mac80211: fix modprobe deadlock by not calling wep_init under rtnl_lock

- ieee80211_wep_init(), which is called with rtnl_lock held, blocks in
   request_module() [waiting for modprobe to load a crypto module].

 - modprobe blocks in a call to flush_workqueue(), when it closes a TTY
   [presumably when it exits].

 - The workqueue item linkwatch_event() blocks on rtnl_lock.

There's no reason for wep_init() to be called with rtnl_lock held, so
just move it outside the critical section.

Signed-off-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Alan Jenkins 2009-04-29 11:41:24 +01:00 committed by John W. Linville
parent b7fcb5c4a4
commit d4c4a9a1bc

View File

@ -909,6 +909,13 @@ int ieee80211_register_hw(struct ieee80211_hw *hw)
if (result < 0)
goto fail_sta_info;
result = ieee80211_wep_init(local);
if (result < 0) {
printk(KERN_DEBUG "%s: Failed to initialize wep: %d\n",
wiphy_name(local->hw.wiphy), result);
goto fail_wep;
}
rtnl_lock();
result = dev_alloc_name(local->mdev, local->mdev->name);
if (result < 0)
@ -930,14 +937,6 @@ int ieee80211_register_hw(struct ieee80211_hw *hw)
goto fail_rate;
}
result = ieee80211_wep_init(local);
if (result < 0) {
printk(KERN_DEBUG "%s: Failed to initialize wep: %d\n",
wiphy_name(local->hw.wiphy), result);
goto fail_wep;
}
/* add one default STA interface if supported */
if (local->hw.wiphy->interface_modes & BIT(NL80211_IFTYPE_STATION)) {
result = ieee80211_if_add(local, "wlan%d", NULL,
@ -967,13 +966,13 @@ int ieee80211_register_hw(struct ieee80211_hw *hw)
return 0;
fail_wep:
rate_control_deinitialize(local);
fail_rate:
unregister_netdevice(local->mdev);
local->mdev = NULL;
fail_dev:
rtnl_unlock();
ieee80211_wep_free(local);
fail_wep:
sta_info_stop(local);
fail_sta_info:
debugfs_hw_del(local);