Most recent kernel where this bug did not occur: Dunno
Distribution: Debian testing
Hardware Environment: Dual P3 1 GB RAM, Broadcom OSB4/CSB5 OHCI usb chipset,
radeon 9200 SE graphics card, IDE disk
Software Environment: Kopete 3.5 (kde 3.5) or xawtv
Problem Description: I get an oops (not hang) if I plug/unplug the camera
quickly while the program is trying to initializate/use the camera

Steps to reproduce: 
1) Plug in the camera (udev loads the modules)
2) Run xawtv or go to the kopete's 3.5 webcam configuration panel
3) Unplug & plug the camera like mad until you get an oops.


I've two different oopses. The first one was taken in 2.6.15-rc5 and the
following one the linus' git tree from two days ago or so.

Unable to handle kernel NULL pointer dereference at virtual address 0000000c
 printing eip:
c019b162
*pde = 00000000
Oops: 0000 [#1]
PREEMPT SMP
Modules linked in: ovcamchip w9968cf videodev i2c_core ipt_REJECT radeon drm
thermal fan button processor ac battery ipt_MASQUERADE iptable_nat ip_nat
ip_conntrack iptable_filter ip_tables usbhid snd_ca0106 snd_rawmidi
snd_seq_device snd_ac97_codec snd_pcm_oss snd_mixer_oss snd_pcm parport_pc
floppy snd_timer parport ohci_hcd snd pcspkr usbcore e100 soundcore snd_ac97_bus
snd_page_alloc
CPU:    0
EIP:    0060:[<c019b162>]    Not tainted VLI
EFLAGS: 00010246   (2.6.15-rc5)
EIP is at sysfs_hash_and_remove+0x22/0xef
eax: f4789bc8   ebx: f76338a8   ecx: c19b2d40   edx: c533de44
esi: 00000000   edi: f6a79600   ebp: f8962f40   esp: ec721f04
ds: 007b   es: 007b   ss: 0068
Process kopete (pid: 21843, threadinfo=ec721000 task=c91bfab0)
Stack: f6a79600 f4789bc8 e9ce0788 f76338a8 f76338a0 f6a79600 f8962f40 c022e426
       00000000 f8962fbc f76338a0 f8870f00 f7094830 f387ed08 c022e488 f4bc0000
       f89617c2 ec721f54 f89c1deb f89c8abc f8870f00 f4bc00bc 00000000 f4bc0000
Call Trace:
 [<c022e426>] class_device_del+0xa6/0x100
 [<c022e488>] class_device_unregister+0x8/0x10
 [<f89617c2>] video_unregister_device+0x32/0x4d [videodev]
 [<f89c1deb>] w9968cf_release_resources+0x3b/0xf0 [w9968cf]
 [<f89c24d0>] w9968cf_release+0x40/0x100 [w9968cf]
 [<c0163a01>] __fput+0x91/0x180
 [<c0162097>] filp_close+0x47/0x90
 [<c0103061>] syscall_call+0x7/0xb
Code: 26 00 8d bc 27 00 00 00 00 55 57 56 53 83 ec 0c 89 44 24 04 89 14 24 8b 50
10 8b 70 58 85 d2 74 73 f0 ff 4a 78 0f 88 cd 00 00 00 <8b> 46 0c 8d 68 fc 8b 4d
04 0f 18 01 90 83 c6 0c 89 c3 39 f0 89
 <6>usb 1-1: OV7620 image sensor initialized
usb 1-1: USB disconnect, address 5
usb 1-1: Disconnecting Creative Labs Video Blaster WebCam Go Plus...







usb 1-1: Device not present
usb 1-1: Device not present
usb 1-1: V4L device deregistered: /dev/video0
Unable to handle kernel NULL pointer dereference at virtual address 0000000c
 printing eip:
c0179236
*pde = 00000000
Oops: 0000 [#1]
PREEMPT SMP
Modules linked in: ovcamchip w9968cf compat_ioctl32 videodev i2c_core ipt_REJECT
radeon drm thermal fan button processor ac battery ipt_MASQUERADE iptable_nat
ip_nat ip_conntrack iptable_filter ip_tables usbhid snd_ca0106 snd_rawmidi
snd_seq_device snd_ac97_codec snd_pcm_oss snd_mixer_oss snd_pcm snd_timer snd
soundcore parport_pc snd_ac97_bus parport snd_page_alloc ide_cd pcspkr e100
floppy ohci_hcd usbcore cdrom
CPU:    0
EIP:    0060:[<c0179236>]    Not tainted VLI
EFLAGS: 00010246   (2.6.15)
EIP is at sysfs_hash_and_remove+0x32/0xf0
eax: 00000000   ebx: f6578ea0   ecx: c1955d40   edx: d9afa790
esi: f66dbea0   edi: f8959d20   ebp: f8959d9c   esp: e57abf38
ds: 007b   es: 007b   ss: 0068
Process xawtv (pid: 20014, threadinfo=e57ab000 task=f7caaa70)
Stack: f66dbea0 def2e910 00000000 f6578ea0 f66dbea0 f8959d20 f8959d9c c01f0458
       00000000 f6578ea0 f8854bdd f36596b4 e72964d0 c01f04b0 e9721000 f89585e4
       f89c5513 e9721000 e97218b0 f89c5a4d e7296534 f65cf320 c014dd8f c195a120
Call Trace:
 [<c01f0458>] class_device_del+0x88/0xd8
 [<c01f04b0>] class_device_unregister+0x8/0x10
 [<f89585e4>] video_unregister_device+0x3c/0x4a [videodev]
 [<f89c5513>] w9968cf_release_resources+0x69/0xc6 [w9968cf]
 [<f89c5a4d>] w9968cf_release+0x3d/0xd3 [w9968cf]
 [<c014dd8f>] __fput+0x8b/0x137
 [<c014c956>] filp_close+0x4e/0x54
 [<c01026e7>] sysenter_past_esp+0x54/0x75
Code: 89 44 24 04 89 14 24 8b 40 58 89 44 24 08 8b 44 24 04 8b 50 10 85 d2 0f 84
c4 00 00 00 f0 ff 4a 78 0f 88 c2 00 00 00 8b 44 24 08 <8b> 68 0c e9 85 00 00 00
83 7d 14 00 74 7c 89 e8 e8 e7 fe ff ff
 <6>usb 1-1: OV7620 image sensor initialized
usb 1-1: USB disconnect, address 69
usb 1-1: Disconnecting Creative Labs Video Blaster WebCam Go Plus...