From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:60048 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751611AbcDPQgP (ORCPT ); Sat, 16 Apr 2016 12:36:15 -0400 Subject: Patch "net: mvneta: Fix spinlock usage" has been added to the 4.5-stable tree To: gregory.clement@free-electrons.com, davem@davemloft.net, gregkh@linuxfoundation.org, patrick@puiterwijk.org Cc: , From: Date: Sat, 16 Apr 2016 09:35:25 -0700 Message-ID: <1460824525234194@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled net: mvneta: Fix spinlock usage to the 4.5-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-mvneta-fix-spinlock-usage.patch and it can be found in the queue-4.5 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From foo@baz Sat Apr 16 09:15:18 PDT 2016 From: Gregory CLEMENT Date: Sat, 12 Mar 2016 18:44:17 +0100 Subject: net: mvneta: Fix spinlock usage From: Gregory CLEMENT [ Upstream commit 1c2722a975fdb8c90bc6ba8570b7fb62db4e2e9c ] In the previous patch, the spinlock was not initialized. While it didn't cause any trouble yet it could be a problem to use it uninitialized. The most annoying part was the critical section protected by the spinlock in mvneta_stop(). Some of the functions could sleep as pointed when activated CONFIG_DEBUG_ATOMIC_SLEEP. Actually, in mvneta_stop() we only need to protect the is_stopped flagged, indeed the code of the notifier for CPU online is protected by the same spinlock, so when we get the lock, the notifer work is done. Reported-by: Patrick Uiterwijk Signed-off-by: Gregory CLEMENT Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/marvell/mvneta.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) --- a/drivers/net/ethernet/marvell/mvneta.c +++ b/drivers/net/ethernet/marvell/mvneta.c @@ -3070,17 +3070,17 @@ static int mvneta_stop(struct net_device struct mvneta_port *pp = netdev_priv(dev); /* Inform that we are stopping so we don't want to setup the - * driver for new CPUs in the notifiers + * driver for new CPUs in the notifiers. The code of the + * notifier for CPU online is protected by the same spinlock, + * so when we get the lock, the notifer work is done. */ spin_lock(&pp->lock); pp->is_stopped = true; + spin_unlock(&pp->lock); + mvneta_stop_dev(pp); mvneta_mdio_remove(pp); unregister_cpu_notifier(&pp->cpu_notifier); - /* Now that the notifier are unregistered, we can release le - * lock - */ - spin_unlock(&pp->lock); on_each_cpu(mvneta_percpu_disable, pp, true); free_percpu_irq(dev->irq, pp->ports); mvneta_cleanup_rxqs(pp); @@ -3612,6 +3612,7 @@ static int mvneta_probe(struct platform_ dev->ethtool_ops = &mvneta_eth_tool_ops; pp = netdev_priv(dev); + spin_lock_init(&pp->lock); pp->phy_node = phy_node; pp->phy_interface = phy_mode; Patches currently in stable-queue which might be from gregory.clement@free-electrons.com are queue-4.5/net-mvneta-fix-spinlock-usage.patch