On 15/01/19 03:43, Sean Christopherson wrote: >> - vmx->nested.cached_vmcs12 = kmalloc(VMCS12_SIZE, GFP_KERNEL); >> + vmx->nested.cached_vmcs12 = kzalloc(VMCS12_SIZE, GFP_KERNEL); >> if (!vmx->nested.cached_vmcs12) >> goto out_cached_vmcs12; > Obviously not your code, but why do we allocate VMCS12_SIZE instead of > sizeof(struct vmcs12)? I get why we require userspace to reserve the > full 4k, but I don't understand why KVM needs to allocate the reserved > bytes internally.
It's just cleaner and shorter code to copy everything in and out, instead of having to explicitly zero the slack. Paolo
