| From fb00986d4aeeacc15e60ff5bea4761549281de98 Mon Sep 17 00:00:00 2001 |
| From: Eric Dumazet <edumazet@google.com> |
| Date: Mon, 13 May 2013 02:24:11 +0000 |
| Subject: net/802/mrp: fix lockdep splat |
| |
| From: Eric Dumazet <edumazet@google.com> |
| |
| [ Upstream commit faff57a92ba1d7247c5e86ecea2886d2c9d54507 ] |
| |
| commit fb745e9a037895 ("net/802/mrp: fix possible race condition when |
| calling mrp_pdu_queue()") introduced a lockdep splat. |
| |
| [ 19.735147] ================================= |
| [ 19.735235] [ INFO: inconsistent lock state ] |
| [ 19.735324] 3.9.2-build-0063 #4 Not tainted |
| [ 19.735412] --------------------------------- |
| [ 19.735500] inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage. |
| [ 19.735592] rmmod/1840 [HC0[0]:SC0[0]:HE1:SE1] takes: |
| [ 19.735682] (&(&app->lock)->rlock#2){+.?...}, at: [<f862bb5b>] |
| mrp_uninit_applicant+0x69/0xba [mrp] |
| |
| app->lock is normally taken under softirq context, so disable BH to |
| avoid the splat. |
| |
| Reported-by: Denys Fedoryshchenko <denys@visp.net.lb> |
| Signed-off-by: Eric Dumazet <edumazet@google.com> |
| Cc: David Ward <david.ward@ll.mit.edu> |
| Cc: Cong Wang <amwang@redhat.com> |
| Tested-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/802/mrp.c | 4 ++-- |
| 1 file changed, 2 insertions(+), 2 deletions(-) |
| |
| --- a/net/802/mrp.c |
| +++ b/net/802/mrp.c |
| @@ -871,10 +871,10 @@ void mrp_uninit_applicant(struct net_dev |
| */ |
| del_timer_sync(&app->join_timer); |
| |
| - spin_lock(&app->lock); |
| + spin_lock_bh(&app->lock); |
| mrp_mad_event(app, MRP_EVENT_TX); |
| mrp_pdu_queue(app); |
| - spin_unlock(&app->lock); |
| + spin_unlock_bh(&app->lock); |
| |
| mrp_queue_xmit(app); |
| |