From: Krish Sadhukhan <[email protected]>

[ Upstream commit fb0f33fdefe9f473dc5f7b71345096c8d60ab9dd ]

Commit 761e4169346553c180bbd4a383aedd72f905bc9a created a wrong mask for the
CR3 MBZ bits. According to APM vol 2, only the upper 12 bits are MBZ.

Fixes: 761e41693465 ("KVM: nSVM: Check that MBZ bits in CR3 and CR4 are not set 
on vmrun of nested guests", 2020-07-08)
Signed-off-by: Krish Sadhukhan <[email protected]>
Message-Id: <[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
---
 arch/x86/kvm/svm/nested.c | 2 +-
 arch/x86/kvm/svm/svm.h    | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index e90bc436f5849..27042c9ea40d6 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -243,7 +243,7 @@ static bool nested_vmcb_checks(struct vcpu_svm *svm, struct 
vmcb *vmcb)
        } else {
                if (!(vmcb->save.cr4 & X86_CR4_PAE) ||
                    !(vmcb->save.cr0 & X86_CR0_PE) ||
-                   (vmcb->save.cr3 & MSR_CR3_LONG_RESERVED_MASK))
+                   (vmcb->save.cr3 & MSR_CR3_LONG_MBZ_MASK))
                        return false;
        }
        if (kvm_valid_cr4(&svm->vcpu, vmcb->save.cr4))
diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index a798e17317094..c0d75b1e06645 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -345,7 +345,7 @@ static inline bool gif_set(struct vcpu_svm *svm)
 /* svm.c */
 #define MSR_CR3_LEGACY_RESERVED_MASK           0xfe7U
 #define MSR_CR3_LEGACY_PAE_RESERVED_MASK       0x7U
-#define MSR_CR3_LONG_RESERVED_MASK             0xfff0000000000fe7U
+#define MSR_CR3_LONG_MBZ_MASK                  0xfff0000000000000U
 #define MSR_INVALID                            0xffffffffU
 
 u32 svm_msrpm_offset(u32 msr);
-- 
2.25.1



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