From 5f7dde7bbb3c628766676cbd63c0a1834035d6fa Mon Sep 17 00:00:00 2001 From: Nadav Amit Date: Wed, 7 May 2014 15:32:50 +0300 Subject: [PATCH] KVM: x86: Mark bit 7 in long-mode PDPTE according to 1GB pages support In long-mode, bit 7 in the PDPTE is not reserved only if 1GB pages are supported by the CPU. Currently the bit is considered by KVM as always reserved. Signed-off-by: Nadav Amit Signed-off-by: Paolo Bonzini --- arch/x86/kvm/cpuid.h | 7 +++++++ arch/x86/kvm/mmu.c | 8 ++++++-- 2 files changed, 13 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h index eeecbed26ac7..f9087315e0cd 100644 --- a/arch/x86/kvm/cpuid.h +++ b/arch/x86/kvm/cpuid.h @@ -88,4 +88,11 @@ static inline bool guest_cpuid_has_x2apic(struct kvm_vcpu *vcpu) return best && (best->ecx & bit(X86_FEATURE_X2APIC)); } +static inline bool guest_cpuid_has_gbpages(struct kvm_vcpu *vcpu) +{ + struct kvm_cpuid_entry2 *best; + + best = kvm_find_cpuid_entry(vcpu, 0x80000001, 0); + return best && (best->edx & bit(X86_FEATURE_GBPAGES)); +} #endif diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 65f2400b8268..931467881da7 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -22,6 +22,7 @@ #include "mmu.h" #include "x86.h" #include "kvm_cache_regs.h" +#include "cpuid.h" #include #include @@ -3516,11 +3517,14 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu, { int maxphyaddr = cpuid_maxphyaddr(vcpu); u64 exb_bit_rsvd = 0; + u64 gbpages_bit_rsvd = 0; context->bad_mt_xwr = 0; if (!context->nx) exb_bit_rsvd = rsvd_bits(63, 63); + if (!guest_cpuid_has_gbpages(vcpu)) + gbpages_bit_rsvd = rsvd_bits(7, 7); switch (context->root_level) { case PT32_ROOT_LEVEL: /* no rsvd bits for 2 level 4K page table entries */ @@ -3557,14 +3561,14 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu, context->rsvd_bits_mask[0][3] = exb_bit_rsvd | rsvd_bits(maxphyaddr, 51) | rsvd_bits(7, 7); context->rsvd_bits_mask[0][2] = exb_bit_rsvd | - rsvd_bits(maxphyaddr, 51) | rsvd_bits(7, 7); + gbpages_bit_rsvd | rsvd_bits(maxphyaddr, 51); context->rsvd_bits_mask[0][1] = exb_bit_rsvd | rsvd_bits(maxphyaddr, 51); context->rsvd_bits_mask[0][0] = exb_bit_rsvd | rsvd_bits(maxphyaddr, 51); context->rsvd_bits_mask[1][3] = context->rsvd_bits_mask[0][3]; context->rsvd_bits_mask[1][2] = exb_bit_rsvd | - rsvd_bits(maxphyaddr, 51) | + gbpages_bit_rsvd | rsvd_bits(maxphyaddr, 51) | rsvd_bits(13, 29); context->rsvd_bits_mask[1][1] = exb_bit_rsvd | rsvd_bits(maxphyaddr, 51) | -- 2.20.1