diff options
| author | Marc Zyngier <marc.zyngier@arm.com> | 2018-11-07 11:43:49 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-11-23 08:20:38 +0100 |
| commit | 51836963fa6f41d12a5baff7a01faea2a0ce7d90 (patch) | |
| tree | 0c80e0a5bf2bd241f6f1b7963eb0a69a0b1535d4 /arch/arm/include | |
| parent | 47571a90791114c429eb71d070b168f6bdaf32b6 (diff) | |
ARM: KVM: invalidate BTB on guest exit for Cortex-A12/A17
Commit 3f7e8e2e1ebda787f156ce46e3f0a9ce2833fa4f upstream.
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>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 8ef05381984b..24f3ec7c9fbe 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 e2f05cedaf97..625edef2a54f 100644 --- a/arch/arm/include/asm/kvm_mmu.h +++ b/arch/arm/include/asm/kvm_mmu.h @@ -248,7 +248,22 @@ static inline int kvm_read_guest_lock(struct kvm *kvm, 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) |