[Qemu-discuss] qemu spins loops when pass > ~265 nics

[b f31415]

I’m seeing an odd issue with qemu-system-x86_64 when trying to spin up a VM
with 100s of network interfaces.  For this specific VM I’m passing (via
multiple –network statements) 475 interfaces.   I’m launching this with
virt-install.   The VM starts and is running but apparently gets stuck
 early in the boot process in some sort of polling loop (based on an
strace).    The VM reports no issues to the serial port and the video
output reports guest has not initialized the display yet. The issue seems
to be with the number of network interfaces.  If I trim the network list
down to ~265 interfaces or fewer, the VM fully boots and all ~265
interfaces operate as expected.



The host is ubuntu 16.04 and I’m running qemu 2.5.0.



Any insights into what issue might be causing qemu-system to effectively
loop when passing in > 265-ish network interfaces or troubleshooting steps
which might shed line on what the issue is?



Thanks