bluetooth: scheduling while atomic bug fix

Due to driver core changes dev_set_drvdata will call kzalloc which should be
in might_sleep context, but hci_conn_add will be called in atomic context

Like dev_set_name move dev_set_drvdata to work queue function.

oops as following:

Oct  2 17:41:59 darkstar kernel: [  438.001341] BUG: sleeping function called from invalid context at mm/slqb.c:1546
Oct  2 17:41:59 darkstar kernel: [  438.001345] in_atomic(): 1, irqs_disabled(): 0, pid: 2133, name: sdptool
Oct  2 17:41:59 darkstar kernel: [  438.001348] 2 locks held by sdptool/2133:
Oct  2 17:41:59 darkstar kernel: [  438.001350]  #0:  (sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+.+.}, at: [<faa1d2f5>] lock_sock+0xa/0xc [l2cap]
Oct  2 17:41:59 darkstar kernel: [  438.001360]  #1:  (&hdev->lock){+.-.+.}, at: [<faa20e16>] l2cap_sock_connect+0x103/0x26b [l2cap]
Oct  2 17:41:59 darkstar kernel: [  438.001371] Pid: 2133, comm: sdptool Not tainted 2.6.31-mm1 #2
Oct  2 17:41:59 darkstar kernel: [  438.001373] Call Trace:
Oct  2 17:41:59 darkstar kernel: [  438.001381]  [<c022433f>] __might_sleep+0xde/0xe5
Oct  2 17:41:59 darkstar kernel: [  438.001386]  [<c0298843>] __kmalloc+0x4a/0x15a
Oct  2 17:41:59 darkstar kernel: [  438.001392]  [<c03f0065>] ? kzalloc+0xb/0xd
Oct  2 17:41:59 darkstar kernel: [  438.001396]  [<c03f0065>] kzalloc+0xb/0xd
Oct  2 17:41:59 darkstar kernel: [  438.001400]  [<c03f04ff>] device_private_init+0x15/0x3d
Oct  2 17:41:59 darkstar kernel: [  438.001405]  [<c03f24c5>] dev_set_drvdata+0x18/0x26
Oct  2 17:41:59 darkstar kernel: [  438.001414]  [<fa51fff7>] hci_conn_init_sysfs+0x40/0xd9 [bluetooth]
Oct  2 17:41:59 darkstar kernel: [  438.001422]  [<fa51cdc0>] ? hci_conn_add+0x128/0x186 [bluetooth]
Oct  2 17:41:59 darkstar kernel: [  438.001429]  [<fa51ce0f>] hci_conn_add+0x177/0x186 [bluetooth]
Oct  2 17:41:59 darkstar kernel: [  438.001437]  [<fa51cf8a>] hci_connect+0x3c/0xfb [bluetooth]
Oct  2 17:41:59 darkstar kernel: [  438.001442]  [<faa20e87>] l2cap_sock_connect+0x174/0x26b [l2cap]
Oct  2 17:41:59 darkstar kernel: [  438.001448]  [<c04c8df5>] sys_connect+0x60/0x7a
Oct  2 17:41:59 darkstar kernel: [  438.001453]  [<c024b703>] ? lock_release_non_nested+0x84/0x1de
Oct  2 17:41:59 darkstar kernel: [  438.001458]  [<c028804b>] ? might_fault+0x47/0x81
Oct  2 17:41:59 darkstar kernel: [  438.001462]  [<c028804b>] ? might_fault+0x47/0x81
Oct  2 17:41:59 darkstar kernel: [  438.001468]  [<c033361f>] ? __copy_from_user_ll+0x11/0xce
Oct  2 17:41:59 darkstar kernel: [  438.001472]  [<c04c9419>] sys_socketcall+0x82/0x17b
Oct  2 17:41:59 darkstar kernel: [  438.001477]  [<c020329d>] syscall_call+0x7/0xb
Signed-off-by: NDave Young <hidave.darkstar@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/bluetooth/hci_sysfs.c

@@ -92,6 +92,8 @@ static void add_conn(struct work_struct *work)
 
 	dev_set_name(&conn->dev, "%s:%d", hdev->name, conn->handle);
 
+	dev_set_drvdata(&conn->dev, conn);
+
 	if (device_add(&conn->dev) < 0) {
 		BT_ERR("Failed to register connection device");
 		return;
@@ -144,8 +146,6 @@ void hci_conn_init_sysfs(struct hci_conn *conn)
 	conn->dev.class = bt_class;
 	conn->dev.parent = &hdev->dev;
 
-	dev_set_drvdata(&conn->dev, conn);
-
 	device_initialize(&conn->dev);
 
 	INIT_WORK(&conn->work_add, add_conn);