Description of problem: (Bug found by Laszlo Ersek) -append "... earlyprintk=pl011,,0x9000000 ..." The , does not need to be quoted (doubled) in this case. Version-Release number of selected component (if applicable): libguestfs 1.40 How reproducible: 100% Steps to Reproduce: 1. LIBGUESTFS_BACKEND=direct libguestfs-test-tool 2. Examine the -append parameter passed to qemu. Additional info: Note this doesn't seem to make any functional difference.