From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alan Jenkins Subject: Re: [PATCH] [RFC] EEE PC hangs when booting off battery Date: Wed, 29 Apr 2009 12:14:33 +0100 Message-ID: <49F83699.3000307@tuffmail.co.uk> References: <49E065CF.6040408@tuffmail.co.uk> <200904140859.02188.bjorn.helgaas@hp.com> <20090414081728.10de978a@infradead.org> <200904140948.37633.bjorn.helgaas@hp.com> <49E5F01B.2060201@tuffmail.co.uk> <49EF0ABD.2080801@tuffmail.co.uk> <49F446AE.6070607@tuffmail.co.uk> <49F6CA0E.5040101@tuffmail.co.uk> (sfid-20090428_111942_198975_13CDA6F5) <1240912688.28835.10.camel@johannes.local> <49F6DA14.7030608@tuffmail.co.uk> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=gamma; h=domainkey-signature:received:received:sender:message-id:date:from :user-agent:mime-version:to:cc:subject:references:in-reply-to :content-type:content-transfer-encoding; bh=9kttKnFt6uZdH6b13zRzSuE8IeBLYoaqIxDRS5JYr2c=; b=Ry9o6UXLrSjxkUrHkqMyFUnwof0L/T5YbDLreCRSsNaEJ1UyIenRZj8hMQ/iQlPqbT 1adZmZ5yf1FVzanTCZgdN5pBuc3uPr+nDs/0U9LR5ndAgdX96YO2FPOIGlF9NFjnfq8+ zwiLvi0ONIJGkr/+BYQPQxGvtyi/5PIEVAYBU= In-Reply-To: <49F6DA14.7030608-cCz0Lq7MMjm9FHfhHBbuYA@public.gmane.org> Sender: linux-wireless-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" To: John Linville Cc: Johannes Berg , "linux-wireless-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Arjan van de Ven , linux-kernel , Kernel Testers List Alan Jenkins wrote: > Johannes Berg wrote: > >> That doesn't seem relevant, this just does some initialisation. However, >> you definitely missed adding a call to wep_free(). >> >> > > Hah, I should have realized something was wrong when I noticed I was > removing more lines that I added. > > The crypto init does cause the module load: > > wait_for_completion > call_usermodehelper_exec > __request_module > crypto_larval_lookup > ? extract_entropy > crypto_alg_mod_lookup > crypto_alloc_base > ieee80211_wep_init > ieee80211_register_hw > Here's a corrected patch complete with changelog. If there are no other problems with it, can you please apply this for 2.6.30 to keep my EeePC regression-free? Thanks Alan ------> >From c5e9dc036247e70956d1a28e8850c3810385dda0 Mon Sep 17 00:00:00 2001 From: Alan Jenkins Date: Wed, 29 Apr 2009 11:41:24 +0100 Subject: [PATCH] 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 --- net/mac80211/main.c | 19 +++++++++---------- 1 files changed, 9 insertions(+), 10 deletions(-) diff --git a/net/mac80211/main.c b/net/mac80211/main.c index fbcbed6..00968c2 100644 --- a/net/mac80211/main.c +++ b/net/mac80211/main.c @@ -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); -- 1.5.4.3 -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html