1 files changed, 30 insertions, 0 deletions

diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index db01b95a47a5..c5d6bb4290ad 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -18,6 +18,7 @@
 #include <linux/device.h>
 #include <linux/module.h>
 #include <linux/kthread.h>
+#include <linux/wait.h>
 
 #include "base.h"
 #include "power/power.h"
@@ -70,6 +71,8 @@ struct stupid_thread_structure {
 };
 
 static atomic_t probe_count = ATOMIC_INIT(0);
+static DECLARE_WAIT_QUEUE_HEAD(probe_waitqueue);
+
 static int really_probe(void *void_data)
 {
         struct stupid_thread_structure *data = void_data;
@@ -121,6 +124,7 @@ probe_failed:
 done:
         kfree(data);
         atomic_dec(&probe_count);
+        wake_up(&probe_waitqueue);
         return ret;
 }
 
@@ -337,6 +341,32 @@ void driver_detach(struct device_driver * drv)
         }
 }
 
+#ifdef CONFIG_PCI_MULTITHREAD_PROBE
+static int __init wait_for_probes(void)
+{
+        DEFINE_WAIT(wait);
+
+        printk(KERN_INFO "%s: waiting for %d threads\n", __FUNCTION__,
+                        atomic_read(&probe_count));
+        if (!atomic_read(&probe_count))
+                return 0;
+        while (atomic_read(&probe_count)) {
+                prepare_to_wait(&probe_waitqueue, &wait, TASK_UNINTERRUPTIBLE);
+                if (atomic_read(&probe_count))
+                        schedule();
+        }
+        finish_wait(&probe_waitqueue, &wait);
+        return 0;
+}
+
+core_initcall_sync(wait_for_probes);
+postcore_initcall_sync(wait_for_probes);
+arch_initcall_sync(wait_for_probes);
+subsys_initcall_sync(wait_for_probes);
+fs_initcall_sync(wait_for_probes);
+device_initcall_sync(wait_for_probes);
+late_initcall_sync(wait_for_probes);
+#endif
 
 EXPORT_SYMBOL_GPL(device_bind_driver);
 EXPORT_SYMBOL_GPL(device_release_driver);