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-rw-r--r--include/linux/kgdb.h1
-rw-r--r--kernel/debug/debug_core.c26
2 files changed, 27 insertions, 0 deletions
diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h
index 19d1b29a2694..ee007ea341b8 100644
--- a/include/linux/kgdb.h
+++ b/include/linux/kgdb.h
@@ -271,6 +271,7 @@ extern int kgdb_mem2hex(char *mem, char *buf, int count);
extern int kgdb_hex2mem(char *buf, char *mem, int count);
extern int kgdb_isremovedbreak(unsigned long addr);
+extern void kgdb_schedule_breakpoint(void);
extern int
kgdb_handle_exception(int ex_vector, int signo, int err_code,
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index 375e42f0baf0..fff59019cca0 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -114,6 +114,7 @@ EXPORT_SYMBOL_GPL(kgdb_active);
*/
static atomic_t passive_cpu_wait[NR_CPUS];
static atomic_t cpu_in_kgdb[NR_CPUS];
+static atomic_t kgdb_break_tasklet_var;
atomic_t kgdb_setting_breakpoint;
struct task_struct *kgdb_usethread;
@@ -789,6 +790,31 @@ static void kgdb_unregister_callbacks(void)
}
}
+/*
+ * There are times a tasklet needs to be used vs a compiled in
+ * break point so as to cause an exception outside a kgdb I/O module,
+ * such as is the case with kgdboe, where calling a breakpoint in the
+ * I/O driver itself would be fatal.
+ */
+static void kgdb_tasklet_bpt(unsigned long ing)
+{
+ kgdb_breakpoint();
+ atomic_set(&kgdb_break_tasklet_var, 0);
+}
+
+static DECLARE_TASKLET(kgdb_tasklet_breakpoint, kgdb_tasklet_bpt, 0);
+
+void kgdb_schedule_breakpoint(void)
+{
+ if (atomic_read(&kgdb_break_tasklet_var) ||
+ atomic_read(&kgdb_active) != -1 ||
+ atomic_read(&kgdb_setting_breakpoint))
+ return;
+ atomic_inc(&kgdb_break_tasklet_var);
+ tasklet_schedule(&kgdb_tasklet_breakpoint);
+}
+EXPORT_SYMBOL_GPL(kgdb_schedule_breakpoint);
+
static void kgdb_initial_breakpoint(void)
{
kgdb_break_asap = 0;
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