From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mathias Kretschmer Subject: Re: mISDN: WARNING: at kernel/softirq.c:124 local_bh_enable+0x8f/0xb0() Date: Tue, 23 Jun 2009 00:37:41 +0200 Message-ID: <200906230037.42412.posting@blx4.net> References: <20090603190952.2dd0cc70.sfr@canb.auug.org.au> <200906051201.04185.isdn@linux-pingi.de> <200906091505.31537.kernel@linux-pingi.de> Mime-Version: 1.0 Content-Type: Multipart/Mixed; boundary="Boundary-00=_2eAQKXpXn+mtmtX" Cc: netdev@vger.kernel.org, Andrew Morton , linux-kernel@vger.kernel.org To: Karsten Keil Return-path: In-Reply-To: <200906091505.31537.kernel@linux-pingi.de> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org --Boundary-00=_2eAQKXpXn+mtmtX Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Hi Karsten, applied your patch. Not sure if it fixed anything, though. Attached is another call trace which looks slightly different. Cheers, Mathias On Tuesday 09 June 2009 15:05:31 Karsten Keil wrote: > On Freitag, 5. Juni 2009 12:01:03 Karsten Keil wrote: > > Hi, > > > > I'm currently see this too from time to time, but have no idea about it. > > ... > > > > > [88563.318126] ------------[ cut here ]------------ > > > > [88563.318129] WARNING: at kernel/softirq.c:124 > > > > local_bh_enable+0x8f/0xb0() [88563.318130] Hardware name: empty > > > > [88563.318132] Modules linked in: usbtouchscreen dvb_usb_cinergyT2 > > > > dummy bonding snd_emu10k1 snd_rawmidi snd_ac97_codec ath9k ac97_bus > > > > snd_pcm snd_page_alloc snd_util_mem forcedeth snd_hwdep > > > > [88563.318141] Pid: 826, comm: mISDN_hfc-pci.1 Not tainted > > > > 2.6.29.4-grsec #13 [88563.318142] Call Trace: > > > > [88563.318147] [] warn_slowpath+0xea/0x160 > > > > [88563.318149] [] local_bh_enable+0x8f/0xb0 > > > > [88563.318152] [] sk_filter+0x44/0xa0 > > > > [88563.318154] [] sock_queue_rcv_skb+0x5d/0x120 > > > > [88563.318156] [] mISDN_send+0x4f/0xa0 > > > > [88563.318159] [] l2up_create+0x7e/0x100 > > > > [88563.318161] [] l2_got_tei+0x0/0x90 > > > > [88563.318163] [] l2_got_tei+0x42/0x90 > > > > [88563.318164] [] mISDN_FsmEvent+0x82/0x100 > > > > [88563.318167] [] tei_id_assign+0x0/0x120 > > > > [88563.318168] [] mISDN_FsmEvent+0x82/0x100 > > > > [88563.318170] [] mgr_send+0x4d3/0x660 > > OK found it, it was in a inlined function call ph_data_ind() in mgr_send(). > > This patch should fix it (will send it upstream later). > > > From: Karsten Keil > Date: Tue, 9 Jun 2009 14:38:39 +0200 > Subject: [PATCH] mISDN: Do not disable IRQ in ph_data_ind() > > > This fix triggering the WARN_ON_ONCE(in_irq() || irqs_disabled()); in > local_bh_enable(). > > Here is no need to grab this lock, this was wrong at all and may > cause a deadlock and access to freed memory, since on a TEI remove > the current listelement can be deleted under us. So this is clearly > a case for list_for_each_entry_safe. > > Signed-off-by: Karsten Keil > --- > drivers/isdn/mISDN/tei.c | 7 ++----- > 1 files changed, 2 insertions(+), 5 