KVM: x86: bit 8 of non-leaf PDPEs is not reserved

Bit 8 would be the "global" bit, which does not quite make sense for non-leaf
page table entries.  Intel ignores it; AMD ignores it in PDEs and PDPEs, but
reserves it in PML4Es.

Probably, earlier versions of the AMD manual documented it as reserved in PDPEs
as well, and that behavior made it into KVM as well as kvm-unit-tests; fix it.

Cc: stable@vger.kernel.org
Reported-by: Nadav Amit <namit@vmware.com>
Fixes: a0c0feb57992 ("KVM: x86: reserve bit 8 of non-leaf PDPEs and PML4Es in 64-bit mode on AMD", 2014-09-03)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 76817d13c86ed886e1b694e898de744d9f028653..6d6a0ae7800c60d75c5aae424cc9bc5707d88f5e 100644 (file)
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4449,7 +4449,7 @@ __reset_rsvds_bits_mask(struct kvm_vcpu *vcpu,
                        nonleaf_bit8_rsvd | rsvd_bits(7, 7) |
                        rsvd_bits(maxphyaddr, 51);
                rsvd_check->rsvd_bits_mask[0][2] = exb_bit_rsvd |
-                       nonleaf_bit8_rsvd | gbpages_bit_rsvd |
+                       gbpages_bit_rsvd |
                        rsvd_bits(maxphyaddr, 51);
                rsvd_check->rsvd_bits_mask[0][1] = exb_bit_rsvd |
                        rsvd_bits(maxphyaddr, 51);