[PATCH v4 2/9] KVM: x86: MMU: Clear CR3 LAM bits when allocate shadow root

Robert Hoo
2023-02-09T02:41:46Z

mmu->get_guest_pgd()'s implementation is get_cr3(), clear the LAM bits for
root_pgd, which needs a pure address, plus (possible) PCID info (low 12
bits).

Signed-off-by: Robert Hoo <robert.hu@linux.intel.com>
---
arch/x86/kvm/mmu/mmu.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 835426254e76..1d61dfe37c77 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -3698,8 +3698,11 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu)
gfn_t root_gfn, root_pgd;
int quadrant, i, r;
hpa_t root;
-
+#ifdef CONFIG_X86_64
+ root_pgd = mmu->get_guest_pgd(vcpu) & ~(X86_CR3_LAM_U48 | X86_CR3_LAM_U57);
+#else
root_pgd = mmu->get_guest_pgd(vcpu);
+#endif
root_gfn = root_pgd >> PAGE_SHIFT;

if (mmu_check_root(vcpu, root_gfn))
--
2.31.1