Warning: virtio-net with win2012R2 and kernel < 2.6.32-30

udo

Distinguished Member
Apr 22, 2009
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Ahrensburg; Germany
Hi,
found bad news.
If you have an win2012 server with virtio-net and modify inside the guest the parameter init.MaxRxBuffers from 256 (default) to 512 the pvehost and other VMs loose the network-connection or an kernel-panic occur!

This happens with virtio 0.74 + 0.81.

If you run the new kernel 2.6.32-30 the win2012-VM loose the network connectiviy only.
I havn't look if the same issue on win8 occur.


Udo
 
I just tested this on win2012r2, running on 2.6.32-30 and kvm 2.0 (git version) and the guest looses network. other services are not interrupted as far as I see.
 
... Kernel below -30 are the problem.

Udo

a good reason to use latest kernel (2.6.32-30 is the current stable).