[PATCH 03/11] kdb: Implement disable_nmi command
From: Anton Vorontsov <hidden>
Date: 2012-07-30 12:03:47
Also in:
lkml
Subsystem:
kgdb / kdb /debug_core, the rest · Maintainers:
Jason Wessel, Daniel Thompson, Linus Torvalds
This command disables NMI-entry. If NMI source was previously shared with
a serial console ("debug port"), this effectively releases the port from
KDB exclusive use, and makes the console available for normal use.
Of course, NMI can be reenabled, enable_nmi modparam is used for that:
echo 1 > /sys/module/kdb/parameters/enable_nmi
Signed-off-by: Anton Vorontsov <redacted>
---
kernel/debug/kdb/kdb_main.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index 3ee92a1..1e9f20e 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c@@ -2131,6 +2131,24 @@ static int kdb_dmesg(int argc, const char **argv) return 0; } #endif /* CONFIG_PRINTK */ + +static int kdb_disable_nmi(int argc, const char *argv[]) +{ + kgdb_arch_enable_nmi(0); + return 0; +} + +static int kdb_param_enable_nmi(const char *val, const struct kernel_param *kp) +{ + kgdb_arch_enable_nmi(1); + return 0; +} + +static const struct kernel_param_ops kdb_param_ops_enable_nmi = { + .set = kdb_param_enable_nmi, +}; +module_param_cb(enable_nmi, &kdb_param_ops_enable_nmi, NULL, 0600); + /* * kdb_cpu - This function implements the 'cpu' command. * cpu [<cpunum>]
@@ -2873,6 +2891,8 @@ static void __init kdb_inittab(void) kdb_register_flags("dmesg", kdb_dmesg, "[lines]", "Display syslog buffer", 0, KDB_SAFE); #endif + kdb_register_flags("disable_nmi", kdb_disable_nmi, "", + "Disable NMI entry to KDB", 0, KDB_SAFE); kdb_register_flags("defcmd", kdb_defcmd, "name \"usage\" \"help\"", "Define a set of commands, down to endefcmd", 0, KDB_SAFE); kdb_register_flags("kill", kdb_kill, "<-signal> <pid>",
--
1.7.10.4