KVM: VMX: Ignore MKTME KeyID bits when intercepting #PF for allow_smaller_maxphyaddr

Use the raw/true host.MAXPHYADDR when deciding whether or not KVM must
intercept #PFs when allow_smaller_maxphyaddr is enabled, as any adjustments
the kernel makes to boot_cpu_data.x86_phys_bits to account for MKTME KeyID
bits do not apply to the guest physical address space.  I.e. the KeyID are
off-limits for host physical addresses, but are not reserved for GPAs as
far as hardware is concerned.

Signed-off-by: Tao Su <tao1.su@linux.intel.com>
Link: https://lore.kernel.org/r/20240319031111.495006-1-tao1.su@linux.intel.com
[sean: massage changelog]
Signed-off-by: Sean Christopherson <seanjc@google.com>

diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 65786dbe7d60bdf753db779312bb70754ccc6f1e..1742c88ba9c8066a7329355b830fabd5ca0a1b51 100644 (file)
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -15,6 +15,7 @@
 #include "vmx_ops.h"
 #include "../cpuid.h"
 #include "run_flags.h"
+#include "../mmu.h"
 
 #define MSR_TYPE_R     1
 #define MSR_TYPE_W     2
@@ -719,7 +720,8 @@ static inline bool vmx_need_pf_intercept(struct kvm_vcpu *vcpu)
        if (!enable_ept)
                return true;
 
-       return allow_smaller_maxphyaddr && cpuid_maxphyaddr(vcpu) < boot_cpu_data.x86_phys_bits;
+       return allow_smaller_maxphyaddr &&
+              cpuid_maxphyaddr(vcpu) < kvm_get_shadow_phys_bits();
 }
 
 static inline bool is_unrestricted_guest(struct kvm_vcpu *vcpu)