[PATCH] raw1394 : Fix hang on unload

[Parag Warudkar <kernel-stuff@comcast.net>]

[-- Attachment #1: Type: text/plain, Size: 1079 bytes --]

I was seeing rmmod getting stuck consistently in D state while removing
raw1394. Looking at raw1394.c:cleanup_raw1394 - the order of doing
things seemed incorrect to me after comparing other places in raw1394.c
which do the same thing but with a different order.

bash          R  running task       0  4319   3884                3900
(NOTLB)
rmmod         D 0000008428792a16     0  4490   3900
(NOTLB)
ffff81001cff9dd8 0000000000000082 0000000000000000 0000000100000000
       0000007400000000 ffff8100211c9070 000000000000097b
ffff81002c8a2800
       ffffffff80397c97 ffff81002b6f9360
Call Trace:<ffffffff80379d25>{__down+421}
<ffffffff80133510>{default_wake_function+0}
       <ffffffff8037cd8c>{__down_failed+53}
<ffffffff801c0e40>{generic_delete_inode+0}
       <ffffffff8029e540>{.text.lock.driver+5}
<ffffffff885a8260>{:raw1394:cleanup_raw1394+16}
       <ffffffff8015eb31>{sys_delete_module+497}
<ffffffff8021a692>{__up_write+514}
       <ffffffff80183efb>{sys_munmap+107} <ffffffff8010ecda>{system_call
+126}

Attached patch fixes the rmmod raw1394 hang. Tested.

Parag

[-- Attachment #2: raw1394.c.patch --]
[-- Type: text/x-patch, Size: 460 bytes --]

--- drivers/ieee1394/raw1394.c.orig	2005-02-06 14:34:58.000000000 -0500
+++ drivers/ieee1394/raw1394.c	2005-02-06 14:36:18.000000000 -0500
@@ -2758,10 +2758,10 @@
 
 static void __exit cleanup_raw1394(void)
 {
-	hpsb_unregister_protocol(&raw1394_driver);
 	cdev_del(&raw1394_cdev);
         devfs_remove(RAW1394_DEVICE_NAME);
         hpsb_unregister_highlevel(&raw1394_highlevel);
+	hpsb_unregister_protocol(&raw1394_driver);
 }
 
 module_init(init_raw1394);