Comment 4 for bug 715318

[ 326.030107] usb 4-1: new full speed USB device using uhci_hcd and address 2
[ 326.486825] input: Plantronics Plantronics .Audio 646 DSP as /devices/pci0000:00/0000:00:1a.1/usb4/4-1/4-1:1.3/input/input10
[ 326.487127] generic-usb 0003:047F:C001.0002: input,hiddev96,hidraw1: USB HID v1.00 Device [Plantronics Plantronics .Audio 646 DSP] on usb-0000:00:1a.1-1/input3
[ 326.534574] 2:1:1: endpoint lacks sample rate attribute bit, cannot set.
[ 326.536551] 2:2:1: endpoint lacks sample rate attribute bit, cannot set.
[ 326.591457] usbcore: registered new interface driver snd-usb-audio
[ 326.658655] 2:1:1: endpoint lacks sample rate attribute bit, cannot set.
[ 326.667640] 2:2:1: endpoint lacks sample rate attribute bit, cannot set.
[ 326.694685] 2:2:1: endpoint lacks sample rate attribute bit, cannot set.
[ 326.699725] 2:1:1: endpoint lacks sample rate attribute bit, cannot set.
[ 326.730675] 2:2:1: endpoint lacks sample rate attribute bit, cannot set.
[ 327.040229] usb 4-1: USB disconnect, address 2
[ 327.043831] BUG: unable to handle kernel NULL pointer dereference at 0000000000000098
[ 327.043846] IP: [<ffffffffa0de2a6b>] snd_complete_urb+0x6b/0xd0 [snd_usb_audio]
[ 327.043871] PGD 11a5ba067 PUD 127f31067 PMD 0
[ 327.043883] Oops: 0000 [#1] SMP
[ 327.043890] last sysfs file: /sys/devices/pci0000:00/0000:00:1a.1/usb4/4-1/4-1:1.0/sound/card1/uevent
[ 327.043899] CPU 1
[ 327.043902] Modules linked in: snd_usb_audio snd_usbmidi_lib binfmt_misc ip6table_filter ip6_tables ipt_MASQUERADE iptable_nat nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_state nf_conntrack ipt_REJECT xt_tcpudp iptable_filter ip_tables x_tables bridge stp kvm_intel kvm parport_pc ppdev dm_crypt snd_hda_codec_idt nvidia(P) snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_seq_midi snd_rawmidi lib80211_crypt_tkip snd_seq_midi_event wl(P) snd_seq dell_wmi_aio dcdbas psmouse serio_raw joydev snd_timer snd_seq_device snd lp soundcore lib80211 snd_page_alloc parport usbhid sdhci_pci hid video output ahci libahci r8169 mii sdhci led_class firewire_ohci firewire_core crc_itu_t intel_agp
[ 327.044021]
[ 327.044029] Pid: 1773, comm: xfce4-power-man Tainted: P 2.6.35-25-generic #44-Ubuntu 0T808J/Vostro 1520
[ 327.044036] RIP: 0010:[<ffffffffa0de2a6b>] [<ffffffffa0de2a6b>] snd_complete_urb+0x6b/0xd0 [snd_usb_audio]
[ 327.044056] RSP: 0000:ffff880001f03d08 EFLAGS: 00010002
[ 327.044062] RAX: 0000000000000200 RBX: ffff880037a69aa0 RCX: 0000000000000002
[ 327.044068] RDX: ffff88012744af00 RSI: 0000000000000000 RDI: ffff88012744af00
[ 327.044074] RBP: ffff880001f03d28 R08: 0000000000000206 R09: ffff88003780a930
[ 327.044080] R10: ffff880136004e90 R11: 0000000000000001 R12: ffff880037a69bb8
[ 327.044086] R13: ffff88012744af00 R14: 0000000000000000 R15: ffff880137155000
[ 327.044093] FS: 00007fddc8f47920(0000) GS:ffff880001f00000(0000) knlGS:0000000000000000
[ 327.044101] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 327.044107] CR2: 0000000000000098 CR3: 000000011a5b3000 CR4: 00000000000406e0
[ 327.044113] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 327.044120] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[ 327.044127] Process xfce4-power-man (pid: 1773, threadinfo ffff88011a78c000, task ffff88011a4496e0)
[ 327.044132] Stack:
[ 327.044136] ffff88012744af00 ffff880137155000 0000000000000000 ffff88003780b7b0
[ 327.044146] <0> ffff880001f03d58 ffffffff81406234 ffff880001f03d58 ffff88003780b780
[ 327.044156] <0> ffff8801371551a0 ffff88012744af00 ffff880001f03db8 ffffffff814279c5
[ 327.044169] Call Trace:
[ 327.044174] <IRQ>
[ 327.044188] [<ffffffff81406234>] usb_hcd_giveback_urb+0x64/0xe0
[ 327.044198] [<ffffffff814279c5>] uhci_giveback_urb+0xb5/0x250
[ 327.044207] [<ffffffff81427e97>] uhci_scan_qh+0x257/0x480
[ 327.044218] [<ffffffff8158aa89>] ? _raw_spin_unlock_bh+0x19/0x20
[ 327.044226] [<ffffffff814282bd>] uhci_scan_schedule+0x18d/0x2f0
[ 327.044239] [<ffffffff810ceb77>] ? rcu_report_qs_rnp+0x77/0x130
[ 327.044248] [<ffffffff8142a571>] uhci_irq+0x81/0x1b0
[ 327.044256] [<ffffffff81405880>] usb_hcd_irq+0x40/0x90
[ 327.044265] [<ffffffff810c9d10>] handle_IRQ_event+0x50/0x160
[ 327.044274] [<ffffffff81067958>] ? __do_softirq+0x118/0x1f0
[ 327.044283] [<ffffffff810cc5c9>] handle_fasteoi_irq+0x89/0x110
[ 327.044293] [<ffffffff8100cb12>] handle_irq+0x22/0x30
[ 327.044302] [<ffffffff815921ec>] do_IRQ+0x6c/0xf0
[ 327.044311] [<ffffffff8158add3>] ret_from_intr+0x0/0x11
[ 327.044316] <EOI>
[ 327.044320] Code: f0 0f b3 93 80 00 00 00 85 c0 75 64 48 8b 1c 24 4c 8b 64 24 08 4c 8b 6c 24 10 4c 8b 74 24 18 c9 c3 eb 05 90 90 90 90 90 48 89 fa <49> 8b b6 98 00 00 00 48 89 df ff 93 70 02 00 00 85 c0 75 ba f6
[ 327.044408] RIP [<ffffffffa0de2a6b>] snd_complete_urb+0x6b/0xd0 [snd_usb_audio]
[ 327.044426] RSP <ffff880001f03d08>
[ 327.044430] CR2: 0000000000000098