On Thu, Mar 15, 2012 at 10:02:34AM +0800, Ken Huang wrote: > hi, > > Prevousely i was working on an sms related program using a ftdichip modem in > 2.6.30-gentoor8 linux with ftdi_sio driver v1.4.3. > But i was running into a weird situation: > when OS starts up, my program will try to open /dev/ttyUSB0 infinitely > without sleep until it succeeds(due to be not considered properly when > coding), and then i plugin my USB serial modem, a bug message will > show up immediately with dmesg, and if i unplug modem, the system will > have no response. Then my program may be killed or be in state D. > > the BUG message copied from dmesg: > > [ 43.769794] BUG: unable to handle kernel NULL pointer dereference > at 00000074 > [ 43.775687] IP: [<405829ba>] _spin_lock_irqsave+0x8/0x1a > [ 43.775687] *pdpt = 000000009ad51001 <6>usb 2-2: Detected FT232BM > [ 43.785760] usb 2-2: FTDI USB Serial Device converter now attached > to ttyUSB0 > [ 43.785840] drivers/usb/core/inode.c: creating file '002' > [ 43.785686] *pde = 0000000000000000 > [ 43.785686] Oops: 0002 [#1] SMP > [ 43.785686] last sysfs file: > [ 43.785686] Modules linked in: ixgbe igb dca e1000e e1000 > [ 43.785686] > [ 43.785686] Pid: 1059, comm: smssp.orig Not tainted (2.6.30-gentoo- > r8 #24) AM5400B > [ 43.785686] EIP: 0060:[<405829ba>] EFLAGS: 00010046 CPU: 1 > [ 43.785686] EIP is at _spin_lock_irqsave+0x8/0x1a > [ 43.785686] EAX: 00000074 EBX: 00000074 ECX: 00000246 EDX: 00000100 > [ 43.785686] ESI: dade8400 EDI: 00000000 EBP: d903ba00 ESP: da43be28 > [ 43.785686] DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 > [ 43.785686] Process smssp.orig (pid: 1059, ti=da43a000 > task=dad6f710 task.ti=da43a000) > [ 43.785686] Stack: > [ 43.785686] 4047d5c8 da5f3000 4045bbb5 4073d460 d903ba00 d9001340 > dade8400 404799fd > [ 43.785686] d88bfb40 d9001378 d903bad0 d903ba58 d903ba04 da652300 > dade8400 d88bfb40 > [ 43.785686] dade8400 4035d144 da8e48a8 00000000 00000902 00000100 > 0bc00000 00000000 > [ 43.785686] Call Trace: > [ 43.785686] [<4047d5c8>] ? ftdi_open+0x42/0x1a1 > [ 43.785686] [<4045bbb5>] ? usb_autopm_do_interface+0x9a/0xa1 > [ 43.785686] [<404799fd>] ? serial_open+0x112/0x189 > [ 43.785686] [<4035d144>] ? tty_open+0x27b/0x3a9 > [ 43.785686] [<40293524>] ? chrdev_open+0x128/0x152 > [ 43.785686] [<402a198c>] ? mntput_no_expire+0x12/0xe0 > [ 43.785686] [<402933fc>] ? chrdev_open+0x0/0x152 > [ 43.785686] [<4028f5dd>] ? __dentry_open+0x113/0x1e9 > [ 43.785686] [<40290413>] ? nameidata_to_filp+0x29/0x3c > [ 43.785686] [<40299ac4>] ? do_filp_open+0x3ab/0x689 > [ 43.785686] [<4025d5bb>] ? __rcu_process_callbacks+0x57/0x159 > [ 43.785686] [<40236d6a>] ? autoremove_wake_function+0x0/0x2d > [ 43.785686] [<402a05ff>] ? alloc_fd+0x5e/0xd0 > [ 43.785686] [<4028f3ea>] ? do_sys_open+0x44/0xb4 > [ 43.785686] [<4028f49e>] ? sys_open+0x1e/0x23 > [ 43.785686] [<40202964>] ? sysenter_do_call+0x12/0x22 > [ 43.785686] Code: 74 05 e8 3e fe ff ff c3 fa f0 83 28 01 79 05 e8 > 4d fe ff ff c3 f0 81 00 00 00 00 01 fb c3 f0 ff 00 fb c3 9c 59 fa ba > 00 01 00 00 <f0> 66 0f c1 10 38 f2 74 06 f3 90 8a 10 eb f6 89 c8 c3 9c > 5a fa > [ 43.785686] EIP: [<405829ba>] _spin_lock_irqsave+0x8/0x1a SS:ESP > 0068:da43be28 > [ 43.785686] CR2: 0000000000000074 > [ 43.785686] ---[ end trace b68e6189f2a3d267 ]--- > [ 45.882827] hub 1-0:1.0: hub_suspend > [ 45.886552] usb usb1: bus auto-suspend > [ 45.890434] ehci_hcd 0000:00:1d.7: suspend root hub The oops above is from 2.6.30 -- can you reproduce this on 3.2.11 and attach the corresponding oops message? [...] > reproducing procedure: > 1.insmod usbserial.ko ftdi_sio.ko > 2.#./usb.exe to run my test program > 3.plug USB modem in and the dmesg about ftdi_sio stack info above > shows up Can you reproduce this if you enable debugging by loading the modules with the debug flag? modprobe usbserial debug=1 modprobe ftdi_sio debug=1 [...] > I've tried to compile newer kernel to check if it has similar > issue(bug info from dmesg), and > the follow is the tested buggy kernel: > 2.6.32.58 > 2.6.35.13 > 3.2.11 > all of them are downloaded from main page of kernel.org Please try the above with 3.2.11. Thanks, Johan -- 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
