Can't disconnect a USB sound device and connect another

[Victor Hahn <victor@open-bash.org>]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

... because it causes lsusb to freeze and gives me this in /var/log/messages:

Dec 23 23:27:04 cabrio kernel: usb 2-2: USB disconnect, address 5
Dec 23 23:27:04 cabrio kernel: PGD 110f2067 PUD 110f3067 PMD 0
Dec 23 23:27:04 cabrio kernel: CPU 0
Dec 23 23:27:04 cabrio kernel: Modules linked in: videodev v4l2_common 
v4l1_compat snd_rtctimer binfmt_misc rfcomm l2cap bluetooth capability 
commoncap ppdev powernow_k8 cpufreq_userspace cpufreq_stats cpufreq_powersave 
cpufreq_ondemand freq_table cpufreq_conservative video output sbs container 
dock ac battery ext3 jbd mbcache aes_x86_64 ipv6 it87 hwmon_vid parport_pc lp 
parport loop snd_mpu401 snd_mpu401_uart snd_usb_audio snd_pcm_oss 
snd_mixer_oss snd_pcm snd_seq_dummy snd_page_alloc snd_usb_lib snd_hwdep 
snd_seq_oss analog gameport snd_seq_midi snd_rawmidi snd_seq_midi_event 
snd_seq snd_timer snd_seq_device snd psmouse button soundcore serio_raw 
i2c_nforce2 k8temp i2c_core pcspkr af_packet shpchp pci_hotplug evdev xfs 
sha256 twofish_x86_64 twofish_common cbc blkcipher sg ide_cd cdrom sd_mod 
usbhid hid sata_nv 8139too floppy ata_generic 8139cp mii libata scsi_mod 
amd74xx ide_core forcedeth ehci_hcd ohci_hcd usbcore dm_crypt dm_mirror 
dm_snapshot dm_mod thermal processor fan fuse
Dec 23 23:27:04 cabrio kernel: Pid: 2052, comm: khubd Not tainted 2.6.23.11 #1
Dec 23 23:27:04 cabrio kernel: RIP: 0010:[_end+130488219/2130651808]  
[_end+130488219/2130651808] :snd:snd_ctl_dev_disconnect+0x6b/0xb0
Dec 23 23:27:04 cabrio kernel: RSP: 0018:ffff810037bfdc40  EFLAGS: 00010282
Dec 23 23:27:04 cabrio kernel: RAX: 0000000000000000 RBX: 0000000000100100 
RCX: 0000000000000018
Dec 23 23:27:04 cabrio kernel: RDX: 0000000000020004 RSI: 000000000000001d 
RDI: ffff810013e98c08
Dec 23 23:27:04 cabrio kernel: RBP: ffff8100394631a8 R08: ffff810037bfc000 
R09: 0000000000000000
Dec 23 23:27:04 cabrio kernel: R10: 0000000000000000 R11: ffffffff88281910 
R12: ffff810039463000
Dec 23 23:27:04 cabrio kernel: R13: ffff810039463168 R14: 0000000000000000 
R15: ffff810039463000
Dec 23 23:27:04 cabrio kernel: FS:  00002b24912551e0(0000) GS:ffffffff80533000
(0000) knlGS:00000000f74b16c0
Dec 23 23:27:04 cabrio kernel: CS:  0010 DS: 0018 ES: 0018 CR0: 
000000008005003b
Dec 23 23:27:04 cabrio kernel: CR2: 0000000000100100 CR3: 00000000110f1000 
CR4: 00000000000006e0
Dec 23 23:27:04 cabrio kernel: DR0: 0000000000000000 DR1: 0000000000000000 
DR2: 0000000000000000
Dec 23 23:27:04 cabrio kernel: DR3: 0000000000000000 DR6: 00000000ffff0ff0 
DR7: 0000000000000400
