Commit ab510027 authored by Vladimir Murzin's avatar Vladimir Murzin Committed by Catalin Marinas
Browse files

arm64: KVM: Enable Common Not Private translations 



We rely on cpufeature framework to detect and enable CNP so for KVM we
need to patch hyp to set CNP bit just before TTBR0_EL2 gets written.

For the guest we encode CNP bit while building vttbr, so we don't need
to bother with that in a world switch.

Reviewed-by: default avatarJames Morse <james.morse@arm.com>
Acked-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Acked-by: default avatarMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: default avatarVladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent 5ffdfaed

arch/arm/include/asm/kvm_arm.h

+1 −0
Original line number Diff line number Diff line
@@ -161,6 +161,7 @@ 
#else

#define VTTBR_X		(5 - KVM_T0SZ)

#endif

#define VTTBR_CNP_BIT     _AC(1, UL)

#define VTTBR_BADDR_MASK  (((_AC(1, ULL) << (40 - VTTBR_X)) - 1) << VTTBR_X)

#define VTTBR_VMID_SHIFT  _AC(48, ULL)

#define VTTBR_VMID_MASK(size)	(_AT(u64, (1 << size) - 1) << VTTBR_VMID_SHIFT)

arch/arm/include/asm/kvm_mmu.h

+5 −0
Original line number Diff line number Diff line
@@ -355,6 +355,11 @@ static inline int hyp_map_aux_data(void) 


#define kvm_phys_to_vttbr(addr)		(addr)



static inline bool kvm_cpu_has_cnp(void)

{

	return false;

}



#endif	/* !__ASSEMBLY__ */



#endif /* __ARM_KVM_MMU_H__ */

arch/arm64/include/asm/kvm_arm.h

+1 −0
Original line number Diff line number Diff line
@@ -175,6 +175,7 @@ 
#define VTCR_EL2_FLAGS			(VTCR_EL2_COMMON_BITS | VTCR_EL2_TGRAN_FLAGS)

#define VTTBR_X				(VTTBR_X_TGRAN_MAGIC - VTCR_EL2_T0SZ_IPA)



#define VTTBR_CNP_BIT     (UL(1))

#define VTTBR_BADDR_MASK  (((UL(1) << (PHYS_MASK_SHIFT - VTTBR_X)) - 1) << VTTBR_X)

#define VTTBR_VMID_SHIFT  (UL(48))

#define VTTBR_VMID_MASK(size) (_AT(u64, (1 << size) - 1) << VTTBR_VMID_SHIFT)

arch/arm64/include/asm/kvm_mmu.h

+5 −0
Original line number Diff line number Diff line
@@ -517,5 +517,10 @@ static inline int hyp_map_aux_data(void) 


#define kvm_phys_to_vttbr(addr)		phys_to_ttbr(addr)



static inline bool kvm_cpu_has_cnp(void)

{

	return system_supports_cnp();

}



#endif /* __ASSEMBLY__ */

#endif /* __ARM64_KVM_MMU_H__ */

arch/arm64/kvm/hyp-init.S

+3 −0
Original line number Diff line number Diff line
@@ -65,6 +65,9 @@ __do_hyp_init: 
	b.lo	__kvm_handle_stub_hvc



	phys_to_ttbr x4, x0

alternative_if ARM64_HAS_CNP

	orr	x4, x4, #TTBR_CNP_BIT

alternative_else_nop_endif

	msr	ttbr0_el2, x4



	mrs	x4, tcr_el1

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