> Yes, > > qemu is connecting the serial port to a FIFO, and qemu is resident > even after host reboot. > > In fact, even if you'll kill the qemu process and restart it with the > same FIFO, it should still work. > > Please try it, and report if it indeed worked for you. Frankly I'm still having some problems. But let me tell you a full story first. I have Ubuntu 14.04 LTS installed on my laptop Fujitsu Lifebook E733. I created two VMs with FreeBSD 11.0 CURRENT. What I'm trying to do is to debug a FreeBSD kernel using kgdb, thus I need two systems connected via serial port. Unfortunately using mkfifo as you described above didn't work. Right solution was found here: http://blog.bauermann.eng.br/2013/09/04/connecting-qemukvm-virtual-machines-via-serial-port/ Now when I start VMs: sudo kvm -hda /path/to/freebsd11.img \ -serial pipe:/path/to/null-cable-1 sudo kvm -hda /path/to/freebsd11kgdb.img \ -serial pipe:/path/to/null-cable-2 ... serial port (/dev/cuau0) is seen in both VMs. Then I edited /boot/device.hints on freebsd11 VM like this: hint.uart.0.flags="0x90" ..., restarted this VM, entered boot prompt (by pressing 3 in boot menu), and typed: boot kernel -d This command boots kernel in debug mode. In DDB prompt I typed: gdb Now system awaits connection from 2nd system by serial port. Here is how to do this: su cd /usr/src sudo kgdb -r /dev/cuau0 /boot/kernel/kernel Good news is --- it works! http://i.imgur.com/bP8uioX.png But I don't have a network connection and other stuff I configured using `virsh`. So I tried `virsh edit MVNAME` as described here: http://blog.vmsplice.net/2011/04/how-to-pass-qemu-command-line-options.html Unfortunately now when I start VM I got an error: ``` eax@fujitsu:~$ sudo virsh start freebsd11 error: Failed to start domain freebsd11 error: internal error: process exited while connecting to monitor: qemu-system-x86_64: -serial pipe:/var/lib/libvirt/pipes/null-cable-1: Failed to create chardev qemu: could not connect serial device to character backend 'pipe:/var/lib/libvirt/pipes/null-cable-1' ``` Here is a full `sudo virsh dumpxml freebsd11` output: http://paste.ubuntu.com/15386277/ Here is part of /var/log/libvirt/qemu/freebsd11.log, which contains long KVM command executed by virsh: http://paste.ubuntu.com/15386302/ And here is how `sudo strace virsh start freebsd11` looks like: http://paste.ubuntu.com/15386306/ Any ideas how to solve this issue? Naturally if there is any other debug information you need I will be happy to provide it. Best regards, Aleksander Alekseev http://eax.me/ -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
