Noticed in 2.6.9-rc4-mm1, still present in 2.6.9-mm1:
When a usb flash memory key is inserted, I get this report on syslog:

Oct 22 21:40:04 kefk kernel: ehci_hcd 0000:00:1d.7: GetStatus port 3 status 
001803 POWER sig=j  CSC CONNECT
Oct 22 21:40:04 kefk kernel: hub 5-0:1.0: port 3, status 0501, change 0001, 
480 Mb/s
Oct 22 21:40:04 kefk kernel: hub 5-0:1.0: debounce: port 3: total 100ms stable 
100ms status 0x501
Oct 22 21:40:04 kefk kernel: hub 5-0:1.0: port 3 not reset yet, waiting 50ms
Oct 22 21:40:04 kefk kernel: ehci_hcd 0000:00:1d.7: port 3 high speed
Oct 22 21:40:04 kefk kernel: ehci_hcd 0000:00:1d.7: GetStatus port 3 status 
001005 POWER sig=se0  PE CONNECT
Oct 22 21:40:04 kefk kernel: usb 5-3: new high speed USB device using address 
6
Oct 22 21:40:04 kefk kernel: usb 5-3: new device strings: Mfr=1, Product=2, 
SerialNumber=3
Oct 22 21:40:04 kefk kernel: usb 5-3: default language 0x0409
Oct 22 21:40:04 kefk kernel: usb 5-3: Product: Mass storage
Oct 22 21:40:04 kefk kernel: usb 5-3: Manufacturer: USB
Oct 22 21:40:04 kefk kernel: usb 5-3: SerialNumber: 142E19413C2FCA34
Oct 22 21:40:04 kefk kernel: usb 5-3: hotplug
Oct 22 21:40:04 kefk kernel: usb 5-3: adding 5-3:1.0 (config #1, interface 0)
Oct 22 21:40:04 kefk kernel: usb 5-3:1.0: hotplug
Oct 22 21:40:05 kefk kernel: ub: sizeof ub_scsi_cmd 64 ub_dev 964
Oct 22 21:40:05 kefk kernel: ub 5-3:1.0: usb_probe_interface
Oct 22 21:40:05 kefk kernel: ub 5-3:1.0: usb_probe_interface - got id
Oct 22 21:40:05 kefk kernel: uba: device 6 capacity nsec 50 bsize 512
Oct 22 21:40:05 kefk kernel: uba: made changed
Oct 22 21:40:05 kefk kernel: uba: device 6 capacity nsec 1024000 bsize 512
Oct 22 21:40:05 kefk kernel: uba: device 6 capacity nsec 1024000 bsize 512
Oct 22 21:40:05 kefk kernel:  uba: uba1
Oct 22 21:40:05 kefk kernel:  uba: uba1
Oct 22 21:40:05 kefk kernel: kobject_register failed for uba1 (-17)
Oct 22 21:40:05 kefk kernel:  [<c01f1f77>] kobject_register+0x51/0x5f
Oct 22 21:40:05 kefk kernel:  [<c018467c>] add_partition+0xbb/0xf0
Oct 22 21:40:05 kefk kernel:  [<c01847f4>] register_disk+0xee/0x11d
Oct 22 21:40:05 kefk kernel:  [<c024b8e6>] add_disk+0x36/0x41
Oct 22 21:40:05 kefk kernel:  [<c024b89c>] exact_match+0x0/0x7
Oct 22 21:40:05 kefk kernel:  [<c024b8a3>] exact_lock+0x0/0xd
Oct 22 21:40:05 kefk kernel:  [<f8c48e70>] ub_probe+0x291/0x2f4 [ub]
Oct 22 21:40:05 kefk kernel:  [<c0298f0e>] usb_probe_interface+0xb8/0xe1
Oct 22 21:40:05 kefk kernel:  [<c0243274>] bus_match+0x32/0x6a
Oct 22 21:40:05 kefk kernel:  [<c024339c>] driver_attach+0x46/0x85
Oct 22 21:40:05 kefk kernel:  [<c01f1f48>] kobject_register+0x22/0x5f
Oct 22 21:40:05 kefk kernel:  [<c0243800>] bus_add_driver+0x91/0xcb
Oct 22 21:40:05 kefk kernel:  [<c0298fe0>] usb_register+0x49/0x9f
Oct 22 21:40:05 kefk kernel:  [<f8c4d03f>] ub_init+0x3f/0x5f [ub]
Oct 22 21:40:05 kefk kernel:  [<c0131de7>] sys_init_module+0x160/0x246
Oct 22 21:40:05 kefk kernel:  [<c0103d71>] sysenter_past_esp+0x52/0x71
Oct 22 21:40:05 kefk kernel: usbcore: registered new driver ub

After that, uba appears as /dev/uba, but /dev/uba1 is missing. I can create by 
hand /dev/uba1 and access data on flash key, but if I umount and then remove 
the key I get this oops:


