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Diffstat (limited to 'kernel/debug')
-rw-r--r--kernel/debug/debug_core.c14
-rw-r--r--kernel/debug/kdb/kdb_main.c31
2 files changed, 42 insertions, 3 deletions
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index 8bfa373cd5fd..9a61738cefc8 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -672,6 +672,10 @@ kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs)
{
struct kgdb_state kgdb_var;
struct kgdb_state *ks = &kgdb_var;
+ int ret = 0;
+
+ if (arch_kgdb_ops.enable_nmi)
+ arch_kgdb_ops.enable_nmi(0);
ks->cpu = raw_smp_processor_id();
ks->ex_vector = evector;
@@ -681,11 +685,15 @@ kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs)
ks->linux_regs = regs;
if (kgdb_reenter_check(ks))
- return 0; /* Ouch, double exception ! */
+ goto out; /* Ouch, double exception ! */
if (kgdb_info[ks->cpu].enter_kgdb != 0)
- return 0;
+ goto out;
- return kgdb_cpu_enter(ks, regs, DCPU_WANT_MASTER);
+ ret = kgdb_cpu_enter(ks, regs, DCPU_WANT_MASTER);
+out:
+ if (arch_kgdb_ops.enable_nmi)
+ arch_kgdb_ops.enable_nmi(1);
+ return ret;
}
/*
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index 1afeb5c1e5a9..4d5f8d5612f3 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -21,6 +21,7 @@
#include <linux/smp.h>
#include <linux/utsname.h>
#include <linux/vmalloc.h>
+#include <linux/atomic.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/init.h>
@@ -2109,6 +2110,32 @@ static int kdb_dmesg(int argc, const char **argv)
return 0;
}
#endif /* CONFIG_PRINTK */
+
+/* Make sure we balance enable/disable calls, must disable first. */
+static atomic_t kdb_nmi_disabled;
+
+static int kdb_disable_nmi(int argc, const char *argv[])
+{
+ if (atomic_read(&kdb_nmi_disabled))
+ return 0;
+ atomic_set(&kdb_nmi_disabled, 1);
+ arch_kgdb_ops.enable_nmi(0);
+ return 0;
+}
+
+static int kdb_param_enable_nmi(const char *val, const struct kernel_param *kp)
+{
+ if (!atomic_add_unless(&kdb_nmi_disabled, -1, 0))
+ return -EINVAL;
+ arch_kgdb_ops.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>]
@@ -2853,6 +2880,10 @@ static void __init kdb_inittab(void)
kdb_register_repeat("dmesg", kdb_dmesg, "[lines]",
"Display syslog buffer", 0, KDB_REPEAT_NONE);
#endif
+ if (arch_kgdb_ops.enable_nmi) {
+ kdb_register_repeat("disable_nmi", kdb_disable_nmi, "",
+ "Disable NMI entry to KDB", 0, KDB_REPEAT_NONE);
+ }
kdb_register_repeat("defcmd", kdb_defcmd, "name \"usage\" \"help\"",
"Define a set of commands, down to endefcmd", 0, KDB_REPEAT_NONE);
kdb_register_repeat("kill", kdb_kill, "<-signal> <pid>",