cpu_interrpt() is probably not threadsafe.

う～む。

/* mask must never be zero, except for A20 change call */

void cpu_interrupt(CPUState *env, int mask)

{

。。。

    /* FIXME: This is probably not threadsafe.  A different thread could

       be in the middle of a read-modify-write operation.  */

    env->interrupt_request |= mask;

#if defined(USE_NPTL)

    /* FIXME: TB unchaining isn't SMP safe.  For now just ignore the

       problem and hope the cpu will stop of its own accord.  For userspace

       emulation this often isn't actually as bad as it sounds.  Often

       signals are used primarily to interrupt blocking syscalls.  */

#else

       。。。

}