On 2/8/2019 8:07 PM, Sijmen J. Mulder wrote:
Hi,I run OpenBSD (snapshots) in a KVM+QEMU VM on Debian 9 and use it over SSH. Those SSH sessions stall almost without fail when there's a lot of output. Repro (or at least my set up): 1. Create a KVM+QMEU VM on Linux with virt-manager. I assigned two cores and otherwise used defaults. 2. Install an OpenBSD snapshot. 3. In an SSH session, execute 'find /' until hang. I suspect other large network transfers may result in the same. Symptoms: - SSH session stalls with no output, no echo, and no response to ^C. - New communication (SSH, ping) cannot be established: "no route to host" - The serial console outputs "re0: watchdog timeout" - From the serial code, pinging the host yields "ping: sendmsg: No buffer space available" Workaround: 'ifconfig re0 down; ifconfig re0 up' and a little patience fixes it. Below, the VM's dmesg and its libvirt XML dump. After seeing the NFS messages I unmounted the shares but the behaviour was the same. Sijmen
Why rtl8139? It's the worst option available to KVM/QEMU. You would be much better off with virtio or e1000 for the NIC.
