fs_enet segfaults when adding network interface to bridge

[Laurent Pinchart]

Hi everybody,

I ran into a segfault in the fs_enet driver when adding the network interface 
to an ethernet bridge. This only happens when the interface is down.

----- Kernel version -----
Linux tbox-cp11 2.6.17-rc3-g7f02f290-dirty #549 Tue May 30 13:25:37 CEST 2006 
ppc unknown
(from main linux-2.6 git repository)
----- End of kernel version -----

----- Oops report -----
Oops: kernel access of bad area, sig: 11 [#1]
NIP: C0109884 LR: C010D420 CTR: 00000000
REGS: c027d7f0 TRAP: 0300   Tainted: P       (2.6.17-rc3-g7f02f290-dirty)
MSR: 00009032 <EE,ME,IR,DR>  CR: 24000222  XER: 00000000
DAR: 00000140, DSISR: 20000000
TASK = c0851090[42] 'brctl' THREAD: c027c000
GPR00: C010D414 C027D8A0 C0851090 00000000 C027D8D0 FFFFFFFF F00000A0 EFFFFFFF
GPR08: C026E380 C0210000 00000000 C0230000 C0210000 1001D150 00FFE000 00000001
GPR16: FFFFFFFF 00000000 007FFF00 7FDD0AC0 00000000 10072C94 7FDD0AD8 10072CA4
GPR24: 00000000 10000A48 00000000 C027D8D0 C027D8D0 C08A1A60 C027DC50 C08A1800
NIP [C0109884] phy_ethtool_gset+0x0/0x48
LR [C010D420] fs_get_settings+0x34/0x48
Call Trace:
[C027D8A0] [C010D414] fs_get_settings+0x28/0x48 (unreliable)
[C027D8C0] [C013DDC0] dev_ethtool+0x9bc/0x13c8
[C027DC40] [C018CBC0] port_cost+0x58/0x108
[C027DCB0] [C018D3E8] br_add_if+0x174/0x2f4
[C027DCE0] [C018D9AC] add_del_if+0x94/0x98
[C027DD00] [C018DD68] br_dev_ioctl+0x70/0xae4
[C027DE00] [C013B42C] dev_ifsioc+0x17c/0x404
[C027DE20] [C013BA4C] dev_ioctl+0x398/0x4e8
[C027DEB0] [C012EEFC] sock_ioctl+0x154/0x220
[C027DEE0] [C0067164] do_ioctl+0x88/0x9c
[C027DEF0] [C0067230] vfs_ioctl+0xb8/0x3f0
[C027DF10] [C00675A8] sys_ioctl+0x40/0x74
[C027DF40] [C00040E0] ret_from_syscall+0x0/0x38
Instruction dump:
7c0803a6 4e800020 2f800000 409eff78 4bffffb8 8804000e 2b800001 40bdff70
3860ffea 4bffffd4 61200040 4bffff84 <81230140> 91240004 80030144 90040008
----- End of oops report -----

----- Source lines -----
[C0109884] phy_ethtool_gset+0x0/0x48 (drivers/net/phy/phy.c:290)
[C010D414] fs_get_settings+0x28/0x48 (drivers/net/fs_enet/fs_enet-main.c:885)
[C013DDC0] dev_ethtool+0x9bc/0x13c8 (net/core/ethtool.c:122)
[C018CBC0] port_cost+0x58/0x108 (net/bridge/br_if.c:54)
----- End of source lines -----

phy_ethtool_gset segfaults when trying to access phydev->supported because 
phydev is NULL.

As I'm not familiar with the fs_enet driver, I'm looking for advices regarding 
what to fix and how to fix it.

Laurent Pinchart