It's not at all clear how that could happen. Those pointers are located in static data in the HCD modules. It doesn't seem likely that the pointer was overwritten. The only other possibility I can think of is that the module was already unloaded. But that's not possible since you were holding a reference to a device on that bus.
It occurred on system shutdown - so I guess the module was unloaded. Maybe the bus reference counting is borked. I've sent Vince a patch that should produce some more info.
Actually, no need to be at system shutdown: in my case a simple
"/etc/init.d/hotplug stop" is enough to trigger the oops.
However, it doesn't happen every time, I had to try some times before I got another oops again. I enclose the logs with the additional debugging information in attachment.
Regards,
Vincent
kernel: ehci_hcd 0000:00:10.3: remove, state 1 kernel: usb usb1: USB disconnect, address 1 kernel: ehci_hcd 0000:00:10.3: USB bus 1 deregistered kernel: DEBUG kernel: Call Trace: kernel: [<e0afca9f>] hcd_pci_release+0x1f/0x70 [usbcore] kernel: [<c01bea5a>] unlink+0x7a/0x80 kernel: [<e0af857d>] usb_host_release+0x1d/0x20 [usbcore] kernel: [<c0205eb8>] class_dev_release+0x58/0x60 kernel: [<c01bee7b>] kobject_cleanup+0x7b/0x80 kernel: [<e0afd0ba>] usb_hcd_pci_remove+0x12a/0x180 [usbcore] kernel: [<c01c650b>] pci_device_remove+0x3b/0x40 kernel: [<c0205494>] device_release_driver+0x64/0x70 kernel: [<c02054c0>] driver_detach+0x20/0x30 kernel: [<c02056ed>] bus_remove_driver+0x3d/0x80 kernel: [<c0205b03>] driver_unregister+0x13/0x28 kernel: [<c01c66e6>] pci_unregister_driver+0x16/0x30 kernel: [<e0a19e6f>] cleanup+0xf/0x13 [ehci_hcd] kernel: [<c0136e43>] sys_delete_module+0x133/0x150 kernel: [<c014c124>] sys_munmap+0x44/0x70 kernel: [<c02a6f8e>] sysenter_past_esp+0x43/0x65 kernel: kernel: DEBUG: hcd->driver: e0a19ee0 kernel: DEBUG: hcd->driver->hcd_free: e0a166d0 kernel: uhci_hcd 0000:00:10.0: remove, state 1 kernel: usb usb2: USB disconnect, address 1 kernel: usb 2-1: USB disconnect, address 2 kernel: drivers/char/lirc/lirc_atiusb.c: USB Remote on #200 now disconnected kernel: usb 2-2: USB disconnect, address 3 kernel: uhci_hcd 0000:00:10.0: USB bus 2 deregistered kernel: uhci_hcd 0000:00:10.1: remove, state 1 kernel: usb usb3: USB disconnect, address 1 kernel: uhci_hcd 0000:00:10.1: USB bus 3 deregistered kernel: DEBUG kernel: Call Trace: kernel: [<e0afca9f>] hcd_pci_release+0x1f/0x70 [usbcore] kernel: [<c01bea5a>] unlink+0x7a/0x80 kernel: [<e0af857d>] usb_host_release+0x1d/0x20 [usbcore] kernel: [<c0205eb8>] class_dev_release+0x58/0x60 kernel: [<c01bee7b>] kobject_cleanup+0x7b/0x80 kernel: [<e0afd0ba>] usb_hcd_pci_remove+0x12a/0x180 [usbcore] kernel: [<c01c650b>] pci_device_remove+0x3b/0x40 kernel: [<c0205494>] device_release_driver+0x64/0x70 kernel: [<c02054c0>] driver_detach+0x20/0x30 kernel: [<c02056ed>] bus_remove_driver+0x3d/0x80 kernel: [<c0205b03>] driver_unregister+0x13/0x28 kernel: [<c01c66e6>] pci_unregister_driver+0x16/0x30 kernel: [<e0c8dd4f>] uhci_hcd_cleanup+0xf/0x59 [uhci_hcd] kernel: [<c0136e43>] sys_delete_module+0x133/0x150 kernel: [<c014c124>] sys_munmap+0x44/0x70 kernel: [<c02a6f8e>] sysenter_past_esp+0x43/0x65 kernel: kernel: DEBUG: hcd->driver: e0c8de40 kernel: DEBUG: hcd->driver->hcd_free: e0c8dce0 kernel: uhci_hcd 0000:00:10.2: remove, state 1 kernel: usb usb4: USB disconnect, address 1 kernel: uhci_hcd 0000:00:10.2: USB