return 0;
}
+#ifdef CONFIG_KGDB_KDB
+void kdb_dump_stack_on_cpu(int cpu)
+{
+ if (cpu == raw_smp_processor_id() || !IS_ENABLED(CONFIG_SMP)) {
+ dump_stack();
+ return;
+ }
+
+ if (!(kgdb_info[cpu].exception_state & DCPU_IS_SLAVE)) {
+ kdb_printf("ERROR: Task on cpu %d didn't stop in the debugger\n",
+ cpu);
+ return;
+ }
+
+ /*
+ * In general, architectures don't support dumping the stack of a
+ * "running" process that's not the current one. From the point of
+ * view of the Linux, kernel processes that are looping in the kgdb
+ * slave loop are still "running". There's also no API (that actually
+ * works across all architectures) that can do a stack crawl based
+ * on registers passed as a parameter.
+ *
+ * Solve this conundrum by asking slave CPUs to do the backtrace
+ * themselves.
+ */
+ kgdb_info[cpu].exception_state |= DCPU_WANT_BT;
+ while (kgdb_info[cpu].exception_state & DCPU_WANT_BT)
+ cpu_relax();
+}
+#endif
+
/*
* Return true if there is a valid kgdb I/O module. Also if no
* debugger is attached a message can be printed to the console about
atomic_xchg(&kgdb_active, cpu);
break;
}
+ } else if (kgdb_info[cpu].exception_state & DCPU_WANT_BT) {
+ dump_stack();
+ kgdb_info[cpu].exception_state &= ~DCPU_WANT_BT;
} else if (kgdb_info[cpu].exception_state & DCPU_IS_SLAVE) {
if (!raw_spin_is_locked(&dbg_slave_lock))
goto return_normal;