Page allocation and de-allocation

[Xiangfei Jia <xjianz@xxxxxxxxx>]

I'm using an array to hold number of pages. The array is allocated
using vmalloc and each page is allocated by
get_free_page(GFP_ATOMIC).  And after use, the number of pages are
free-ed by __free_page(). 

The system works fine if the array of pages are allocated for the first
time since the system started running. If I try to allocate the same
amount of pages for the second time, the system will crash. Even if I
try to allocate less pages, the system still crashes. It seems to me
that the the pages been allocated are not really free-ed. Or maybe due
to some other problems. Can someone help me with this. Really
appropriated!!

Thanks!

Fei