From mboxrd@z Thu Jan 1 00:00:00 1970 From: alex.shi@linaro.org (Alex Shi) Date: Fri, 9 Mar 2018 17:06:58 +0800 Subject: [PATCH 15/39] arm64: KVM: Use per-CPU vector when BP hardening is enabled In-Reply-To: <20180309090722.26279-1-alex.shi@linaro.org> References: <20180309090722.26279-1-alex.shi@linaro.org> Message-ID: <20180309090722.26279-16-alex.shi@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org From: Marc Zyngier commit 6840bdd73d07 upstream Now that we have per-CPU vectors, let's plug then in the KVM/arm64 code. BTW, lts 4.4 has no feature ARM64_HAS_VIRT_HOST_EXTN, so no change for this. Signed-off-by: Marc Zyngier Signed-off-by: Will Deacon Signed-off-by: Alex Shi --- arch/arm/include/asm/kvm_mmu.h | 10 +++++++++ arch/arm/kvm/arm.c | 8 ++++++- arch/arm64/include/asm/kvm_mmu.h | 36 ++++++++++++++++++++++++++++++++ 3 files changed, 53 insertions(+), 1 deletion(-) diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h index 23d5cad56ddc..9b32b13a91ba 100644 --- a/arch/arm/include/asm/kvm_mmu.h +++ b/arch/arm/include/asm/kvm_mmu.h @@ -272,6 +272,16 @@ static inline void __kvm_extend_hypmap(pgd_t *boot_hyp_pgd, pgd_t *merged_hyp_pgd, unsigned long hyp_idmap_start) { } +static inline void *kvm_get_hyp_vector(void) +{ + return __kvm_hyp_vector; +} + +static inline int kvm_map_vectors(void) +{ + return 0; +} + #endif /* !__ASSEMBLY__ */ #endif /* __ARM_KVM_MMU_H__ */ diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index d7bef2144760..dc8b5943985c 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -967,7 +967,7 @@ static void cpu_init_hyp_mode(void *dummy) pgd_ptr = kvm_mmu_get_httbr(); stack_page = __this_cpu_read(kvm_arm_hyp_stack_page); hyp_stack_ptr = stack_page + PAGE_SIZE; - vector_ptr = (unsigned long)__kvm_hyp_vector; + vector_ptr = (unsigned long)kvm_get_hyp_vector(); __cpu_init_hyp_mode(boot_pgd_ptr, pgd_ptr, hyp_stack_ptr, vector_ptr); @@ -1065,6 +1065,12 @@ static int init_hyp_mode(void) goto out_free_mappings; } + err = kvm_map_vectors(); + if (err) { + kvm_err("Cannot map vectors\n"); + goto out_err; + } + /* * Map the Hyp stack pages */ diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index 819b21a9851c..0b33258cd8ac 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -301,5 +301,41 @@ static inline void __kvm_extend_hypmap(pgd_t *boot_hyp_pgd, merged_hyp_pgd[idmap_idx] = __pgd(__pa(boot_hyp_pgd) | PMD_TYPE_TABLE); } +#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR +#include + +static inline void *kvm_get_hyp_vector(void) +{ + struct bp_hardening_data *data = arm64_get_bp_hardening_data(); + void *vect = __kvm_hyp_vector; + + if (data->fn) { + vect = __bp_harden_hyp_vecs_start + + data->hyp_vectors_slot * SZ_2K; + + vect = lm_alias(vect); + } + + return vect; +} + +static inline int kvm_map_vectors(void) +{ + return create_hyp_mappings(__bp_harden_hyp_vecs_start, + __bp_harden_hyp_vecs_end); +} + +#else +static inline void *kvm_get_hyp_vector(void) +{ + return __kvm_hyp_vector; +} + +static inline int kvm_map_vectors(void) +{ + return 0; +} +#endif + #endif /* __ASSEMBLY__ */ #endif /* __ARM64_KVM_MMU_H__ */ -- 2.16.2.440.gc6284da