Without treating events with timeouts specially some drivers would
cause a 30 seconds stall on boot: .

I also received reports of some drivers not working at all, even
after the timeout.

We will remove this patch when more drivers have been fixed in
the kernel (3.4?).

This reverts 43d5c5f03645c4b842659f9b5bd0ae465e885e92 and
57c6f8ae5f52a6e8ffc66a54966346f733dded39.
---

Note: this is mostly a FYI, and whether or not it makes sense
to apply this upstream depends on how big problems other report
regarding this issue.

 src/libudev-device.c  |   19 +++++++++++++++++++
 src/libudev-private.h |    1 +
 src/udevd.c           |   13 ++++++++++---
 4 files changed, 32 insertions(+), 3 deletions(-)

Index: systemd-195/src/libudev/libudev-device.c
===================================================================
--- systemd-195.orig/src/libudev/libudev-device.c
+++ systemd-195/src/libudev/libudev-device.c
@@ -68,6 +68,7 @@ struct udev_device {
         struct udev_list tags_list;
         unsigned long long int seqnum;
         unsigned long long int usec_initialized;
+        int timeout;
         int devlink_priority;
         int refcount;
         dev_t devnum;
@@ -162,6 +163,21 @@ static int udev_device_set_devnum(struct
         return 0;
 }
 
+int udev_device_get_timeout(struct udev_device *udev_device)
+{
+        return udev_device->timeout;
+}
+
+static int udev_device_set_timeout(struct udev_device *udev_device, int timeout)
+{
+        char num[32];
+
+        udev_device->timeout = timeout;
+        snprintf(num, sizeof(num), "%u", timeout);
+        udev_device_add_property(udev_device, "TIMEOUT", num);
+        return 0;
+}
+
 const char *udev_device_get_devpath_old(struct udev_device *udev_device)
 {
         return udev_device->devpath_old;
@@ -418,6 +434,8 @@ void udev_device_add_property_from_strin
                 udev_device_set_devpath_old(udev_device, &property[12]);
         } else if (startswith(property, "SEQNUM=")) {
                 udev_device_set_seqnum(udev_device, strtoull(&property[7], NULL, 10));
+        } else if (startswith(property, "TIMEOUT=")) {
+                udev_device_set_timeout(udev_device, strtoull(&property[8], NULL, 10));
         } else if (startswith(property, "IFINDEX=")) {
                 udev_device_set_ifindex(udev_device, strtoull(&property[8], NULL, 10));
         } else if (startswith(property, "DEVMODE=")) {
@@ -605,6 +623,7 @@ struct udev_device *udev_device_new(stru
         udev_list_init(udev, &udev_device->sysattr_value_list, true);
         udev_list_init(udev, &udev_device->sysattr_list, false);
         udev_list_init(udev, &udev_device->tags_list, true);
+        udev_device->timeout = -1;
         udev_device->watch_handle = -1;
         /* copy global properties */
         udev_list_entry_foreach(list_entry, udev_get_properties_list_entry(udev))
Index: systemd-195/src/libudev/libudev-private.h
===================================================================
--- systemd-195.orig/src/libudev/libudev-private.h
+++ systemd-195/src/libudev/libudev-private.h
@@ -65,6 +65,7 @@ const char *udev_device_get_id_filename(
 void udev_device_set_is_initialized(struct udev_device *udev_device);
 int udev_device_add_tag(struct udev_device *udev_device, const char *tag);
 void udev_device_cleanup_tags_list(struct udev_device *udev_device);
+int udev_device_get_timeout(struct udev_device *udev_device);
 unsigned long long udev_device_get_usec_initialized(struct udev_device *udev_device);
 void udev_device_set_usec_initialized(struct udev_device *udev_device, unsigned long long usec_initialized);
 int udev_device_get_devlink_priority(struct udev_device *udev_device);
Index: systemd-195/src/udev/udevd.c
===================================================================
--- systemd-195.orig/src/udev/udevd.c
+++ systemd-195/src/udev/udevd.c
@@ -388,7 +388,7 @@ out:
         }
 }
 
-static void event_run(struct event *event)
+static void event_run(struct event *event, bool force)
 {
         struct udev_list_node *loop;
 
@@ -414,7 +414,7 @@ static void event_run(struct event *even
                 return;
         }
 
-        if (children >= children_max) {
+        if (!force && children >= children_max) {
                 if (children_max > 1)
                         log_debug("maximum number (%i) of children reached\n", children);
                 return;
@@ -450,6 +450,13 @@ static int event_queue_insert(struct ude
 
         event->state = EVENT_QUEUED;
         udev_list_node_append(&event->node, &event_list);
+
+        /* run all events with a timeout set immediately */
+        if (udev_device_get_timeout(dev) > 0) {
+                event_run(event, true);
+                return 0;
+        }
+
         return 0;
 }
 
@@ -559,7 +566,7 @@ static void event_queue_start(struct ude
                 if (is_devpath_busy(event))
                         continue;
 
-                event_run(event);
+                event_run(event, false);
         }
 }