Possible Filesystem Corruption

[John Duncan <agley@xxxxxxxxxxxxxxx>]

Hi,
   I am using HEAD last built about a week ago. For a while I have been
   getting a random number of disks in the line that says syncing disks
   when shutting down. Today I had a few more problems i.e. in /bin/csh
   and /bin/tcsh I got

        /bin/pwd : 1 syntax error: ``( '' unexpected

   also /usr/src was no longer seen as a directory and ls said it had a
   bad file descriptor for /usr/src. Then when shutting down I got a
   panic. I didn't know what to do at db> but typing panic ? got me a
   reboot and the subsequent fsck seems to have fixed everything I can
   check. There was something about a SUPERBLOCK but it was too fast for
   me to record. Not all filesystems were checked probably because the
   system was already in single user mode when it paniced ?.

 Here is the panic FYI, it is hand transcribed.

syncing disks... 2
done
panic: umount: dangling vnode
Trace beginning at frame 0xc5423ae0
panic(c04f58af,c05b14a0,c04f7fc7,c5423b10,0) at panic+0x99
dounmount(c0df6588,80000,c5420f00,1,c0df6588) at dounmount+0x23a
vfs_unmountall_callback(c0df6588,c5423bb0,c4dfee00,c5420f00,c05b5c88) at
   vfs_unmountall_callback+0x28
mountlist_scan(c02ebabe,c5423bb0,6,c5420f00,c5420f00) at
   mountlist_scan+0x11a
vfs_unmountall(c04ec5be,0,c04f57c3,1,2) at vfs_unmountall+0x42
boot(8,c5423d40,c04a3434,c5423c24,c5423d10) at boot+0x352
reboot(c5423c24,c5423d10,4,c041302e,1) at reboot+0x2c
syscall2(2f,2f,2f,2,bfbffabc) at syscall2+0x25f
Xint0x80_syscall() at Xint0x80_syscall+0x2a
Debugger("panic")
Stopped at Debugger+0x44: movb   $0,in_Debugger.0

                               Hope this helps,
                                  John Duncan