diff options
| author | Marc Zyngier <marc.zyngier@arm.com> | 2018-02-01 11:07:35 +0000 |
|---|---|---|
| committer | Russell King <rmk+kernel@armlinux.org.uk> | 2018-05-31 11:09:03 +0100 |
| commit | 3f7e8e2e1ebda787f156ce46e3f0a9ce2833fa4f (patch) | |
| tree | cb2e36e2ad4908ce0b3daf776c8857a729a0fc31 /arch/arm/include | |
| parent | c44f366ea7c85e1be27d08f2f0880f4120698125 (diff) | |
ARM: KVM: invalidate BTB on guest exit for Cortex-A12/A17
In order to avoid aliasing attacks against the branch predictor,
let's invalidate the BTB on guest exit. This is made complicated
by the fact that we cannot take a branch before invalidating the
BTB.
We only apply this to A12 and A17, which are the only two ARM
cores on which this useful.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Diffstat (limited to 'arch/arm/include')
| -rw-r--r-- | arch/arm/include/asm/kvm_asm.h | 2 | ||||
| -rw-r--r-- | arch/arm/include/asm/kvm_mmu.h | 17 |
2 files changed, 16 insertions, 3 deletions
diff --git a/arch/arm/include/asm/kvm_asm.h b/arch/arm/include/asm/kvm_asm.h index 36dd2962a42d..df24ed48977d 100644 --- a/arch/arm/include/asm/kvm_asm.h +++ b/arch/arm/include/asm/kvm_asm.h @@ -61,8 +61,6 @@ struct kvm_vcpu; extern char __kvm_hyp_init[]; extern char __kvm_hyp_init_end[]; -extern char __kvm_hyp_vector[]; - extern void __kvm_flush_vm_context(void); extern void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa); extern void __kvm_tlb_flush_vmid(struct kvm *kvm); diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h index de1b919404e4..d08ce9c41df4 100644 --- a/arch/arm/include/asm/kvm_mmu.h +++ b/arch/arm/include/asm/kvm_mmu.h @@ -297,7 +297,22 @@ static inline unsigned int kvm_get_vmid_bits(void) static inline void *kvm_get_hyp_vector(void) { - return kvm_ksym_ref(__kvm_hyp_vector); + switch(read_cpuid_part()) { +#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR + case ARM_CPU_PART_CORTEX_A12: + case ARM_CPU_PART_CORTEX_A17: + { + extern char __kvm_hyp_vector_bp_inv[]; + return kvm_ksym_ref(__kvm_hyp_vector_bp_inv); + } + +#endif + default: + { + extern char __kvm_hyp_vector[]; + return kvm_ksym_ref(__kvm_hyp_vector); + } + } } static inline int kvm_map_vectors(void) |