Re: [PATCH v19 021/130] KVM: x86/vmx: initialize loaded_vmcss_on_cpu in vmx_init()

[Binbin Wu]

On 2/26/2024 4:25 PM, isaku.yamahata@xxxxxxxxx wrote:
> From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
>
> vmx_hardware_disable() accesses loaded_vmcss_on_cpu via
> hardware_disable_all().  To allow hardware_enable/disable_all() before
> kvm_init(), initialize it in before kvm_x86_vendor_init() in vmx_init()
> so that tdx module initialization, hardware_setup method, can reference
> the variable.
>
> Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
> Reviewed-by: Yuan Yao <yuan.yao@xxxxxxxxx>

The shortlog should be this?
KVM: VMX: Initialize loaded_vmcss_on_cpu in vmx_init()

Others,
Reviewed-by: Binbin Wu <binbin.wu@xxxxxxxxxxxxxxx>

> ---
> v19:
> - Fix the subject to match the patch by Yuan
>
> v18:
> - Move the vmcss_on_cpu initialization from vmx_hardware_setup() to
>    early point of vmx_init() by Binbin
>
> Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
> ---
>   arch/x86/kvm/vmx/vmx.c | 9 +++++----
>   1 file changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
> index 434f5aaef030..8af0668e4dca 100644
> --- a/arch/x86/kvm/vmx/vmx.c
> +++ b/arch/x86/kvm/vmx/vmx.c
> @@ -8539,6 +8539,10 @@ static int __init vmx_init(void)
>   	 */
>   	hv_init_evmcs();
>   
> +	/* vmx_hardware_disable() accesses loaded_vmcss_on_cpu. */
> +	for_each_possible_cpu(cpu)
> +		INIT_LIST_HEAD(&per_cpu(loaded_vmcss_on_cpu, cpu));
> +
>   	r = kvm_x86_vendor_init(&vt_init_ops);
>   	if (r)
>   		return r;
> @@ -8554,11 +8558,8 @@ static int __init vmx_init(void)
>   	if (r)
>   		goto err_l1d_flush;
>   
> -	for_each_possible_cpu(cpu) {
> -		INIT_LIST_HEAD(&per_cpu(loaded_vmcss_on_cpu, cpu));
> -
> +	for_each_possible_cpu(cpu)
>   		pi_init_cpu(cpu);
> -	}
>   
>   	cpu_emergency_register_virt_callback(vmx_emergency_disable);
>