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From: Paolo Bonzini <pbonzini@redhat.com>
Date: Tue, 30 Jun 2020 07:07:20 -0400
Subject: KVM: x86: bit 8 of non-leaf PDPEs is not reserved
Git-commit: 5ecad245de2ae23dc4e2dbece92f8ccfbaed2fa7
Patch-mainline: v5.8-rc5
References: bsc#1188790

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>
Signed-off-by: Jose R. Ziviani <jziviani@suse.de>
---
 arch/x86/kvm/mmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index bee0b7a0da34..22adc92e3217 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -4527,7 +4527,7 @@ __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);
-- 
2.32.0