Commit 07cf8aa9 authored by Will Deacon's avatar Will Deacon Committed by Marc Zyngier
Browse files

KVM: arm64: Make BP hardening globals static instead 



Branch predictor hardening of the hyp vectors is partially driven by a
couple of global variables ('__kvm_bp_vect_base' and
'__kvm_harden_el2_vector_slot'). However, these are only used within a
single compilation unit, so internalise them there instead.

Signed-off-by: default avatarWill Deacon <will@kernel.org>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Quentin Perret <qperret@google.com>
Link: https://lore.kernel.org/r/20201113113847.21619-5-will@kernel.org
parent 042c76a9

arch/arm64/include/asm/kvm_mmu.h

+0 −3
Original line number Diff line number Diff line
@@ -208,9 +208,6 @@ static inline int kvm_write_guest_lock(struct kvm *kvm, gpa_t gpa, 
	return ret;

}



extern void *__kvm_bp_vect_base;

extern int __kvm_harden_el2_vector_slot;



#define kvm_phys_to_vttbr(addr)		phys_to_ttbr(addr)



static __always_inline u64 kvm_get_vttbr(struct kvm_s2_mmu *mmu)

arch/arm64/kvm/arm.c

+8 −0
Original line number Diff line number Diff line
@@ -51,6 +51,14 @@ DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector); 
static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page);

unsigned long kvm_arm_hyp_percpu_base[NR_CPUS];



/* Hypervisor VA of the indirect vector trampoline page */

static void *__kvm_bp_vect_base;

/*

 * Slot in the hyp vector page for use by the indirect vector trampoline

 * when mitigation against Spectre-v2 is not required.

 */

static int __kvm_harden_el2_vector_slot;



/* The VMID used in the VTTBR */

static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1);

static u32 kvm_next_vmid;

arch/arm64/kvm/va_layout.c

+0 −3
Original line number Diff line number Diff line
@@ -131,9 +131,6 @@ void __init kvm_update_va_mask(struct alt_instr *alt, 
	}

}



void *__kvm_bp_vect_base;

int __kvm_harden_el2_vector_slot;



void kvm_patch_vector_branch(struct alt_instr *alt,

			     __le32 *origptr, __le32 *updptr, int nr_inst)

{

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