ufs_rename: fvp == tvp (can't happen), but it did

[perryh at pluto.rain.com]

> The problem is the following: on machine A the mail spool is on a local 
> disk array (via ciss). On machine B we run experiments with an FC disk 
> array, so the e-mails are on gmirror'ed filesystems (on ciss for the 
> local disks and on isp for the FC array).
>
> The strange thing happens when both the local and FC disks are working 
> in the mirrors. I get the following warning very often:
> ufs_rename: fvp == tvp (can't happen)
>
> If I do a gmirror remove for the FC array, these go away. Also, the 
> other machine (with only local disks) is free from this.

It sounds as if the caller of ufs_rename() is confused.  You could
try setting a breakpoint on the printf(), or change it to a panic()
to get a dump, and try to figure out who the caller is and what is
going on.