This bug also happened on qemu-kvm-1.5.3-103.el7.
(gdb) r -display vnc=unix:/blabla/bla
Starting program: /usr/libexec/qemu-kvm -display vnc=unix:/blabla/bla
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
[New Thread 0x7fffe8372700 (LWP 16978)]
[New Thread 0x7fffde1ff700 (LWP 16980)]
qemu-kvm: iohandler.c:60: qemu_set_fd_handler2: Assertion `fd >= 0' failed.
Program received signal SIGABRT, Aborted.
0x00007ffff10e35f7 in raise () from /lib64/libc.so.6
7.2 is blocker+exceptions, this isn't *that* important, defering to 7.3
Upstream commit 3d00ac1a2ee0294fc3d460e6013a5cdd9c73ea6c is in 2.4.0
So fixed by rebase.
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.