3.16.58-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: "Shuah Khan (Samsung OSG)" <shuah@xxxxxxxxxx>
commit 7510df3f29d44685bab7b1918b61a8ccd57126a9 upstream.
After removing usbip_host module, devices it releases are left without
a driver. For example, when a keyboard or a mass storage device are
bound to usbip_host when it is removed, these devices are no longer
bound to any driver.
Fix it to run device_attach() from the module exit routine to restore
the devices to their original drivers. This includes cleanup changes
and moving device_attach() code to a common routine to be called from
rebind_store() and usbip_host_exit().
Signed-off-by: Shuah Khan (Samsung OSG) <shuah@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
[bwh: Backported to 3.16: adjust filenames]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/staging/usbip/stub_dev.c | 6 +---
drivers/staging/usbip/stub_main.c | 60 +++++++++++++++++++++++++++++------
2 files changed, 52 insertions(+), 14 deletions(-)
--- a/drivers/staging/usbip/stub_dev.c
+++ b/drivers/staging/usbip/stub_dev.c
@@ -490,12 +490,8 @@ static void stub_disconnect(struct usb_d
busid_priv->sdev = NULL;
stub_device_free(sdev);
- if (busid_priv->status == STUB_BUSID_ALLOC) {
+ if (busid_priv->status == STUB_BUSID_ALLOC)
busid_priv->status = STUB_BUSID_ADDED;
- } else {
- busid_priv->status = STUB_BUSID_OTHER;
- del_match_busid((char *)udev_busid);
- }
}
#ifdef CONFIG_PM
--- a/drivers/staging/usbip/stub_main.c
+++ b/drivers/staging/usbip/stub_main.c
@@ -28,6 +28,7 @@
#define DRIVER_DESC "USB/IP Host Driver"
struct kmem_cache *stub_priv_cache;
+
/*
* busid_tables defines matching busids that usbip can grab. A user can change
* dynamically what device is locally used and what device is exported to a
@@ -188,6 +189,51 @@ static ssize_t store_match_busid(struct
static DRIVER_ATTR(match_busid, S_IRUSR | S_IWUSR, show_match_busid,
store_match_busid);
+static int do_rebind(char *busid, struct bus_id_priv *busid_priv)
+{
+ int ret;
+
+ /* device_attach() callers should hold parent lock for USB */
+ if (busid_priv->udev->dev.parent)
+ device_lock(busid_priv->udev->dev.parent);
+ ret = device_attach(&busid_priv->udev->dev);
+ if (busid_priv->udev->dev.parent)
+ device_unlock(busid_priv->udev->dev.parent);
+ if (ret < 0) {
+ dev_err(&busid_priv->udev->dev, "rebind failed\n");
+ return ret;
+ }
+ return 0;
+}
+
+static void stub_device_rebind(void)
+{
+#if IS_MODULE(CONFIG_USBIP_HOST)
+ struct bus_id_priv *busid_priv;
+ int i;
+
+ /* update status to STUB_BUSID_OTHER so probe ignores the device */
+ spin_lock(&busid_table_lock);
+ for (i = 0; i < MAX_BUSID; i++) {
+ if (busid_table[i].name[0] &&
+ busid_table[i].shutdown_busid) {
+ busid_priv = &(busid_table[i]);
+ busid_priv->status = STUB_BUSID_OTHER;
+ }
+ }
+ spin_unlock(&busid_table_lock);
+
+ /* now run rebind */
+ for (i = 0; i < MAX_BUSID; i++) {
+ if (busid_table[i].name[0] &&
+ busid_table[i].shutdown_busid) {
+ busid_priv = &(busid_table[i]);
+ do_rebind(busid_table[i].name, busid_priv);
+ }
+ }
+#endif
+}
+
static ssize_t rebind_store(struct device_driver *dev, const char *buf,
size_t count)
{
@@ -208,16 +254,9 @@ static ssize_t rebind_store(struct devic
/* mark the device for deletion so probe ignores it during rescan */
bid->status = STUB_BUSID_OTHER;
- /* device_attach() callers should hold parent lock for USB */
- if (bid->udev->dev.parent)
- device_lock(bid->udev->dev.parent);
- ret = device_attach(&bid->udev->dev);
- if (bid->udev->dev.parent)
- device_unlock(bid->udev->dev.parent);
- if (ret < 0) {
- dev_err(&bid->udev->dev, "rebind failed\n");
+ ret = do_rebind((char *) buf, bid);
+ if (ret < 0)
return ret;
- }
/* delete device from busid_table */
del_match_busid((char *) buf);
@@ -343,6 +382,9 @@ static void __exit usbip_host_exit(void)
*/
usb_deregister_device_driver(&stub_driver);
+ /* initiate scan to attach devices */
+ stub_device_rebind();
+
kmem_cache_destroy(stub_priv_cache);
}
