned int status,
unsigned int overrun, unsigned int ch, unsigned int flag);
-#ifdef SUPPORT_SYSRQ
+#if defined(SUPPORT_SYSRQ) && defined(CONFIG_MAGIC_SYSRQ_SERIAL)
static inline int
uart_handle_sysrq_char(struct uart_port *port, unsigned int ch)
{
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index a6c8db1..e370d0a 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -397,6 +397,16 @@ config MAGIC_SYSRQ_DEFAULT_ENABLE
This may be set to 1 or 0 to enable or disable them all, or
to a bitmask as described in Documentation/sysrq.txt.
+config MAGIC_SYSRQ_SERIAL
+ bool "Enable magic SysRq key over serial"
+ depends on MAGIC_SYSRQ
+ default y
+ help
+ Many embedded boards have a disconnected TTL level serial which can
+ generate some garbage that can lead to spurious false sysrq detects.
+ This option allows you to decide whether you want to enable the
+ magic SysRq key.
+
config DEBUG_KERNEL
bool "Kernel debugging"
help
--
1.7.10.4