Dec 23 23:27:04 cabrio kernel: Process khubd (pid: 2052, threadinfo 
ffff810037bfc000, task ffff81003d67d0c0)
Dec 23 23:27:04 cabrio kernel: Stack:  0000000000000000 ffff810038850d00 
ffff810039463000 ffff810039463150
Dec 23 23:27:04 cabrio kernel:  0000000000000000 ffffffff88281e69 
ffff810038850d00 ffffffff882821ac
Dec 23 23:27:04 cabrio kernel:  0000000000000000 0000000000000000 
ffff810039463000 ffff8100394631e0
Dec 23 23:27:04 cabrio kernel: Call Trace:
Dec 23 23:27:04 cabrio kernel:  
[_end+130500873/2130651808] :snd:snd_device_disconnect+0x59/0x90
Dec 23 23:27:04 cabrio kernel:  
[_end+130501708/2130651808] :snd:snd_device_disconnect_all+0x3c/0x70
Dec 23 23:27:04 cabrio kernel:  
[_end+130481675/2130651808] :snd:snd_card_disconnect+0x15b/0x1a0
Dec 23 23:27:04 cabrio kernel:  
[_end+131093678/2130651808] :snd_usb_audio:usb_audio_disconnect+0xae/0x1a0
Dec 23 23:27:04 cabrio kernel:  
[_end+128211869/2130651808] :usbcore:usb_unbind_interface+0x6d/0xe0
Dec 23 23:27:04 cabrio kernel:  [__device_release_driver+130/192] 
__device_release_driver+0x82/0xc0
Dec 23 23:27:04 cabrio kernel:  [device_release_driver+51/96] 
device_release_driver+0x33/0x60
Dec 23 23:27:04 cabrio kernel:  [bus_remove_device+118/176] 
bus_remove_device+0x76/0xb0
Dec 23 23:27:04 cabrio kernel:  [device_del+417/736] device_del+0x1a1/0x2e0
Dec 23 23:27:04 cabrio kernel:  
[_end+128198657/2130651808] :usbcore:usb_disable_device+0x91/0x110
Dec 23 23:27:04 cabrio kernel:  
[_end+128179466/2130651808] :usbcore:usb_disconnect+0xaa/0x150
Dec 23 23:27:04 cabrio kernel:  
[_end+128181649/2130651808] :usbcore:hub_thread+0x401/0xe30
Dec 23 23:27:04 cabrio kernel:  [thread_return+87/1463] 
thread_return+0x57/0x5b7
Dec 23 23:27:04 cabrio kernel:  [autoremove_wake_function+0/48] 
autoremove_wake_function+0x0/0x30
Dec 23 23:27:04 cabrio kernel:  
[_end+128180624/2130651808] :usbcore:hub_thread+0x0/0xe30
Dec 23 23:27:04 cabrio kernel:  [kthread+75/128] kthread+0x4b/0x80
Dec 23 23:27:04 cabrio kernel:  [child_rip+10/18] child_rip+0xa/0x12
Dec 23 23:27:04 cabrio kernel:  [kthread+0/128] kthread+0x0/0x80
Dec 23 23:27:04 cabrio kernel:  [child_rip+0/18] child_rip+0x0/0x12
Dec 23 23:27:04 cabrio kernel:
Dec 23 23:27:04 cabrio kernel:
Dec 23 23:27:04 cabrio kernel: Code: 48 8b 03 0f 18 08 48 39 eb 75 ca 4c 89 ef 
e8 d2 35 fd f7 ba
Dec 23 23:27:04 cabrio kernel:  RSP <ffff810037bfdc40>

Is there a way to exchange USB audio devices without rebooting?

Beste regards,
Victor
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.6 (GNU/Linux)

iD8DBQFHbuLhX/S6KpIOqB0RAqbsAJ9IGmNHrIX1uqJqhgtIJDO4tcNzGgCfeZgp
G+dpTDupwAQRyV76nm3/qC4=
=Es5+
-----END PGP SIGNATURE-----
--
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/