On Tue, 29 May 2012, Johan Hovold wrote: > This looks like it could be related to the following oops I keep > triggering on driver reload (using usb-3.5-rc1) but haven't had time to > investigate further yet: > > [11811.646396] drivers/usb/serial/usb-serial.c: get_free_serial 1 > [11811.646443] drivers/usb/serial/usb-serial.c: get_free_serial - minor base = 0 > [11811.646460] drivers/usb/serial/usb-serial.c: usb_serial_probe - registering ttyUSB0 > [11811.646766] usb 6-1: pl2303 converter now attached to ttyUSB0 > [11812.264197] USB Serial deregistering driver FTDI USB Serial Device > [11812.264865] usbcore: deregistering interface driver ftdi_sio > [11812.282180] USB Serial deregistering driver pl2303 > [11812.283141] pl2303 ttyUSB0: pl2303 converter now disconnected from ttyUSB0 > [11812.283272] usbcore: deregistering interface driver pl2303 > [11812.301056] USB Serial deregistering driver generic > [11812.301186] usbcore: deregistering interface driver usbserial_generic > [11812.301259] drivers/usb/serial/usb-serial.c: usb_serial_disconnect > [11812.301823] BUG: unable to handle kernel paging request at f8e7438c > [11812.301845] IP: [<f8e38445>] usb_serial_disconnect+0xb5/0x100 [usbserial] > [11812.301871] *pde = 357ef067 *pte = 00000000 > [11812.301957] Oops: 0000 [#1] PREEMPT SMP > [11812.301983] Modules linked in: usbserial(-) [last unloaded: pl2303] > [11812.302008] > [11812.302019] Pid: 1323, comm: modprobe Tainted: G W 3.4.0-rc7+ #101 Dell Inc. Vostro 1520/0T816J > [11812.302115] EIP: 0060:[<f8e38445>] EFLAGS: 00010246 CPU: 1 > [11812.302130] EIP is at usb_serial_disconnect+0xb5/0x100 [usbserial] > [11812.302141] EAX: f508a180 EBX: f508a180 ECX: 00000000 EDX: f8e74300 > [11812.302151] ESI: f5050800 EDI: 00000001 EBP: f5141e78 ESP: f5141e58 > [11812.302160] DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 > [11812.302170] CR0: 8005003b CR2: f8e7438c CR3: 34848000 CR4: 000007d0 > [11812.302180] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 > [11812.302189] DR6: ffff0ff0 DR7: 00000400 > [11812.302199] Process modprobe (pid: 1323, ti=f5140000 task=f61e2bc0 task.ti=f5140000) > [11812.302209] Stack: > [11812.302216] f8e3be0f f8e3b29c f8e3ae00 00000000 f513641c f5136400 f513641c f507a540 > [11812.302325] f5141e98 c133d2c1 00000000 00000000 f509c400 f513641c f507a590 f5136450 > [11812.302372] f5141ea8 c12f0344 f513641c f507a590 f5141ebc c12f0c67 00000000 f507a590 > [11812.302419] Call Trace: > [11812.302439] [<c133d2c1>] usb_unbind_interface+0x51/0x190 > [11812.302456] [<c12f0344>] __device_release_driver+0x64/0xb0 > [11812.302469] [<c12f0c67>] driver_detach+0x97/0xa0 > [11812.302483] [<c12f001c>] bus_remove_driver+0x6c/0xe0 > [11812.302500] [<c145938d>] ? __mutex_unlock_slowpath+0xcd/0x140 > [11812.302514] [<c12f0ff9>] driver_unregister+0x49/0x80 > [11812.302528] [<c1457df6>] ? printk+0x1d/0x1f > [11812.302540] [<c133c50d>] usb_deregister+0x5d/0xb0 > [11812.302557] [<f8e37c55>] ? usb_serial_deregister+0x45/0x50 [usbserial] > [11812.302575] [<f8e37c8d>] usb_serial_deregister_drivers+0x2d/0x40 [usbserial] > [11812.302593] [<f8e3a6e2>] usb_serial_generic_deregister+0x12/0x20 [usbserial] > [11812.302611] [<f8e3acf0>] usb_serial_exit+0x8/0x32 [usbserial] > [11812.302716] [<c1080b48>] sys_delete_module+0x158/0x260 > [11812.302730] [<c110594e>] ? mntput+0x1e/0x30 > [11812.302746] [<c145c3c3>] ? sysenter_exit+0xf/0x18 > [11812.302746] [<c107777c>] ? trace_hardirqs_on_caller+0xec/0x170 > [11812.302746] [<c145c390>] sysenter_do_call+0x12/0x36 > [11812.302746] Code: 24 02 00 00 e8 dd f3 20 c8 f6 86 74 02 00 00 02 74 b4 8d 86 4c 02 00 00 47 e8 78 55 4b c8 0f b6 43 0e 39 f8 7f a9 8b 53 04 89 d8 <ff> 92 8c 00 00 00 89 d8 e8 0e ff ff ff 8b 45 f0 c7 44 24 04 2f > [11812.302746] EIP: [<f8e38445>] usb_serial_disconnect+0xb5/0x100 [usbserial] SS:ESP 0068:f5141e58 > [11812.302746] CR2: 00000000f8e7438c This is the serial->type->disconnect(serial); call near the end of usb_serial_disconnect(). Evidently the crash occurs because pl2303_device doesn't have a disconnect method. It would help if the serial.h file explained clearly which methods are optional and which are obligatory. At any rate, the bug can be fixed by testing whether serial->type->disconnect is non-NULL before calling it. This does not appear to be related to Bjørn's problem. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
