From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Paul E. McKenney" Subject: Re: scheduling while atomic: br2684ctl (atm) Date: Wed, 22 Sep 2010 14:54:51 -0700 Message-ID: <20100922215450.GO2435@linux.vnet.ibm.com> References: <647401.39574.qm@web58406.mail.re3.yahoo.com> Reply-To: paulmck@linux.vnet.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Karl Hiramoto , "David S. Miller" , Chas Williams - CONTRACTOR , netdev@vger.kernel.org, linux-kernel@vger.kernel.org To: Mikko Vinni Return-path: Content-Disposition: inline In-Reply-To: <647401.39574.qm@web58406.mail.re3.yahoo.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Wed, Sep 22, 2010 at 12:42:29AM -0700, Mikko Vinni wrote: > Hi all, > > I get the following message apparently every time (on 2.6.36-rc4+ at least) when > killing any old br2684ctl processes. "unregister_atmdevice_notifier" was added > by > 7313bb8f ("atm: propagate signal changes via notifier") so perhaps the > unregister > part was not tested properly for rcu interaction? This complaint will happen when you call synchronize_rcu() while in some context where it is illegal to block, for example, if irqs are disabled or if a spinlock is held. I don't see commit 7313bb8f, but perhaps unregister_atmdevice_notifier() is holding a spinlock across the call to atomic_notifier_chain_unregister()? Thanx, Paul > So far I haven't noticed any ill effects from the message. Let me know if I > should test something. Thanks. > > Mikko > > > [29874.827053] PM: restore of devices complete after 3623.342 msecs > [29874.827053] wlan0: Trigger new scan to find an IBSS to join > [29875.020370] wlan0: Creating new IBSS network, BSSID 8a:4c:35:ef:eb:6b > [29875.613701] wlan0: no IPv6 routers present > [29876.027033] nas0: no IPv6 routers present > [29876.831216] cxacru 3-1:1.0: receive of cm 0x90 failed (-104) > [29876.844328] r8169 0000:09:00.0: PME# enabled > [29876.878731] snapshot_ioctl: ioctl '4004330c' is deprecated and will be > removed soon, update your suspend-to-disk utilities > [29876.878741] Restarting tasks ... done. > [29876.903718] PM: Basic memory bitmaps freed > [29876.903718] video LNXVIDEO:01: Restoring backlight state > [29879.703963] cxacru 3-1:1.0: found firmware cxacru-fw.bin > [29879.708273] cxacru 3-1:1.0: loading firmware > [29881.277932] cxacru 3-1:1.0: starting device > [29882.346357] cxacru0: ADSL USB MODEM (usb-0000:00:12.0-1) 00:04:ed:09:1e:5a > [29882.362575] ATM dev 0: ADSL state: running > [29882.362593] ATM dev 0: ADSL line: down > [29882.580484] BUG: scheduling while atomic: br2684ctl/28543/0x00000002 > [29882.580498] Modules linked in: nls_cp437 vfat fat usb_storage cpufreq_stats > iptable_filter ipt_MASQUERADE iptable_nat nf_nat nf_conntrack_ipv4 nf_conntrack > nf_defrag_ipv4 ip_tables x_tables br2684 ipv6 sco bnep l2cap bluetooth ext2 > cxacru arc4 ecb usbatm atm uvcvideo videodev v4l1_compat v4l2_compat_ioctl32 > snd_seq_dummy snd_seq_oss snd_hda_codec_atihdmi snd_seq_midi_event > snd_hda_codec_idt snd_seq snd_seq_device ath5k snd_hda_intel snd_pcm_oss > snd_hda_codec snd_mixer_oss mac80211 joydev ath snd_hwdep snd_pcm video ohci_hcd > hp_wmi output snd_timer cfg80211 ehci_hcd hp_accel lis3lv02d battery rfkill > input_polldev snd wmi thermal ohci1394 psmouse jmb38x_ms pcspkr ac edac_core > i2c_piix4 sg soundcore usbcore snd_page_alloc button serio_raw evdev memstick > powernow_k8 led_class r8169 processor k10temp mii ieee1394 mperf rtc_cmos > rtc_core rtc_lib ext4 mbcache jbd2 crc16 sr_mod cdrom sd_mod ahci libahci > pata_atiixp pata_acpi libata scsi_mod radeon ttm drm_kms_helper drm i2c_algo_bit > i2c_core [last unloaded: mmc_core] > [29882.580796] Pid: 28543, comm: br2684ctl Not tainted > 2.6.36-rc4-CUST-00214-g2422084 #49 > [29882.580808] Call Trace: > [29882.580845] [] __schedule_bug+0x61/0x70 > [29882.580865] [] schedule+0x8de/0xa90 > [29882.580882] [] schedule_timeout+0x215/0x350 > [29882.580900] [] ? flush_backlog+0x0/0x120 > [29882.580924] [] ? smp_call_function_single+0x172/0x190 > [29882.580937] [] ? flush_backlog+0x0/0x120 > [29882.580951] [] wait_for_common+0xc0/0x150 > [29882.580968] [] ? default_wake_function+0x0/0x10 > [29882.580985] [] wait_for_completion+0x18/0x20 > [29882.581004] [] synchronize_rcu+0x46/0x50 > [29882.581025] [] ? wakeme_after_rcu+0x0/0x10 > [29882.581051] [] atomic_notifier_chain_unregister+0x60/0x80 > [29882.581083] [] unregister_atmdevice_notifier+0x13/0x20 > [atm] > [29882.581102] [] br2684_push+0x2bd/0x320 [br2684] > [29882.581124] [] vcc_release+0x76/0x130 [atm] > [29882.581142] [] sock_release+0x24/0x90 > [29882.581155] [] sock_close+0x12/0x30 > [29882.581174] [] fput+0xd5/0x230 > [29882.581188] [] filp_close+0x5b/0x80 > [29882.581207] [] put_files_struct+0x97/0x100 > [29882.581221] [] exit_files+0x4d/0x60 > [29882.581234] [] do_exit+0x178/0x810 > [29882.581256] [] ? fpu_finit+0x1c/0x30 > [29882.581270] [] do_group_exit+0x4f/0xb0 > [29882.581283] [] sys_exit_group+0x12/0x20 > [29882.581300] [] system_call_fastpath+0x16/0x1b > [29883.353415] ATM dev 0: ADSL line: initializing > [29884.359446] ATM dev 0: ADSL line: down > [29887.862669] ata3.00: configured for UDMA/100 > [29887.862688] ata3: EH complete > > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/