Re: IEEE-1394 problem on init [ was Re: Linux 2.4.21-rc1 ]

[Stelian Pop <stelian.pop@fr.alcove.com>]

On Wed, Apr 23, 2003 at 05:29:40AM -0700, Tony Spinillo wrote:

> Stelian
> 
> Similiar problem here. Machine boots fine, but when I plug my DV
> camera in I can't cat /proc/bus/ieee1394/ devices, and I get looping
> messages in dmesg. If I move the 1394 drivers from pre-7 in, all works
> fine.
> (Thanks Dan). I submitted my logs and hw info to:
> http://sourceforge.net/mailarchive/forum.php?thread_id=2009188&forum_id=5387
> 

The following patch seems to cure my problem, I'm not sure yours
is the same.

I'm not absolutely sure about the corectness of the patch, but I
believe that kernel_thread should not be called with interrupts
disabled.

I'll leave up to the ieee1394 developpers to decide if some other,
semaphore based, locking is still necessary here.

Stelian.

===== drivers/ieee1394/nodemgr.c 1.19 vs edited =====
--- 1.19/drivers/ieee1394/nodemgr.c	Thu Apr 17 19:40:56 2003
+++ edited/drivers/ieee1394/nodemgr.c	Wed Apr 23 14:32:57 2003
@@ -1417,8 +1417,6 @@
 	init_completion(&hi->exited);
         sema_init(&hi->reset_sem, 0);
 
-	spin_lock_irqsave (&host_info_lock, flags);
-
 	hi->pid = kernel_thread(nodemgr_host_thread, hi,
 				CLONE_FS | CLONE_FILES | CLONE_SIGHAND);
 	
@@ -1426,9 +1424,10 @@
 		HPSB_ERR ("NodeMgr: failed to start NodeMgr thread for %s",
 			  host->driver->name);
 		kfree(hi);
-		spin_unlock_irqrestore (&host_info_lock, flags);
 		return;
 	}
+
+	spin_lock_irqsave (&host_info_lock, flags);
 
 	list_add_tail(&hi->list, &host_info_list);
 
-- 
Stelian Pop <stelian.pop@fr.alcove.com>
Alcove - http://www.alcove.com