From 0ad0c3c64484b1458b51167bd3e614d8d9d070f8 Mon Sep 17 00:00:00 2001 From: James Ketrenos Date: Wed, 21 Sep 2005 11:54:15 -0500 Subject: [PATCH] ieee80211: Fix kernel Oops when module unload tree b69e983266840983183a00f5ac02c66d5270ca47 parent cdd6372949b76694622ed74fe36e1dd17a92eb71 author Zhu Yi 1124435425 -0500 committer James Ketrenos 1127312421 -0500 Fix kernel Oops when module unload. Export a new function ieee80211_crypt_quiescing from ieee80211. Device drivers call it to make the host crypto stack enter the quiescence state, which means "process existing requests, but don't accept new ones". This is usually called during a driver's host crypto data structure free (module unload) path. Signed-off-by: James Ketrenos Signed-off-by: Jeff Garzik --- net/ieee80211/ieee80211_crypt.c | 33 +++++++++++++++++++++++++++------ net/ieee80211/ieee80211_module.c | 2 ++ 2 files changed, 29 insertions(+), 6 deletions(-) (limited to 'net') diff --git a/net/ieee80211/ieee80211_crypt.c b/net/ieee80211/ieee80211_crypt.c index 0c36629..60d3166 100644 --- a/net/ieee80211/ieee80211_crypt.c +++ b/net/ieee80211/ieee80211_crypt.c @@ -44,6 +44,10 @@ void ieee80211_crypt_deinit_entries(struct ieee80211_device *ieee, int force) unsigned long flags; spin_lock_irqsave(&ieee->lock, flags); + + if (list_empty(&ieee->crypt_deinit_list)) + goto unlock; + for (ptr = ieee->crypt_deinit_list.next, n = ptr->next; ptr != &ieee->crypt_deinit_list; ptr = n, n = ptr->next) { entry = list_entry(ptr, struct ieee80211_crypt_data, list); @@ -59,21 +63,35 @@ void ieee80211_crypt_deinit_entries(struct ieee80211_device *ieee, int force) } kfree(entry); } + unlock: + spin_unlock_irqrestore(&ieee->lock, flags); +} + +/* After this, crypt_deinit_list won't accept new members */ +void ieee80211_crypt_quiescing(struct ieee80211_device *ieee) +{ + unsigned long flags; + + spin_lock_irqsave(&ieee->lock, flags); + ieee->crypt_quiesced = 1; spin_unlock_irqrestore(&ieee->lock, flags); } void ieee80211_crypt_deinit_handler(unsigned long data) { struct ieee80211_device *ieee = (struct ieee80211_device *)data; + unsigned long flags; ieee80211_crypt_deinit_entries(ieee, 0); - if (!list_empty(&ieee->crypt_deinit_list)) { + + spin_lock_irqsave(&ieee->lock, flags); + if (!list_empty(&ieee->crypt_deinit_list) && !ieee->crypt_quiesced) { printk(KERN_DEBUG "%s: entries remaining in delayed crypt " "deletion list\n", ieee->dev->name); ieee->crypt_deinit_timer.expires = jiffies + HZ; add_timer(&ieee->crypt_deinit_timer); } - + spin_unlock_irqrestore(&ieee->lock, flags); } void ieee80211_crypt_delayed_deinit(struct ieee80211_device *ieee, @@ -93,10 +111,12 @@ void ieee80211_crypt_delayed_deinit(struct ieee80211_device *ieee, * locking. */ spin_lock_irqsave(&ieee->lock, flags); - list_add(&tmp->list, &ieee->crypt_deinit_list); - if (!timer_pending(&ieee->crypt_deinit_timer)) { - ieee->crypt_deinit_timer.expires = jiffies + HZ; - add_timer(&ieee->crypt_deinit_timer); + if (!ieee->crypt_quiesced) { + list_add(&tmp->list, &ieee->crypt_deinit_list); + if (!timer_pending(&ieee->crypt_deinit_timer)) { + ieee->crypt_deinit_timer.expires = jiffies + HZ; + add_timer(&ieee->crypt_deinit_timer); + } } spin_unlock_irqrestore(&ieee->lock, flags); } @@ -250,6 +270,7 @@ static void __exit ieee80211_crypto_deinit(void) EXPORT_SYMBOL(ieee80211_crypt_deinit_entries); EXPORT_SYMBOL(ieee80211_crypt_deinit_handler); EXPORT_SYMBOL(ieee80211_crypt_delayed_deinit); +EXPORT_SYMBOL(ieee80211_crypt_quiescing); EXPORT_SYMBOL(ieee80211_register_crypto_ops); EXPORT_SYMBOL(ieee80211_unregister_crypto_ops); diff --git a/net/ieee80211/ieee80211_module.c b/net/ieee80211/ieee80211_module.c index 4b43ae1..82a4fd7 100644 --- a/net/ieee80211/ieee80211_module.c +++ b/net/ieee80211/ieee80211_module.c @@ -138,6 +138,7 @@ struct net_device *alloc_ieee80211(int sizeof_priv) init_timer(&ieee->crypt_deinit_timer); ieee->crypt_deinit_timer.data = (unsigned long)ieee; ieee->crypt_deinit_timer.function = ieee80211_crypt_deinit_handler; + ieee->crypt_quiesced = 0; spin_lock_init(&ieee->lock); @@ -161,6 +162,7 @@ void free_ieee80211(struct net_device *dev) int i; + ieee80211_crypt_quiescing(ieee); del_timer_sync(&ieee->crypt_deinit_timer); ieee80211_crypt_deinit_entries(ieee, 1); -- cgit v1.1