deletions(-) > > diff --git a/drivers/isdn/mISDN/tei.c b/drivers/isdn/mISDN/tei.c > index bfcdd97..e04bad6 100644 > --- a/drivers/isdn/mISDN/tei.c > +++ b/drivers/isdn/mISDN/tei.c > @@ -862,8 +862,7 @@ static int > ph_data_ind(struct manager *mgr, struct sk_buff *skb) > { > int ret = -EINVAL; > - struct layer2 *l2; > - u_long flags; > + struct layer2 *l2, *nl2; > u_char mt; > > if (skb->len < 8) { > @@ -908,11 +907,9 @@ ph_data_ind(struct manager *mgr, struct sk_buff *skb) > new_tei_req(mgr, &skb->data[4]); > goto done; > } > - read_lock_irqsave(&mgr->lock, flags); > - list_for_each_entry(l2, &mgr->layer2, list) { > + list_for_each_entry_safe(l2, nl2, &mgr->layer2, list) { > tei_ph_data_ind(l2->tm, mt, &skb->data[4], skb->len - 4); > } > - read_unlock_irqrestore(&mgr->lock, flags); > done: > return ret; > } --Boundary-00=_2eAQKXpXn+mtmtX Content-Type: text/plain; charset="utf-8"; name="misdn.txt" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename="misdn.txt" Jun 21 21:49:27 [kernel] [ 202.818502] ------------[ cut here ]------------ Jun 21 21:49:27 [kernel] [ 202.818520] WARNING: at kernel/softirq.c:141 local_bh_enable+0x8b/0xb0() Jun 21 21:49:27 [kernel] [ 202.818525] Hardware name: empty Jun 21 21:49:27 [kernel] [ 202.818528] Modules linked in: iscsi_trgt dummy bonding forcedeth usbtouchscreen Jun 21 21:49:27 [kernel] [ 202.818542] Pid: 811, comm: mISDN_hfc-pci.1 Not tainted 2.6.30 #6 Jun 21 21:49:27 [kernel] [ 202.818546] Call Trace: Jun 21 21:49:27 [kernel] [ 202.818556] [] ? local_bh_enable+0x8b/0xb0 Jun 21 21:49:27 [kernel] [ 202.818562] [] ? local_bh_enable+0x8b/0xb0 Jun 21 21:49:27 [kernel] [ 202.818572] [] ? warn_slowpath_common+0x79/0xd0 Jun 21 21:49:27 [kernel] [ 202.818578] [] ? local_bh_enable+0x8b/0xb0 Jun 21 21:49:27 [kernel] [ 202.818587] [] ? sk_filter+0x44/0xa0 Jun 21 21:49:27 [kernel] [ 202.818594] [] ? sock_queue_rcv_skb+0x5d/0x120 Jun 21 21:49:27 [kernel] [ 202.818604] [] ? mISDN_send+0x4f/0xa0 Jun 21 21:49:27 [kernel] [ 202.818610] [] ? l2_got_ui+0x0/0x70 Jun 21 21:49:27 [kernel] [ 202.818617] [] ? l2up+0x27/0x50 Jun 21 21:49:27 [kernel] [ 202.818623] [] ? mISDN_FsmEvent+0x82/0x100 Jun 21 21:49:27 [kernel] [ 202.818630] [] ? l2_send+0x6fa/0x980 Jun 21 21:49:27 [kernel] [ 202.818636] [] ? l2_pull_iqueue+0x0/0x310 Jun 21 21:49:27 [kernel] [ 202.818643] [] ? mgr_bcast+0x83/0x160 Jun 21 21:49:27 [kernel] [ 202.818649] [] ? mISDNStackd+0x429/0x670 Jun 21 21:49:27 [kernel] [ 202.818657] [] ? autoremove_wake_function+0x0/0x30 Jun 21 21:49:27 [kernel] [ 202.818663] [] ? mISDNStackd+0x0/0x670 Jun 21 21:49:27 [kernel] [ 202.818668] [] ? mISDNStackd+0x0/0x670 Jun 21 21:49:27 [kernel] [ 202.818674] [] ? kthread+0x54/0x90 Jun 21 21:49:27 [kernel] [ 202.818681] [] ? child_rip+0xa/0x20 Jun 21 21:49:27 [kernel] [ 202.818687] [] ? kthread+0x0/0x90 Jun 21 21:49:27 [kernel] [ 202.818692] [] ? child_rip+0x0/0x20 Jun 21 21:49:27 [kernel] [ 202.818696] ---[ end trace d74f848acdfc6568 ]--- --Boundary-00=_2eAQKXpXn+mtmtX--