[RFC PATCH v4 06/18] kvm: vmx: export the availability of EPT views

["Adalber Lazăr" <alazar@bitdefender.com>]

From: Adalbert Lazar <alazar@bitdefender.com>

This is used to validate the KVMI_GET_PAGE_ACCESS and KVMI_SET_PAGE_ACCESS
commands when the guest introspection tool selects a different EPT view.

Signed-off-by: Adalbert Lazăr <alazar@bitdefender.com>
---
 arch/x86/include/asm/kvm_host.h | 1 +
 arch/x86/kvm/vmx.c              | 2 ++
 arch/x86/kvm/x86.c              | 3 +++
 3 files changed, 6 insertions(+)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 239eb628f8fb..2cf03ed181e6 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1162,6 +1162,7 @@ extern u64  kvm_max_tsc_scaling_ratio;
 extern u64  kvm_default_tsc_scaling_ratio;
 
 extern u64 kvm_mce_cap_supported;
+extern bool kvm_eptp_switching_supported;
 
 enum emulation_result {
 	EMULATE_DONE,         /* no further processing */
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 5487e0242030..093a2e1f7ea6 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -6898,6 +6898,8 @@ static __init int hardware_setup(void)
 		kvm_x86_ops->cancel_hv_timer = NULL;
 	}
 
+	kvm_eptp_switching_supported = cpu_has_vmx_vmfunc();
+
 	kvm_set_posted_intr_wakeup_handler(wakeup_handler);
 
 	kvm_mce_cap_supported |= MCG_LMCE_P;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 4b0c3692386d..e7db70ac1f82 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -138,6 +138,9 @@ module_param(lapic_timer_advance_ns, uint, S_IRUGO | S_IWUSR);
 static bool __read_mostly vector_hashing = true;
 module_param(vector_hashing, bool, S_IRUGO);
 
+bool __read_mostly kvm_eptp_switching_supported;
+EXPORT_SYMBOL_GPL(kvm_eptp_switching_supported);
+
 #define KVM_NR_SHARED_MSRS 16
 
 struct kvm_shared_msrs_global {