[libvirt] the POLLHUP envet for a pipe descriptor is the cause that the libvirt_lxc costs 100% cpu usage.

I found the poll in virEventPollRunOnce (vireventpoll.c), a POLLHUP event occurred for a pipe descriptor, thus the poll always returned because of it.( the pipe broken). this may be the best I could track temporarily，I don't know what to do netx , to mask the hangup event or to do something to handle the hangup event , what to do ? Is it a bug or something ? any help would be appreciate. :)