On Monday, March 13, 2023 1:55 AM, isaku.yamahata@xxxxxxxxx wrote:
> 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,
> 0.) Check if VMX is supported,
> 1.) hyper-v specific initialization,
> 2.) system-wide x86 specific and vendor specific initialization,
> 3.) Final VMX specific system-wide initialization,
> 4.) calculate the sizes of VMX kvm structure and VMX vcpu structure,
> 5.) report those sizes to the KVM common layer and KVM common
> 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. Introduce a wrapper function for vmx_init().
>
> 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.
>
> 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.
>
> Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
> ---
> arch/x86/kvm/vmx/main.c | 51 +++++++++++++++++++++++++++++++++++
> arch/x86/kvm/vmx/vmx.c | 54 +++++---------------------------------
> arch/x86/kvm/vmx/x86_ops.h | 13 ++++++++-
> 3 files changed, 69 insertions(+), 49 deletions(-)
>
> diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c index
> a59559ff140e..3f49e8e38b6b 100644
> --- a/arch/x86/kvm/vmx/main.c
> +++ b/arch/x86/kvm/vmx/main.c
> @@ -165,3 +165,54 @@ struct kvm_x86_init_ops vt_init_ops __initdata = {
> .runtime_ops = &vt_x86_ops,
> .pmu_ops = &intel_pmu_ops,
> };
> +
> +static int __init vt_init(void)
> +{
> + unsigned int vcpu_size, vcpu_align;
> + int r;
> +
> + if (!kvm_is_vmx_supported())
> + return -EOPNOTSUPP;
> +
> + /*
> + * Note, hv_init_evmcs() touches only VMX knobs, i.e. there's nothing
> + * to unwind if a later step fails.
> + */
> + hv_init_evmcs();
> +
> + r = kvm_x86_vendor_init(&vt_init_ops);
> + if (r)
> + return r;
> +
> + r = vmx_init();
> + if (r)
> + goto err_vmx_init;
> +
> + /*
> + * Common KVM initialization _must_ come last, after this, /dev/kvm is
> + * exposed to userspace!
> + */
> + vt_x86_ops.vm_size = sizeof(struct kvm_vmx);
> + vcpu_size = sizeof(struct vcpu_vmx);
> + vcpu_align = __alignof__(struct vcpu_vmx);
> + r = kvm_init(vcpu_size, vcpu_align, THIS_MODULE);
> + if (r)
> + goto err_kvm_init;
> +
> + return 0;
> +
> +err_kvm_init:
> + vmx_exit();
> +err_vmx_init:
> + kvm_x86_vendor_exit();
> + return r;
> +}
> +module_init(vt_init);
I had a patch to fix a bug here, maybe you can take it:
kvm_x86_vendor_init copies vt_x86_ops to kvm_x86_ops. vt_x86_ops.vm_size
needs to be updated before calling kvm_x86_vendor_init so that kvm_x86_ops
can get the correct vm_size.
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 41f07d92aaf6..37a8c212c653 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -1126,18 +1126,6 @@ static int __init vt_init(void)
*/
hv_init_evmcs();
- r = kvm_x86_vendor_init(&vt_init_ops);
- if (r)
- return r;
-
- r = vmx_init();
- if (r)
- goto err_vmx_init;
-
- r = tdx_init();
- if (r)
- goto err_tdx_init;
-
/*
* Common KVM initialization _must_ come last, after this, /dev/kvm is
* exposed to userspace!
@@ -1153,6 +1141,19 @@ static int __init vt_init(void)
vcpu_align = max_t(unsigned int, vcpu_align,
__alignof__(struct vcpu_tdx));
}
+
+ r = kvm_x86_vendor_init(&vt_init_ops);
+ if (r)
+ return r;
+
+ r = vmx_init();
+ if (r)
+ goto err_vmx_init;
+
+ r = tdx_init();
+ if (r)
+ goto err_tdx_init;
+
r = kvm_init(vcpu_size, vcpu_align, THIS_MODULE);
if (r)
goto err_kvm_init;
--
