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Commit 5777392e authored by Nadav Amit's avatar Nadav Amit Committed by Paolo Bonzini
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KVM: x86: check DR6/7 high-bits are clear only on long-mode 



When the guest sets DR6 and DR7, KVM asserts the high 32-bits are clear, and
otherwise injects a #GP exception. This exception should only be injected only
if running in long-mode.

Signed-off-by: default avatarNadav Amit <namit@cs.technion.ac.il>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 5381417f

arch/x86/kvm/vmx.c

+1 −1
Original line number Diff line number Diff line
@@ -5184,7 +5184,7 @@ static int handle_dr(struct kvm_vcpu *vcpu) 
			return 1;

		kvm_register_write(vcpu, reg, val);

	} else

		if (kvm_set_dr(vcpu, dr, kvm_register_read(vcpu, reg)))

		if (kvm_set_dr(vcpu, dr, kvm_register_readl(vcpu, reg)))

			return 1;



	skip_emulated_instruction(vcpu);

arch/x86/kvm/x86.h

+18 −0
Original line number Diff line number Diff line
@@ -47,6 +47,16 @@ static inline int is_long_mode(struct kvm_vcpu *vcpu) 
#endif

}



static inline bool is_64_bit_mode(struct kvm_vcpu *vcpu)

{

	int cs_db, cs_l;



	if (!is_long_mode(vcpu))

		return false;

	kvm_x86_ops->get_cs_db_l_bits(vcpu, &cs_db, &cs_l);

	return cs_l;

}



static inline bool mmu_is_nested(struct kvm_vcpu *vcpu)

{

	return vcpu->arch.walk_mmu == &vcpu->arch.nested_mmu;
@@ -108,6 +118,14 @@ static inline bool vcpu_match_mmio_gpa(struct kvm_vcpu *vcpu, gpa_t gpa) 
	return false;

}



static inline unsigned long kvm_register_readl(struct kvm_vcpu *vcpu,

					       enum kvm_reg reg)

{

	unsigned long val = kvm_register_read(vcpu, reg);



	return is_64_bit_mode(vcpu) ? val : (u32)val;

}



void kvm_before_handle_nmi(struct kvm_vcpu *vcpu);

void kvm_after_handle_nmi(struct kvm_vcpu *vcpu);

int kvm_inject_realmode_interrupt(struct kvm_vcpu *vcpu, int irq, int inc_eip);