From: Felix Fietkau <[email protected]> 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 <[email protected]> Signed-off-by: Felix Fietkau <[email protected]> --- 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
