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| author | Felix Fietkau <nbd@nbd.name> | 2016-12-22 08:31:34 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-01-12 11:51:24 +0100 |
| commit | 732dbf3a6104a3abfcfcd066dcaf89e5054ce009 (patch) | |
| tree | 7bb0dec3e05e2f61365c005e34e536a7d74bfce4 | |
| parent | 552df698e9e88b580039ca715e1b5ad34b6e130b (diff) | |
| download | linux-732dbf3a6104a3abfcfcd066dcaf89e5054ce009.tar.gz linux-732dbf3a6104a3abfcfcd066dcaf89e5054ce009.tar.xz | |
serial: do not accept sysrq characters via serial port
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 <john@phrozen.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | include/linux/serial_core.h | 2 | ||||
| -rw-r--r-- | lib/Kconfig.debug | 10 |
2 files changed, 11 insertions, 1 deletions
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index 5def8e830fb0..58484fb35cc8 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -450,7 +450,7 @@ 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 b06848a104e6..9fa4e6eb1fe3 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -416,6 +416,16 @@ 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 |