[ 35/47] pktgen: fix module unload for good

Greg KH
2012-06-07T04:29:12Z

From: Eric Dumazet <edumazet@google.com>

[ Upstream commit d4b1133558e0d417342d5d2c49e4c35b428ff20d ]

commit c57b5468406 (pktgen: fix crash at module unload) did a very poor
job with list primitives.

1) list_splice() arguments were in the wrong order

2) list_splice(list, head) has undefined behavior if head is not
initialized.

3) We should use the list_splice_init() variant to clear pktgen_threads
list.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/core/pktgen.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -3755,13 +3755,13 @@ static void __exit pg_cleanup(void)
{
struct pktgen_thread *t;
struct list_head *q, *n;
- struct list_head list;
+ LIST_HEAD(list);

/* Stop all interfaces & threads */
pktgen_exiting = true;

mutex_lock(&pktgen_thread_lock);
- list_splice(&list, &pktgen_threads);
+ list_splice_init(&pktgen_threads, &list);
mutex_unlock(&pktgen_thread_lock);

list_for_each_safe(q, n, &list) {