Hi, Shawn,

On Wed, Feb 23, 2011 at 3:27 PM, Shawn Guo <email address hidden> wrote:
> Yes, Jason.  I noticed that commit.  But when I rolled back the code to
> the version just before that commit.  I did not see the trace warning
> show up again.  So I'm not sure it's the commit that fixed the problem.

If you rolled back to the commit: fac70d51914674ce8ae742ed73441ddb4770ad20
which is one commit earlier than
6fcc040f02d281c7e9563127358a77ce2bbfe284(net: allow FEC driver to use
fixed PHY support)

you will see the error, I have tested and can confirm it.

....
>
> --
> You received this bug notification because you are a member of Linaro
> Kernel Working Group, which is the registrant for Linaro Linux.
> https://bugs.launchpad.net/bugs/655641
>
> Title:
>  mii_bus fails to register on imx51
>
> Status in Linaro Linux:
>  Invalid
>
> Bug description:
>  The mii_bus fails to register on imx51 and gives the following trace info.  Clean of CONFIG_FIXED_PHY can remove the error.
>
>  Fixed MDIO Bus: probed
>  FEC Ethernet Driver
>  ------------[ cut here ]------------
>  WARNING: at /build/buildd/linux-linaro-2.6.35/fs/sysfs/dir.c:451 sysfs_add_one+0
>  x6c/0x8c()
>  sysfs: cannot create duplicate filename '/class/mdio_bus/0'
>  Modules linked in:
>  Backtrace:
>  [<c0034540>] (dump_backtrace+0x0/0xf8) from [<c0308c68>] (dump_stack+0x18/0x1c)
>   r6:c03c0cef r5:000001c3 r4:df837d18 r3:f357b213
>  [<c0308c50>] (dump_stack+0x0/0x1c) from [<c0043d84>] (warn_slowpath_common+0x54/
>  0x6c)
>  [<c0043d30>] (warn_slowpath_common+0x0/0x6c) from [<c0043e40>] (warn_slowpath_fm
>  t+0x38/0x40)
>   r8:00000001 r7:df837d68 r6:df3dd090 r5:df811000 r4:ffffffef
>  r3:00000009
>  [<c0043e08>] (warn_slowpath_fmt+0x0/0x40) from [<c00ef150>] (sysfs_add_one+0x6c/
>  0x8c)
>   r3:df811000 r2:c03c0d20
>  [<c00ef0e4>] (sysfs_add_one+0x0/0x8c) from [<c00f00d0>] (sysfs_do_create_link+0x
>  fc/0x1cc)
>   r7:df85aa20 r6:df3dd000 r5:df3d1648 r4:df3dd090
>  [<c00effd4>] (sysfs_do_create_link+0x0/0x1cc) from [<c00f01cc>] (sysfs_create_li
>  nk+0x14/0x18)
>  [<c00f01b8>] (sysfs_create_link+0x0/0x18) from [<c0206b6c>] (device_add_class_sy
>  mlinks+0x5c/0xd8)
>  [<c0206b10>] (device_add_class_symlinks+0x0/0xd8) from [<c02072c0>] (device_add+
>  0x110/0x2dc)
>   r6:c041bda8 r5:00000000 r4:df3d1640 r3:00000000
>  [<c02071b0>] (device_add+0x0/0x2dc) from [<c02074a8>] (device_register+0x1c/0x20
>  )
>   r7:df3d1604 r6:df3d1640 r5:df3fc340 r4:df3d1640
>  [<c020748c>] (device_register+0x0/0x20) from [<c0238d00>] (mdiobus_register+0x90
>  /0x178)
>   r4:df3d1600 r3:00000000
>  [<c0238c70>] (mdiobus_register+0x0/0x178) from [<c023c51c>] (fec_enet_mii_init+0
>  x120/0x164)
>   r8:c041bda0 r7:00000080 r6:df3d1600 r5:df3fc340 r4:df3fc000
>  r3:df3d3ba0
>  [<c023c3fc>] (fec_enet_mii_init+0x0/0x164) from [<c0308494>] (fec_probe+0x170/0x
>  1f4)
>   r8:c041bda8 r7:df3fc340 r6:00000001 r5:c041bda0 r4:df3fc000
>  r3:ffc000f8
>  [<c0308324>] (fec_probe+0x0/0x1f4) from [<c020a840>] (platform_drv_probe+0x1c/0x
>  20)
>  [<c020a824>] (platform_drv_probe+0x0/0x20) from [<c0209754>] (really_probe+0xa0/
>  0x150)
>  [<c02096b4>] (really_probe+0x0/0x150) from [<c0209854>] (driver_probe_device+0x5
>  0/0x68)
>   r7:00000000 r6:c043e5f4 r5:c043e5f4 r4:c041bda8
>  [<c0209804>] (driver_probe_device+0x0/0x68) from [<c02098d4>] (__driver_attach+0
>  x68/0x8c)
>   r5:c041bddc r4:c041bda8
>  [<c020986c>] (__driver_attach+0x0/0x8c) from [<c0208ef8>] (bus_for_each_dev+0x54
>  /0x84)
>   r6:00000000 r5:c020986c r4:c043e5f4 r3:00000000
>  [<c0208ea4>] (bus_for_each_dev+0x0/0x84) from [<c02095c8>] (driver_attach+0x20/0
>  x28)
>   r6:c04369f8 r5:df3d3ae0 r4:c043e5f4
>  [<c02095a8>] (driver_attach+0x0/0x28) from [<c0208814>] (bus_add_driver+0xa4/0x1
>  9c)
>  [<c0208770>] (bus_add_driver+0x0/0x19c) from [<c0209c9c>] (driver_register+0xb0/
>  0xe4)
>   r7:00000013 r6:00000000 r5:c00086ec r4:c043e5f4
>  [<c0209bec>] (driver_register+0x0/0xe4) from [<c020ad44>] (platform_driver_regis
>  ter+0x4c/0x60)
>   r5:c00086ec r4:c001fa4c
>  [<c020acf8>] (platform_driver_register+0x0/0x60) from [<c001fa68>] (fec_enet_mod
>  ule_init+0x1c/0x28)
>  [<c001fa4c>] (fec_enet_module_init+0x0/0x28) from [<c002b340>] (do_one_initcall+
>  0x60/0x1c4)
>  [<c002b2e0>] (do_one_initcall+0x0/0x1c4) from [<c00086a4>] (do_initcalls+0x1c/0x
>  38)
>   r9:00000000 r8:00000000 r7:00000013 r6:c0047324 r5:c00086ec
>  r4:c0026840
>  [<c0008688>] (do_initcalls+0x0/0x38) from [<c00086e8>] (do_basic_setup+0x28/0x2c
>  )
>   r4:00000000 r3:00000000
>  [<c00086c0>] (do_basic_setup+0x0/0x2c) from [<c0008738>] (kernel_init+0x4c/0xec)
>  [<c00086ec>] (kernel_init+0x0/0xec) from [<c0047324>] (do_exit+0x0/0x258)
>   r4:00000000 r3:00000000
>  ---[ end trace 1c431abc57d885c7 ]---
>  mii_bus 0 failed to register
>