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

[Paolo Bonzini]

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.

How is the bug reproducible?

Paolo