Oct 22 21:45:05 kefk kernel: ehci_hcd 0000:00:1d.7: GetStatus port 3 status 
001002 POWER sig=se0  CSC
Oct 22 21:45:05 kefk kernel: hub 5-0:1.0: port 3, status 0100, change 0001, 12 
Mb/s
Oct 22 21:45:05 kefk kernel: usb 5-3: USB disconnect, address 6
Oct 22 21:45:05 kefk kernel: usb 5-3: usb_disable_device nuking all URBs
Oct 22 21:45:05 kefk kernel: usb 5-3: unregistering interface 5-3:1.0
Oct 22 21:45:05 kefk kernel: Unable to handle kernel NULL pointer dereference 
at virtual address 00000050
Oct 22 21:45:05 kefk kernel:  printing eip:
Oct 22 21:45:05 kefk kernel: c01862cf
Oct 22 21:45:05 kefk kernel: *pde = 00000000
Oct 22 21:45:05 kefk kernel: Oops: 0000 [#1]
Oct 22 21:45:05 kefk kernel: PREEMPT SMP
Oct 22 21:45:05 kefk kernel: Modules linked in: nls_cp437 lp parport_pc ub 
hidp hci_usb snd_seq_midi snd_emu10k1_synth snd_emux_synth snd_seq_virmidi 
snd_seq_midi_emul nvidia tun md5 ipv6 rfcomm l2cap bluetooth snd_seq_oss 
snd_seq_midi_event snd_seq snd_pcm_oss snd_mixer_oss snd_emu10k1 snd_rawmidi 
snd_seq_device snd_ac97_codec snd_pcm snd_timer snd_page_alloc snd_util_mem 
snd_hwdep snd soundcore ipt_REJECT iptable_filter ip_tables loop nls_utf8 
ide_cd i2c_dev w83
781d i2c_sensor i2c_isa i2c_i801 isofs zlib_inflate e1000 ppa parport ehci_hcd 
usblp uhci_hcd genrtc
Oct 22 21:45:05 kefk kernel: CPU:    1
Oct 22 21:45:05 kefk kernel: EIP:    0060:[<c01862cf>]    Tainted: P      VLI
Oct 22 21:45:05 kefk kernel: EFLAGS: 00010246   (2.6.9-mm1)
Oct 22 21:45:05 kefk kernel: EIP is at sysfs_remove_dir+0x1d/0xef
Oct 22 21:45:05 kefk kernel: eax: cf85c308   ebx: cf85c308   ecx: c18ff480   
edx: c1000000
Oct 22 21:45:05 kefk kernel: esi: edce7c00   edi: 00000000   ebp: 00000246   
esp: c1bace20
Oct 22 21:45:05 kefk kernel: ds: 007b   es: 007b   ss: 0068
Oct 22 21:45:05 kefk kernel: Process khubd (pid: 125, threadinfo=c1bac000 
task=c1baba40)
Oct 22 21:45:05 kefk kernel: Stack: 00000000 cf85c308 edce7c00 00000001 
00000246 c01f2087 cf85c308 c01f2097
Oct 22 21:45:05 kefk kernel:        cca37180 c01849fc 00000000 edce7c00 
00000000 00000246 f8c48ff1 dc3ac848
Oct 22 21:45:05 kefk kernel:        0000003c 00000003 cca37294 f74ff02c 
cca37180 cca37280 f8c4b220 c86ad000
Oct 22 21:45:05 kefk kernel: Call Trace:
Oct 22 21:45:05 kefk kernel:  [<c01f2087>] kobject_del+0x14/0x1c
Oct 22 21:45:05 kefk kernel:  [<c01f2097>] kobject_unregister+0x8/0x10
Oct 22 21:45:05 kefk kernel:  [<c01849fc>] del_gendisk+0x1d/0xd5
Oct 22 21:45:05 kefk kernel:  [<f8c48ff1>] ub_disconnect+0x11e/0x171 [ub]
Oct 22 21:45:05 kefk kernel:  [<c0298f95>] usb_unbind_interface+0x5e/0x60
Oct 22 21:45:05 kefk kernel:  [<c0243431>] device_release_driver+0x56/0x58
Oct 22 21:45:05 kefk kernel:  [<c0243637>] bus_remove_device+0x53/0x90
Oct 22 21:45:05 kefk kernel:  [<c0242752>] device_del+0x54/0x91
Oct 22 21:45:05 kefk kernel:  [<c02a0ac3>] usb_disable_device+0xda/0x147
Oct 22 21:45:05 kefk kernel:  [<c029b7ab>] usb_disconnect+0xab/0x198
Oct 22 21:45:05 kefk kernel:  [<c029ca61>] hub_port_connect_change+0x2ce/0x47b
Oct 22 21:45:05 kefk kernel:  [<c029cee2>] hub_events+0x2d4/0x4ac
Oct 22 21:45:05 kefk kernel:  [<c029d0ef>] hub_thread+0x35/0x10e
Oct 22 21:45:05 kefk kernel:  [<c0115155>] finish_task_switch+0x3b/0x87
Oct 22 21:45:05 kefk kernel:  [<c012d9ad>] autoremove_wake_function+0x0/0x43
Oct 22 21:45:05 kefk kernel:  [<c0103ca6>] ret_from_fork+0x6/0x14
Oct 22 21:45:05 kefk kernel:  [<c012d9ad>] autoremove_wake_function+0x0/0x43
Oct 22 21:45:05 kefk kernel:  [<c029d0ba>] hub_thread+0x0/0x10e
Oct 22 21:45:05 kefk kernel:  [<c0102025>] kernel_thread_helper+0x5/0xb
Oct 22 21:45:05 kefk kernel: Code: 02 4c 32 c0 e9 4d ff ff ff e9 23 ff ff ff 
55 57 56 53 83 ec 04 8b 78 30 85 ff 74 0d 8b 07 85 c0 0f 84 ca 00 00 00 f0 ff 
07 85 ff <8b> 57 50 0f 84 b4 00 00 00 8b 47 10 8d 48 78 f0 ff 48 78 0f 88


After this, usb stack is unable to detect other usb devices insertions.

system: P IV 2.8 HT, smp/t+preempt, i875p (abit ic7g) 1Gb ram.
flash key: usb 2.0 flash drive, 512 MB

I can provide more details/testing if needed, config.gz attached.



-- 
Fabio Coatti       http://members.ferrara.linux.it/cova     
Ferrara Linux Users Group           http://ferrara.linux.it
GnuPG fp:9765 A5B6 6843 17BC A646  BE8C FA56 373A 5374 C703
Old SysOps never die... they simply forget their password.