[PATCH 1/1]x25: fix for spinlock recurse and spinlock lockup with timer handler in x25

[PATCH 1/1]x25: fix for spinlock recurse and spinlock lockup with timer handler in x25

[Shaun Pereira]

From: spereira@tusc.com.au

When the sk_timer function x25_heartbeat_expiry() is called by the kernel
in a running/terminating process, spinlock-recursion and spinlock-lockup
locks up the kernel. 
This has happened with testing on some distro's and the patch below fixed it.

Signed-off-by:Shaun Pereira <spereira@tusc.com.au>

diff -uprN -X dontdiff linux-2.6.17-rc2-vanilla/net/x25/x25_timer.c linux-2.6.17-rc2/net/x25/x25_timer.c
--- linux-2.6.17-rc2-vanilla/net/x25/x25_timer.c	2006-04-20 12:00:03.000000000 +1000
+++ linux-2.6.17-rc2/net/x25/x25_timer.c	2006-04-20 12:02:43.000000000 +1000
@@ -114,8 +114,9 @@ static void x25_heartbeat_expiry(unsigne
 			if (sock_flag(sk, SOCK_DESTROY) ||
 			    (sk->sk_state == TCP_LISTEN &&
 			     sock_flag(sk, SOCK_DEAD))) {
+				bh_unlock_sock(sk);
 				x25_destroy_socket(sk);
-				goto unlock;
+				return;
 			}
 			break;
 
@@ -128,7 +129,6 @@ static void x25_heartbeat_expiry(unsigne
 	}
 restart_heartbeat:
 	x25_start_heartbeat(sk);
-unlock:
 	bh_unlock_sock(sk);
 }
 

Re: [PATCH 1/1]x25: fix for spinlock recurse and spinlock lockup with timer handler in x25

[David S. Miller]

From: Shaun Pereira <spereira@tusc.com.au>
Date: Thu, 20 Apr 2006 15:03:23 +1000

> From: spereira@tusc.com.au
> 
> When the sk_timer function x25_heartbeat_expiry() is called by the kernel
> in a running/terminating process, spinlock-recursion and spinlock-lockup
> locks up the kernel. 
> This has happened with testing on some distro's and the patch below fixed it.
> 
> Signed-off-by:Shaun Pereira <spereira@tusc.com.au>

Applied, thanks.