Re: [PATCH] KVM: X86: Dynamically allocating MSR number lists(msrs_to_save[], emulated_msrs[], msr_based_features[])

[Paolo Bonzini]

On 05/11/19 12:11, Xiaoyao Li wrote:
> On 11/5/2019 6:41 PM, Paolo Bonzini wrote:
>> On 05/11/19 10:20, Chenyi Qiang wrote:
>>> The three msr number lists(msrs_to_save[], emulated_msrs[] and
>>> msr_based_features[]) are global arrays of kvm.ko, which are
>>> initialized/adjusted (copy supported MSRs forward to override the
>>> unsupported MSRs) when installing kvm-{intel,amd}.ko, but it doesn't
>>> reset these three arrays to their initial value when uninstalling
>>> kvm-{intel,amd}.ko. Thus, at the next installation, kvm-{intel,amd}.ko
>>> will initialize the modified arrays with some MSRs lost and some MSRs
>>> duplicated.
>>>
>>> So allocate and initialize these three MSR number lists dynamically when
>>> installing kvm-{intel,amd}.ko and free them when uninstalling.
>>
>> I don't understand. Do you mean insmod/rmmod when you say
>> installing/uninstalling? Global data must be reloaded from the ELF file
>> when insmod is executed.
> 
> Yes, we mean insmod/rmmod.
> The problem is that these three MSR arrays belong to kvm.ko but not
> kvm-{intel,amd}.ko. When we rmmod kvm_intel.ko, it does nothing to them.

Ok, thanks for the explanation.

Paolo