The trap handler does properly update the fraction,
but not the exponent...

Thanks to Paolo Bonzini for the bug report and the testcase.
Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Paolo Bonzini <bonzini@gnu.org>
Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>