[libvirt] Bug: iohelper drops I/O error messages

During a recent managed save operation I received the following error message: error: operation failed: domain save job: unexpectedly failed. It turns out that I had run out of disk space. After a brief investigation I discovered that libvirt_iohelper is exec'ed and is used to handle all I/O during a (Qemu) managed save operation. While iohelper appears to be set up to log error conditions when they occur, for some reason the logging is getting lost. I'm hoping someone can help figure out why these errors are getting lost. It would be nice to present a useful error message to the user when a managed save fails because of an I/O error. I was able to work around this problem with a patch that bypasses iohelper entirely but I doubt that is really the best thing to do. Does anyone know why these error messages are getting suppressed?