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Message-ID: <8baca98e-63d6-f7dd-067b-05f8e0dc381f@redhat.com>
Date:   Thu, 26 May 2022 12:39:54 +0200
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Subject: Re: [PATCH 1/2] KVM: VMX: Sanitize VM-Entry/VM-Exit control pairs at
 kvm_intel load time
Content-Language: en-US
To:     Sean Christopherson <seanjc@google.com>
Cc:     Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Chenyi Qiang <chenyi.qiang@intel.com>,
        Lei Wang <lei4.wang@intel.com>
References: <20220525210447.2758436-1-seanjc@google.com>
 <20220525210447.2758436-2-seanjc@google.com>
From:   Paolo Bonzini <pbonzini@redhat.com>
In-Reply-To: <20220525210447.2758436-2-seanjc@google.com>
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On 5/25/22 23:04, Sean Christopherson wrote:
>   
> +#define VMCS_ENTRY_EXIT_PAIR(name, entry_action, exit_action) \
> +	{ VM_ENTRY_##entry_action##_##name, VM_EXIT_##exit_action##_##name }
> +
>   static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,
>   				    struct vmx_capability *vmx_cap)
>   {
> @@ -2473,6 +2476,24 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,
>   	u64 _cpu_based_3rd_exec_control = 0;
>   	u32 _vmexit_control = 0;
>   	u32 _vmentry_control = 0;
> +	int i;
> +
> +	/*
> +	 * LOAD/SAVE_DEBUG_CONTROLS are absent because both are mandatory.
> +	 * SAVE_IA32_PAT and SAVE_IA32_EFER are absent because KVM always
> +	 * intercepts writes to PAT and EFER, i.e. never enables those controls.
> +	 */
> +	struct {
> +		u32 entry_control;
> +		u32 exit_control;
> +	} vmcs_entry_exit_pairs[] = {
> +		VMCS_ENTRY_EXIT_PAIR(IA32_PERF_GLOBAL_CTRL, LOAD, LOAD),
> +		VMCS_ENTRY_EXIT_PAIR(IA32_PAT, LOAD, LOAD),
> +		VMCS_ENTRY_EXIT_PAIR(IA32_EFER, LOAD, LOAD),
> +		VMCS_ENTRY_EXIT_PAIR(BNDCFGS, LOAD, CLEAR),
> +		VMCS_ENTRY_EXIT_PAIR(IA32_RTIT_CTL, LOAD, CLEAR),
> +		VMCS_ENTRY_EXIT_PAIR(IA32_LBR_CTL, LOAD, CLEAR),

No macros please, it's just as clear to expand them especially since the 
#define is far from the struct definition.

Paolo