Messages in this thread | | | Subject | Re: [PATCH v7 008/102] KVM: x86: Refactor KVM VMX module init/exit functions | From | Kai Huang <> | Date | Tue, 12 Jul 2022 13:30:34 +1200 |
| |
On Mon, 2022-07-11 at 17:38 -0700, Isaku Yamahata wrote: > On Tue, Jun 28, 2022 at 03:53:31PM +1200, > Kai Huang <kai.huang@intel.com> wrote: > > > On Mon, 2022-06-27 at 14:53 -0700, isaku.yamahata@intel.com wrote: > > > From: Isaku Yamahata <isaku.yamahata@intel.com> > > > > > > Currently, KVM VMX module initialization/exit functions are a single > > > function each. Refactor KVM VMX module initialization functions into KVM > > > common part and VMX part so that TDX specific part can be added cleanly. > > > Opportunistically refactor module exit function as well. > > > > > > The current module initialization flow is, 1.) calculate the sizes of VMX > > > kvm structure and VMX vcpu structure, 2.) hyper-v specific initialization > > > 3.) report those sizes to the KVM common layer and KVM common > > > initialization, and 4.) VMX specific system-wide initialization. > > > > > > Refactor the KVM VMX module initialization function into functions with a > > > wrapper function to separate VMX logic in vmx.c from a file, main.c, common > > > among VMX and TDX. We have a wrapper function, "vt_init() {vmx kvm/vcpu > > > size calculation; hv_vp_assist_page_init(); kvm_init(); vmx_init(); }" in > > > main.c, and hv_vp_assist_page_init() and vmx_init() in vmx.c. > > > hv_vp_assist_page_init() initializes hyper-v specific assist pages, > > > kvm_init() does system-wide initialization of the KVM common layer, and > > > vmx_init() does system-wide VMX initialization. > > > > > > The KVM architecture common layer allocates struct kvm with reported size > > > for architecture-specific code. The KVM VMX module defines its structure > > > as struct vmx_kvm { struct kvm; VMX specific members;} and uses it as > > > struct vmx kvm. Similar for vcpu structure. TDX KVM patches will define > > > TDX specific kvm and vcpu structures, add tdx_pre_kvm_init() to report the > > > sizes of them to the KVM common layer. > > > > > > The current module exit function is also a single function, a combination > > > of VMX specific logic and common KVM logic. Refactor it into VMX specific > > > logic and KVM common logic. This is just refactoring to keep the VMX > > > specific logic in vmx.c from main.c. > > > > This patch, coupled with the patch: > > > > KVM: VMX: Move out vmx_x86_ops to 'main.c' to wrap VMX and TDX > > > > Basically provides an infrastructure to support both VMX and TDX. Why we cannot > > merge them into one patch? What's the benefit of splitting them? > > > > At least, why the two patches cannot be put together closely? > > It is trivial for the change of "KVM: VMX: Move out vmx_x86_ops to 'main.c' to > wrap VMX and TDX" to introduce no functional change. But it's not trivial > for this patch to introduce no functional change.
This doesn't sound right. If I understand correctly, this patch supposedly shouldn't bring any functional change, right? Could you explain what functional change does this patch bring?
| |