netdev - [PATCH] team: set qdisc_tx_busylock to avoid LOCKDEP splat

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <1349342319.16011.30.camel@edumazet-glaptop>
Date:	Thu, 04 Oct 2012 11:18:39 +0200
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	David Miller <davem@...emloft.net>
Cc:	netdev <netdev@...r.kernel.org>, Jiri Pirko <jpirko@...hat.com>
Subject: [PATCH] team: set qdisc_tx_busylock to avoid LOCKDEP splat

From: Eric Dumazet <edumazet@...gle.com>

If a qdisc is installed on a team device, its possible to get
a lockdep splat under stress, because nested dev_queue_xmit() can
lock busylock a second time (on a different device, so its a false
positive)

Avoid this problem using a distinct lock_class_key for team
devices.

Signed-off-by: Eric Dumazet <edumazet@...gle.com>
Cc: Jiri Pirko <jpirko@...hat.com>
---
 drivers/net/team/team.c |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c
index 5c7547c..d44cca3 100644
--- a/drivers/net/team/team.c
+++ b/drivers/net/team/team.c
@@ -1315,6 +1315,7 @@ static const struct team_option team_options[] = {
 
 static struct lock_class_key team_netdev_xmit_lock_key;
 static struct lock_class_key team_netdev_addr_lock_key;
+static struct lock_class_key team_tx_busylock_key;
 
 static void team_set_lockdep_class_one(struct net_device *dev,
 				       struct netdev_queue *txq,
@@ -1327,6 +1328,7 @@ static void team_set_lockdep_class(struct net_device *dev)
 {
 	lockdep_set_class(&dev->addr_list_lock, &team_netdev_addr_lock_key);
 	netdev_for_each_tx_queue(dev, team_set_lockdep_class_one, NULL);
+	dev->qdisc_tx_busylock = &team_tx_busylock_key;
 }
 
 static int team_init(struct net_device *dev)


--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html