Set up signalfd under !CONFIG_IOTHREAD Will be required for SIGBUS handling. For obvious reasons, this will remain a nop on Windows hosts. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>