On 12/17/19 2:58 PM, Cole Robinson wrote:
On 12/12/19 4:11 PM, Daniel Henrique Barboza wrote:
POWER hosts does not implement CPU virtualization extensions like x86 or s390x. Instead, all bare-metal POWER hosts are considered to be virtualization ready.
For POWER, the validation is done by checking the virtualization kernel modules, kvm_hv and kvm_pr, to see if they are either not installed or not loaded in the host. If the KVM modules aren't present, we should not just warn but fail to validate.
This patch implements this support. If kvm_hv is not installed, which can be determined by 'modinfo' returning not-zero return code, fail the verification. If kvm_hv is installed but not loaded, show a warning. The exception are POWER8 hosts, which can work with kvm_pr. In its case, ACK the use of kvm_pr if kvm_hv is not loaded/present.
For x86, we check for /dev/kvm being available and usable. This side steps whether kvm is a module or not, in theory it could be compiled into the kernel. Is there anything in /dev we can check for power8?
I don't know. I'll investigate.
I don't follow the reasoning for for why the module is installed vs loaded matters for FAIL vs WARN. Can you expand on that a bit more?
The reasoning is that the module not present (i.e. not compiled in the kernel) is not easy to solve, while the module not loaded is a matter of loading either kvm_pr or kvm_hv. The nonexistence of both kvm_pr and kvm_hv is something I haven't seen in the field and I'm somewhat theorizing about it. I wouldn't oppose to simply check for the modules being loaded and use WARN.
Rather than parsing /proc/modinfo, can we check for /sys/module/$modname instead, or something under that directory?
Just checked. If the existence of say /sys/module/kvm_hv is an indication that the module kvm_hv is loaded, then I see no issues with checking for this instead of parsing modinfo. Thanks, DHB
- Cole