diff options
Diffstat (limited to 'drivers/net/netconsole.c')
| -rw-r--r-- | drivers/net/netconsole.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/drivers/net/netconsole.c b/drivers/net/netconsole.c index 4822aafe638..c9a15925a1f 100644 --- a/drivers/net/netconsole.c +++ b/drivers/net/netconsole.c @@ -102,6 +102,7 @@ struct netconsole_target { struct config_item item; #endif int enabled; + struct mutex mutex; struct netpoll np; }; @@ -181,6 +182,7 @@ static struct netconsole_target *alloc_param_target(char *target_config) strlcpy(nt->np.dev_name, "eth0", IFNAMSIZ); nt->np.local_port = 6665; nt->np.remote_port = 6666; + mutex_init(&nt->mutex); memset(nt->np.remote_mac, 0xff, ETH_ALEN); /* Parse parameters and setup netpoll */ @@ -308,6 +310,7 @@ static ssize_t store_enabled(struct netconsole_target *nt, const char *buf, size_t count) { + unsigned long flags; int enabled; int err; @@ -323,7 +326,6 @@ static ssize_t store_enabled(struct netconsole_target *nt, } if (enabled) { /* 1 */ - /* * Skip netpoll_parse_options() -- all the attributes are * already configured via configfs. Just print them out. @@ -335,8 +337,14 @@ static ssize_t store_enabled(struct netconsole_target *nt, return err; printk(KERN_INFO "netconsole: network logging started\n"); - } else { /* 0 */ + /* We need to disable the netconsole before cleaning it up + * otherwise we might end up in write_msg() with + * nt->np.dev == NULL and nt->enabled == 1 + */ + spin_lock_irqsave(&target_list_lock, flags); + nt->enabled = 0; + spin_unlock_irqrestore(&target_list_lock, flags); netpoll_cleanup(&nt->np); } @@ -557,8 +565,10 @@ static ssize_t netconsole_target_attr_store(struct config_item *item, struct netconsole_target_attr *na = container_of(attr, struct netconsole_target_attr, attr); + mutex_lock(&nt->mutex); if (na->store) ret = na->store(nt, buf, count); + mutex_unlock(&nt->mutex); return ret; } @@ -597,6 +607,7 @@ static struct config_item *make_netconsole_target(struct config_group *group, strlcpy(nt->np.dev_name, "eth0", IFNAMSIZ); nt->np.local_port = 6665; nt->np.remote_port = 6666; + mutex_init(&nt->mutex); memset(nt->np.remote_mac, 0xff, ETH_ALEN); /* Initialize the config_item member */ @@ -677,12 +688,13 @@ restart: case NETDEV_RELEASE: case NETDEV_JOIN: case NETDEV_UNREGISTER: - /* - * rtnl_lock already held + /* rtnl_lock already held * we might sleep in __netpoll_cleanup() */ spin_unlock_irqrestore(&target_list_lock, flags); + __netpoll_cleanup(&nt->np); + spin_lock_irqsave(&target_list_lock, flags); dev_put(nt->np.dev); nt->np.dev = NULL; |