On Mon, 17 Oct 2011, Tomas M. wrote: > im getting the following null pointer dereference from time to time when > releasing a usb camera. > > maybe this trace is of assistance...please reply to my mail since im not > subscribed. > I suspect this is happening in v4l2_device_unregister_subdev(). Adding Guennadi, Mauro, and linux-media. > BUG: unable to handle kernel NULL pointer dereference at 0000006c > IP: [<f90be6c2>] v4l2_device_release+0xa2/0xf0 [videodev] > *pde = 00000000 > Oops: 0000 [#1] PREEMPT SMP > Modules linked in: fuse arc4 rt73usb rt2x00usb rt2x00lib mac80211 cfg80211 > rfkill gspca_zc3xx gspca_main videodev joydev snd_hda_codec_si3054 sg 8139too > snd_hda_codec_realtek firewire_ohci firewire_core mmc_core snd_hda_intel > snd_hda_codec snd_hwdep snd_pcm snd_timer snd soundcore mii crc_itu_t > snd_page_alloc iTCO_wdt iTCO_vendor_support i2c_i801 evdev psmouse thermal > battery serio_raw ac cpufreq_ondemand acpi_cpufreq freq_table processor mperf > usbhid hid ext3 jbd mbcache sd_mod sr_mod cdrom pata_acpi uhci_hcd ata_piix > ehci_hcd libata scsi_mod usbcore [last unloaded: sdhci] > > Pid: 171, comm: khubd Not tainted 3.1.0-rc9 #66 Everex Systems, Inc. Everex > StepNote Series/Everex StepNote Series > EIP: 0060:[<f90be6c2>] EFLAGS: 00010292 CPU: 0 > EIP is at v4l2_device_release+0xa2/0xf0 [videodev] > EAX: 00000000 EBX: f5636004 ECX: 00000000 EDX: 00000000 > ESI: f5636000 EDI: 00000000 EBP: f563600c ESP: f5627e38 > DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 > Process khubd (pid: 171, ti=f5626000 task=f554dc00 task.ti=f5626000) > Stack: > ef000480 c1433780 f5474b00 c12343f8 f54e7e1c 00000000 c114737a f563600c > f5636028 c114605d f5636028 c1146020 f91512d4 00000000 c114737a f54e7e1c > f54e7e00 f81623f4 f56d4000 f54e7e1c f91512d4 f56d4064 00000001 c12373b7 > Call Trace: > [<c12343f8>] ? device_release+0x18/0x80 > [<c114737a>] ? kref_put+0x2a/0x60 > [<c114605d>] ? kobject_release+0x3d/0xa0 > [<c1146020>] ? kobject_del+0x30/0x30 > [<c114737a>] ? kref_put+0x2a/0x60 > [<f81623f4>] ? usb_unbind_interface+0x34/0x130 [usbcore] > [<c12373b7>] ? __device_release_driver+0x57/0xb0 > [<c123742d>] ? device_release_driver+0x1d/0x30 > [<c1236fc2>] ? bus_remove_device+0x72/0x90 > [<c12350bf>] ? device_del+0xdf/0x150 > [<f8160591>] ? usb_disable_device+0x81/0x180 [usbcore] > [<f8159b3b>] ? usb_disconnect+0x8b/0x110 [usbcore] > [<f815b76c>] ? hub_thread+0x97c/0x1180 [usbcore] > [<c102d80b>] ? pick_next_task_fair+0x8b/0xe0 > [<c1052600>] ? abort_exclusive_wait+0x90/0x90 > [<f815adf0>] ? usb_remote_wakeup+0x40/0x40 [usbcore] > [<c1052029>] ? kthread+0x69/0x70 > [<c1051fc0>] ? kthread_worker_fn+0x150/0x150 > [<c130d8be>] ? kernel_thread_helper+0x6/0xd > Code: 83 94 01 00 00 c7 83 60 01 00 00 00 00 00 00 0f b7 93 9c 01 00 00 c1 e0 > 05 f0 0f b3 90 c0 e7 0c f9 b8 20 e1 0c f9 e8 4e cf 24 c8 <8b> 57 6c 89 f0 85 > d2 74 25 ff 93 c8 01 00 00 85 ff 74 21 89 f8 > EIP: [<f90be6c2>] v4l2_device_release+0xa2/0xf0 [videodev] SS:ESP > 0068:f5627e38 > CR2: 000000000000006c > ---[ end trace 39522f0f1757c8f8 ]--- -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
