Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 85fd514e authored by Jim Mattson's avatar Jim Mattson Committed by Radim Krčmář
Browse files

kvm: nVMX: Shadow "high" parts of shadowed 64-bit VMCS fields 



Inconsistencies result from shadowing only accesses to the full
64-bits of a 64-bit VMCS field, but not shadowing accesses to the high
32-bits of the field. The "high" part of a 64-bit field should be
shadowed whenever the full 64-bit field is shadowed.

Signed-off-by: default avatarJim Mattson <jmattson@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 5fa99cbe

arch/x86/kvm/vmx.c

+34 −26
Original line number Diff line number Diff line
@@ -3764,6 +3764,25 @@ static void free_kvm_area(void) 
	}

}



enum vmcs_field_type {

	VMCS_FIELD_TYPE_U16 = 0,

	VMCS_FIELD_TYPE_U64 = 1,

	VMCS_FIELD_TYPE_U32 = 2,

	VMCS_FIELD_TYPE_NATURAL_WIDTH = 3

};



static inline int vmcs_field_type(unsigned long field)

{

	if (0x1 & field)	/* the *_HIGH fields are all 32 bit */

		return VMCS_FIELD_TYPE_U32;

	return (field >> 13) & 0x3 ;

}



static inline int vmcs_field_readonly(unsigned long field)

{

	return (((field >> 10) & 0x3) == 1);

}



static void init_vmcs_shadow_fields(void)

{

	int i, j;
@@ -3789,14 +3808,22 @@ static void init_vmcs_shadow_fields(void) 


	/* shadowed fields guest access without vmexit */

	for (i = 0; i < max_shadow_read_write_fields; i++) {

		clear_bit(shadow_read_write_fields[i],

			  vmx_vmwrite_bitmap);

		clear_bit(shadow_read_write_fields[i],

			  vmx_vmread_bitmap);

		unsigned long field = shadow_read_write_fields[i];



		clear_bit(field, vmx_vmwrite_bitmap);

		clear_bit(field, vmx_vmread_bitmap);

		if (vmcs_field_type(field) == VMCS_FIELD_TYPE_U64) {

			clear_bit(field + 1, vmx_vmwrite_bitmap);

			clear_bit(field + 1, vmx_vmread_bitmap);

		}

	}

	for (i = 0; i < max_shadow_read_only_fields; i++) {

		unsigned long field = shadow_read_only_fields[i];



		clear_bit(field, vmx_vmread_bitmap);

		if (vmcs_field_type(field) == VMCS_FIELD_TYPE_U64)

			clear_bit(field + 1, vmx_vmread_bitmap);

	}

	for (i = 0; i < max_shadow_read_only_fields; i++)

		clear_bit(shadow_read_only_fields[i],

			  vmx_vmread_bitmap);

}



static __init int alloc_kvm_area(void)
@@ -7219,25 +7246,6 @@ static int handle_vmresume(struct kvm_vcpu *vcpu) 
	return nested_vmx_run(vcpu, false);

}



enum vmcs_field_type {

	VMCS_FIELD_TYPE_U16 = 0,

	VMCS_FIELD_TYPE_U64 = 1,

	VMCS_FIELD_TYPE_U32 = 2,

	VMCS_FIELD_TYPE_NATURAL_WIDTH = 3

};



static inline int vmcs_field_type(unsigned long field)

{

	if (0x1 & field)	/* the *_HIGH fields are all 32 bit */

		return VMCS_FIELD_TYPE_U32;

	return (field >> 13) & 0x3 ;

}



static inline int vmcs_field_readonly(unsigned long field)

{

	return (((field >> 10) & 0x3) == 1);

}



/*

 * Read a vmcs12 field. Since these can have varying lengths and we return

 * one type, we chose the biggest type (u64) and zero-extend the return value