Same here using a Dell Latitude E6400 with an nvidia quadro 160M and an Intel WiFi 5100.
Bug always happen under heavy use of WPA wifi network.

Nov  1 22:04:09 ithil kernel: [ 2042.313640] BUG: scheduling while atomic: swapper/0/0x00000100
Nov  1 22:04:09 ithil kernel: [ 2042.313656] Modules linked in: ipv6 af_packet sco rfcomm bridge stp bnep l2cap bluetooth ppdev sbs sbshc container pci_slot acpi_cpufreq cpufreq_powersave cpufreq_userspace cpufreq_stats cpufreq_conservative cpufreq_ondemand freq_table iptable_filter ip_tables x_tables sbp2 parport_pc lp parport arc4 ecb joydev crypto_blkcipher iwlagn iwlcore snd_hda_intel rfkill snd_pcm_oss led_class snd_mixer_oss dcdbas serio_raw mac80211 evdev snd_pcm psmouse snd_seq_dummy cfg80211 snd_seq_oss pcspkr nvidia(P) snd_seq_midi i2c_core sdhci_pci video snd_rawmidi output sdhci snd_seq_midi_event mmc_core wmi ricoh_mmc snd_seq battery button ac snd_timer snd_seq_device snd soundcore intel_agp agpgart snd_page_alloc shpchp pci_hotplug ext3 jbd mbcache sr_mod cdrom sd_mod crc_t10dif sg usbhid hid ahci libata scsi_mod dock ohci1394 uhci_hcd ehci_hcd ieee1394 e1000e usbcore thermal processor fan fbcon tileblit font bitblit softcursor fuse
Nov  1 22:04:09 ithil kernel: [ 2042.313848] 
Nov  1 22:04:09 ithil kernel: [ 2042.313855] Pid: 0, comm: swapper Tainted: P          (2.6.27-7-generic #1)
Nov  1 22:04:09 ithil kernel: [ 2042.313861] EIP: 0060:[<f885e800>] EFLAGS: 00000246 CPU: 1
Nov  1 22:04:09 ithil kernel: [ 2042.313878] EIP is at acpi_idle_enter_bm+0x268/0x2b7 [processor]
Nov  1 22:04:09 ithil kernel: [ 2042.313885] EAX: c0510760 EBX: 00000415 ECX: 00000000 EDX: 013f2000
Nov  1 22:04:09 ithil kernel: [ 2042.313890] ESI: 00000000 EDI: 0094f86a EBP: f7477f80 ESP: f7477f64
Nov  1 22:04:09 ithil kernel: [ 2042.313895]  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
Nov  1 22:04:09 ithil kernel: [ 2042.313901] CR0: 8005003b CR2: b6d13000 CR3: 00515000 CR4: 00000690
Nov  1 22:04:09 ithil kernel: [ 2042.313906] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
Nov  1 22:04:09 ithil kernel: [ 2042.313911] DR6: ffff0ff0 DR7: 00000400
Nov  1 22:04:09 ithil kernel: [ 2042.313917]  [<c02dbf7b>] cpuidle_idle_call+0x7b/0xd0
Nov  1 22:04:09 ithil kernel: [ 2042.313930]  [<c010288d>] cpu_idle+0x7d/0x140
Nov  1 22:04:09 ithil kernel: [ 2042.313939]  [<c037a661>] start_secondary+0x9d/0xcc
Nov  1 22:04:09 ithil kernel: [ 2042.313952]  =======================
Nov  1 22:04:09 ithil kernel: [ 2042.313957] bad: scheduling from the idle thread!
Nov  1 22:04:09 ithil kernel: [ 2042.313964] Pid: 0, comm: swapper Tainted: P          2.6.27-7-generic #1
Nov  1 22:04:09 ithil kernel: [ 2042.313971]  [<c037c406>] ? printk+0x1d/0x1f
Nov  1 22:04:09 ithil kernel: [ 2042.313980]  [<c0122b8a>] dequeue_task_idle+0x2a/0x40
Nov  1 22:04:09 ithil kernel: [ 2042.313988]  [<c012107f>] dequeue_task+0xcf/0x130
Nov  1 22:04:09 ithil kernel: [ 2042.313998]  [<c012112a>] deactivate_task+0x1a/0x30
Nov  1 22:04:09 ithil kernel: [ 2042.314006]  [<c037ca23>] schedule+0x4b3/0x790
Nov  1 22:04:09 ithil kernel: [ 2042.314015]  [<c012b6ab>] ? default_wake_function+0xb/0x10
Nov  1 22:04:09 ithil kernel: [ 2042.314025]  [<c037e511>] ? _spin_lock_irqsave+0x31/0x40
Nov  1 22:04:09 ithil kernel: [ 2042.314034]  [<c013c91c>] ? __mod_timer+0xac/0xf0
Nov  1 22:04:09 ithil kernel: [ 2042.314044]  [<c037d0a4>] schedule_timeout+0x84/0xf0
Nov  1 22:04:09 ithil kernel: [ 2042.314052]  [<c013c260>] ? process_timeout+0x0/0x10
Nov  1 22:04:09 ithil kernel: [ 2042.314061]  [<c037d09f>] ? schedule_timeout+0x7f/0xf0
Nov  1 22:04:09 ithil kernel: [ 2042.314070]  [<c037d12a>] schedule_timeout_uninterruptible+0x1a/0x20
Nov  1 22:04:09 ithil kernel: [ 2042.314078]  [<c013c97d>] msleep+0x1d/0x30
Nov  1 22:04:09 ithil kernel: [ 2042.314087]  [<f8c20ceb>] iwl_scan_cancel_timeout+0x4b/0x80 [iwlcore]
Nov  1 22:04:09 ithil kernel: [ 2042.314109]  [<f8b99eb2>] iwl4965_mac_update_tkip_key+0x32/0xe0 [iwlagn]
Nov  1 22:04:09 ithil kernel: [ 2042.314125]  [<f8bdf10e>] ? tkip_mixing_phase1+0xe/0x140 [mac80211]
Nov  1 22:04:09 ithil kernel: [ 2042.314157]  [<f8bdf59c>] ieee80211_tkip_decrypt_data+0x16c/0x210 [mac80211]
Nov  1 22:04:09 ithil kernel: [ 2042.314188]  [<c014e63b>] ? getnstimeofday+0x4b/0x100
Nov  1 22:04:09 ithil kernel: [ 2042.314199]  [<c0136976>] ? set_normalized_timespec+0x16/0x90
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