Re: [PATCH] KVM: VMX: Zero host's SYSENTER_ESP iff SYSENTER is NOT used

[Paolo Bonzini]

On 1/22/22 09:47, Vitaly Kuznetsov wrote:
> >   	 */
> > -	vmcs_writel(HOST_IA32_SYSENTER_ESP, 0);
> > +	if (!IS_ENABLED(CONFIG_IA32_EMULATION) && !IS_ENABLED(CONFIG_X86_32))
> Isn't it the same as "!IS_ENABLED(CONFIG_COMPAT_32)"? (same goes to the
> check in vmx_vcpu_load_vmcs())

It is, but I think it's clearer to write it as it's already done in 
arch/x86/kvm/vmx/vmx.c, or possibly

if (IS_ENABLED(CONFIG_X86_64) && !IS_ENABLED(CONFIG_IA32_EMULATION))

CONFIG_COMPAT_32 doesn't say as clearly whether it's enabled for 32-bit 
systems or not.

Paolo