Problems with FreeBSD 7.1 Pre-Release after Upgrade from 7.0

[limguowei at gmail.com]

After cvsuping the source and recompiling the kernel from 7.0 
The follow programs produce error
I created a memory disk for a /temp in FreeBSD 7.0 upon upgrading to 7.1 it refuses to created and mount /dev/md0 as successful in 7.0
pid 977/978 (mdconfig) uid 0 exit from signal 11 (core dumped)
pid 977 (mdconfig), uid 0: exited on signal 11 (core dumped)
pid 978 (mdconfig), uid 0: exited on signal 11 (core dumped)
And when i used kldstat the same thing happens after printing one entry 
# kldstat
Id Refs Address    Size     Name
 1   12 0xc0400000 625fe0   kernel
Segmentation fault (core dumped)