openwrt/target/linux/mvebu/patches-4.4/047-net-mvneta-Fix-spinlock-usage.patch
Koen Vandeputte 65044a50ab kernel: bump 4.4 to 4.4.167
Refreshed all patches.

Removed upstreamed:
- 203-MIPS-ath79-fix-restart.patch
- 330-Revert-MIPS-BCM47XX-Enable-74K-Core-ExternalSync-for.patch
- 051-0001-ovl-rename-is_merge-to-is_lowest.patch
- 051-0002-ovl-override-creds-with-the-ones-from-the-superblock.patch
- 051-0005-ovl-proper-cleanup-of-workdir.patch

Altered patches:
- 201-extra_optimization.patch
- 304-mips_disable_fpu.patch

Compile-tested on: ar71xx, cns3xxx, imx6, mpc85xx
Runtime-tested on: ar71xx, cns3xxx, imx6, mpc85xx

Signed-off-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
2018-12-18 15:14:39 +01:00

53 lines
1.9 KiB
Diff

From: Gregory CLEMENT <gregory.clement@free-electrons.com>
Date: Sat, 12 Mar 2016 18:44:17 +0100
Subject: [PATCH] net: mvneta: Fix spinlock usage
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 <patrick@puiterwijk.org>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
--- a/drivers/net/ethernet/marvell/mvneta.c
+++ b/drivers/net/ethernet/marvell/mvneta.c
@@ -3488,17 +3488,17 @@ 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);
@@ -4031,6 +4031,7 @@ 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;