Latest working kernel version:  
Earliest failing kernel version: 2.6.25-gentoo-r4
Distribution: Gentoo Stage 1
Hardware Environment:
Software Environment:
Problem Description:

X dies and half-exits, not even leaving me at a terminal. I have to start X remotely and then exit it again to do anything.

------------[ cut here ]------------
kernel BUG at kernel/exit.c:78!
invalid opcode: 0000 [#1]
Modules linked in: i2c_dev w83627hf hwmon_vid nvidia(P) wm8775 cx25840 tuner tea5767 tda8290 tuner_xc2028 tda9887 tuner_simple mt20xx tea5761 ivtv cx2341x tveeprom i2c_nforce2

Pid: 8722, comm: sshd Tainted: P         (2.6.25-gentoo-r4 #3)
EIP: 0060:[<c011a6c3>] EFLAGS: 00010046 CPU: 0
EIP is at release_task+0x4d/0x243
EAX: f2f04b00 EBX: f3c64560 ECX: 00000000 EDX: 00000001
ESI: f2f04b00 EDI: 00002212 EBP: f473c000 ESP: f473dfa4
 DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068
Process sshd (pid: 8722, ti=f473c000 task=f3c64560 task.ti=f473c000)
Stack: c012277b 00000000 00000000 00000000 c0104086 00000000 00000135 00000135
       00000000 00000000 080aea00 00000042 0000007b 0000007b 00000000 00000042
       b7f20424 00000073 00000246 bfa3987c 0000007b 00000000 00000000
Call Trace:
 [<c012277b>] sys_setsid+0x54/0x70
 [<c0104086>] sysenter_past_esp+0x5f/0x85
 =======================


Steps to reproduce: