usb unbind/bind => WARNING at fs/sysfs/dir.c [Was: 2.6.25-rc8-mm1]

[Jiri Slaby]

On 04/02/2008 06:32 AM, Andrew Morton wrote:
> ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.25-rc8/2.6.25-rc8-mm1/

After
$ echo -n 4-1.2 >/sys/bus/usb/drivers/usb/unbind
$ echo -n 4-1.2 >/sys/bus/usb/drivers/usb/bind

I have this in logs:

sysfs: duplicate filename 'usbdev4.12_ep81' can not be created
------------[ cut here ]------------
WARNING: at /home/l/latest/xxx/fs/sysfs/dir.c:425 sysfs_add_one+0x99/0xc0()
Modules linked in: usbhid hid nls_cp437 vfat fat usb_storage tun bitrev ipv6 
arc4 ecb crypto_blkcipher cryptomgr crypto_algapi ath5k mac80211 sr_mod crc32 
ohci1394 rtc_cmos cfg80211 ieee1394 floppy rtc_core ehci_hcd rtc_lib ff_memless 
cdrom [last unloaded: hid]
Pid: 539, comm: bash Tainted: G        W 2.6.25-rc8-mm1_64 #395

Call Trace:
 [<ffffffff8022f07f>] warn_on_slowpath+0x5f/0x80
 [<ffffffff80230197>] ? printk+0x67/0x70
 [<ffffffff802d9bd0>] ? sysfs_ilookup_test+0x0/0x20
 [<ffffffff802a12e8>] ? ifind+0x58/0xc0
 [<ffffffff802d9bd0>] ? sysfs_ilookup_test+0x0/0x20
 [<ffffffff802d9f49>] sysfs_add_one+0x99/0xc0
 [<ffffffff802daf68>] sysfs_create_link+0xa8/0x130
 [<ffffffff8038ebda>] device_add+0x2aa/0x4d0
 [<ffffffff80310c26>] ? kobject_init+0x36/0x80
 [<ffffffff8038ee19>] device_register+0x19/0x20
 [<ffffffff803dbbec>] usb_create_ep_files+0x19c/0x320
 [<ffffffff803dadb3>] usb_create_sysfs_intf_files+0xd3/0x100
 [<ffffffff803d630c>] usb_set_configuration+0x3ac/0x5f0
 [<ffffffff803df81a>] generic_probe+0x7a/0xb0
 [<ffffffff803d83fa>] usb_probe_device+0x3a/0x40
 [<ffffffff80390ceb>] driver_probe_device+0x9b/0x1a0
 [<ffffffff803901b3>] driver_bind+0xb3/0x100
 [<ffffffff8038f8a7>] drv_attr_store+0x27/0x30
 [<ffffffff802d94ab>] sysfs_write_file+0xeb/0x140
 [<ffffffff8028cc57>] vfs_write+0xc7/0x170
 [<ffffffff8028d2f0>] sys_write+0x50/0x90
 [<ffffffff8020b5eb>] system_call_after_swapgs+0x7b/0x80

---[ end trace 6ee6d593d4e510b4 ]---




I think, this is a 2.6.25-rc5-mm1 regression, there
while :; do
  echo -n 4-1.2 >/sys/bus/usb/drivers/usb/unbind
  echo -n 4-1.2 >/sys/bus/usb/drivers/usb/bind
  usleep 10000
done
went just fine for about 2000 times. Also real disconnect/connect works just 
fine (on disconnect the link disappears). Do you need kobject debug output?




The dir looks like:
...
usbdev4.10_ep83 -> 
../../devices/pci0000:00/0000:00:1d.0/usb4/4-1/4-1.3/4-1.3:1.0/usb_endpoint/usbdev4.10_ep83
usbdev4.12_ep81 -> 
../../devices/pci0000:00/0000:00:1d.0/usb4/4-1/4-1.2/4-1.2:1.0/usb_endpoint/usbdev4.12_ep81

^^^^
this is the unbound, the link is broken, there is no such device even after 
binding it back.

usbdev4.1_ep00 -> 
../../devices/pci0000:00/0000:00:1d.0/usb4/usb_endpoint/usbdev4.1_ep00
usbdev4.1_ep81 -> 
../../devices/pci0000:00/0000:00:1d.0/usb4/4-0:1.0/usb_endpoint/usbdev4.1_ep81
usbdev4.5_ep00 -> 
../../devices/pci0000:00/0000:00:1d.0/usb4/4-1/usb_endpoint/usbdev4.5_ep00
...


The device is:
Bus 004 Device 012: ID 045e:00f0 Microsoft Corp.
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass            0 (Defined at Interface level)
  bDeviceSubClass         0
  bDeviceProtocol         0
  bMaxPacketSize0         8
  idVendor           0x045e Microsoft Corp.
  idProduct          0x00f0
  bcdDevice            1.01
  iManufacturer           1 Microsoft Corporation
  iProduct                2 Microsoft ï Laser Mouse 6000
  iSerial                 0
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength           34
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0
    bmAttributes         0xa0
      (Bus Powered)
      Remote Wakeup
    MaxPower              100mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           1
      bInterfaceClass         3 Human Interface Devices
      bInterfaceSubClass      1 Boot Interface Subclass
      bInterfaceProtocol      2 Mouse
      iInterface              0
        HID Device Descriptor:
          bLength                 9
          bDescriptorType        33
          bcdHID               1.11
          bCountryCode           33 US
          bNumDescriptors         1
          bDescriptorType        34 Report
          wDescriptorLength      59
         Report Descriptors:
           ** UNAVAILABLE **
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0004  1x 4 bytes
        bInterval              10
Device Status:     0x0000
  (Bus Powered)
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/