From f52ce59f4c6fe1dbae1d2d84f9e6e7784f6658db Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Tue, 19 Nov 2013 00:09:21 +0000 Subject: [PATCH] kernel: do not accept sysrq characters via serial port many boards have a disconnected TTL level serial which can generate some garbage that can lead to spurious false sysrq detects. Signed-off-by: Felix Fietkau Backport of r37210 SVN-Revision: 38863 --- target/linux/generic/config-3.3 | 1 + .../patches-3.3/890-8250_optional_sysrq.patch | 24 +++++++++++++++++++ 2 files changed, 25 insertions(+) create mode 100644 target/linux/generic/patches-3.3/890-8250_optional_sysrq.patch diff --git a/target/linux/generic/config-3.3 b/target/linux/generic/config-3.3 index 4f18587ca9..8f2f437bc0 100644 --- a/target/linux/generic/config-3.3 +++ b/target/linux/generic/config-3.3 @@ -2576,6 +2576,7 @@ CONFIG_SERIAL_8250_CONSOLE=y CONFIG_SERIAL_8250_NR_UARTS=2 # CONFIG_SERIAL_8250_PCI is not set CONFIG_SERIAL_8250_RUNTIME_UARTS=2 +# CONFIG_SERIAL_8250_SYSRQ is not set # CONFIG_SERIAL_ALTERA_JTAGUART is not set # CONFIG_SERIAL_ALTERA_UART is not set CONFIG_SERIAL_CORE=y diff --git a/target/linux/generic/patches-3.3/890-8250_optional_sysrq.patch b/target/linux/generic/patches-3.3/890-8250_optional_sysrq.patch new file mode 100644 index 0000000000..414e18e825 --- /dev/null +++ b/target/linux/generic/patches-3.3/890-8250_optional_sysrq.patch @@ -0,0 +1,24 @@ +--- a/drivers/tty/serial/8250/8250.c ++++ b/drivers/tty/serial/8250/8250.c +@@ -16,7 +16,7 @@ + * membase is an 'ioremapped' cookie. + */ + +-#if defined(CONFIG_SERIAL_8250_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) ++#if defined(CONFIG_SERIAL_8250_SYSRQ) && defined(CONFIG_MAGIC_SYSRQ) + #define SUPPORT_SYSRQ + #endif + +--- a/drivers/tty/serial/8250/Kconfig ++++ b/drivers/tty/serial/8250/Kconfig +@@ -66,6 +66,10 @@ config SERIAL_8250_CONSOLE + + If unsure, say N. + ++config SERIAL_8250_SYSRQ ++ bool "Magic sysrq support on 8250/16550 devices" ++ depends on SERIAL_8250_CONSOLE ++ + config FIX_EARLYCON_MEM + bool + depends on X86 -- 2.30.2