bus 4 deregistered kernel: DEBUG kernel: Call Trace: kernel: [<e0afca9f>] hcd_pci_release+0x1f/0x70 [usbcore] kernel: [<c01bea5a>] unlink+0x7a/0x80 kernel: [<e0af857d>] usb_host_release+0x1d/0x20 [usbcore] kernel: [<c0205eb8>] class_dev_release+0x58/0x60 kernel: [<c01bee7b>] kobject_cleanup+0x7b/0x80 kernel: [<e0afd0ba>] usb_hcd_pci_remove+0x12a/0x180 [usbcore] kernel: [<c01c650b>] pci_device_remove+0x3b/0x40 kernel: [<c0205494>] device_release_driver+0x64/0x70 kernel: [<c02054c0>] driver_detach+0x20/0x30 kernel: [<c02056ed>] bus_remove_driver+0x3d/0x80 kernel: [<c0205b03>] driver_unregister+0x13/0x28 kernel: [<c01c66e6>] pci_unregister_driver+0x16/0x30 kernel: [<e0c8dd4f>] uhci_hcd_cleanup+0xf/0x59 [uhci_hcd] kernel: [<c0136e43>] sys_delete_module+0x133/0x150 kernel: [<c014c124>] sys_munmap+0x44/0x70 kernel: [<c02a6f8e>] sysenter_past_esp+0x43/0x65 kernel: kernel: DEBUG: hcd->driver: e0c8de40 kernel: DEBUG: hcd->driver->hcd_free: e0c8dce0 kernel: DEBUG kernel: Call Trace: kernel: [<e0afca9f>] hcd_pci_release+0x1f/0x70 [usbcore] kernel: [<e0af857d>] usb_host_release+0x1d/0x20 [usbcore] kernel: [<c0205eb8>] class_dev_release+0x58/0x60 kernel: [<e0afb854>] usb_destroy_configuration+0xb4/0xf0 [usbcore] kernel: [<c01bee7b>] kobject_cleanup+0x7b/0x80 kernel: [<e0af48f6>] usb_release_dev+0x46/0x60 [usbcore] kernel: [<c0204160>] device_release+0x20/0x80 kernel: [<c01bee7b>] kobject_cleanup+0x7b/0x80 kernel: [<e0afdd39>] usbdev_release+0x79/0xb0 [usbcore] kernel: [<c01586c0>] __fput+0x100/0x120 kernel: [<c0156c99>] filp_close+0x59/0x90 kernel: [<c0156d31>] sys_close+0x61/0xa0 kernel: [<c02a6f8e>] sysenter_past_esp+0x43/0x65 kernel: kernel: DEBUG: hcd->driver: e0c8de40 kernel: Unable to handle kernel paging request at virtual address e0c8de68 kernel: printing eip: kernel: e0afcabf kernel: *pde = 1da4c067 kernel: *pte = 00000000 kernel: Oops: 0000 [#1] kernel: PREEMPT kernel: CPU: 0 kernel: EIP: 0060:[<e0afcabf>] Not tainted VLI kernel: EFLAGS: 00010286 kernel: EIP is at hcd_pci_release+0x3f/0x70 [usbcore] kernel: eax: e0c8de40 ebx: de529000 ecx: 00000001 edx: c02ef058 kernel: esi: c032265c edi: c0322680 ebp: decb6200 esp: da1cdee4 kernel: ds: 007b es: 007b ss: 0068 kernel: Process modem_run (pid: 2424, threadinfo=da1cc000 task=de73ad00) kernel: Stack: e0b02781 e0c8de40 de529050 e0af857d de529000 c0205eb8 de529048 e0afb854 kernel: c0322450 00000282 c01bee7b de529050 decb6200 c0322428 c0322440 e0af48f6 kernel: de529050 00000000 c0204160 decb62cc da1cc000 de6a4ec0 decf1398 decb62f4 kernel: Call Trace: kernel: [<e0af857d>] usb_host_release+0x1d/0x20 [usbcore] kernel: [<c0205eb8>] class_dev_release+0x58/0x60 kernel: [<e0afb854>] usb_destroy_configuration+0xb4/0xf0 [usbcore] kernel: [<c01bee7b>] kobject_cleanup+0x7b/0x80 kernel: [<e0af48f6>] usb_release_dev+0x46/0x60 [usbcore] kernel: [<c0204160>] device_release+0x20/0x80 kernel: [<c01bee7b>] kobject_cleanup+0x7b/0x80 kernel: [<e0afdd39>] usbdev_release+0x79/0xb0 [usbcore] kernel: [<c01586c0>] __fput+0x100/0x120 kernel: [<c0156c99>] filp_close+0x59/0x90 kernel: [<c0156d31>] sys_close+0x61/0xa0 kernel: [<c02a6f8e>] sysenter_past_esp+0x43/0x65 kernel: kernel: Code: e0 e8 46 63 62 df e8 91 e9 60 df 85 db 74 3b 8b 83 08 01 00 00 c7 04 24 81 27 b0 e0 89 44 24 04 e8 27 63 62 df 8b 83 08 01 00 00 <8b> 40 28 c7 04 24 c0 43 b0 e0 89 44 24 04 e8 0e 63 62 df 8b 83 kernel: <0>Fatal exception: panic in 5 seconds
