From 94f5e8a4642aedb19ca73f534372d7ed65e1c84e Mon Sep 17 00:00:00 2001 From: David Brazdil Date: Wed, 2 Dec 2020 18:41:10 +0000 Subject: [PATCH] KVM: arm64: Create nVHE copy of cpu_logical_map When KVM starts validating host's PSCI requests, it will need to map MPIDR back to the CPU ID. To this end, copy cpu_logical_map into nVHE hyp memory when KVM is initialized. Only copy the information for CPUs that are online at the point of KVM initialization so that KVM rejects CPUs whose features were not checked against the finalized capabilities. Signed-off-by: David Brazdil Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20201202184122.26046-15-dbrazdil@google.com --- arch/arm64/kvm/arm.c | 19 +++++++++++++++++++ arch/arm64/kvm/hyp/nvhe/hyp-smp.c | 16 ++++++++++++++++ 2 files changed, 35 insertions(+) diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index ef519e4..bcd6e5d 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -64,6 +64,8 @@ static bool vgic_present; static DEFINE_PER_CPU(unsigned char, kvm_arm_hardware_enabled); DEFINE_STATIC_KEY_FALSE(userspace_irqchip_in_use); +extern u64 kvm_nvhe_sym(__cpu_logical_map)[NR_CPUS]; + int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu) { return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE; @@ -1506,6 +1508,20 @@ static inline void hyp_cpu_pm_exit(void) } #endif +static void init_cpu_logical_map(void) +{ + unsigned int cpu; + + /* + * Copy the MPIDR <-> logical CPU ID mapping to hyp. + * Only copy the set of online CPUs whose features have been chacked + * against the finalized system capabilities. The hypervisor will not + * allow any other CPUs from the `possible` set to boot. + */ + for_each_online_cpu(cpu) + kvm_nvhe_sym(__cpu_logical_map)[cpu] = cpu_logical_map(cpu); +} + static int init_common_resources(void) { return kvm_set_ipa_limit(); @@ -1684,6 +1700,9 @@ static int init_hyp_mode(void) } } + if (is_protected_kvm_enabled()) + init_cpu_logical_map(); + return 0; out_err: diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-smp.c b/arch/arm64/kvm/hyp/nvhe/hyp-smp.c index 7b0363b..cbab0c6 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp-smp.c +++ b/arch/arm64/kvm/hyp/nvhe/hyp-smp.c @@ -8,6 +8,22 @@ #include #include +/* + * nVHE copy of data structures tracking available CPU cores. + * Only entries for CPUs that were online at KVM init are populated. + * Other CPUs should not be allowed to boot because their features were + * not checked against the finalized system capabilities. + */ +u64 __ro_after_init __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID }; + +u64 cpu_logical_map(unsigned int cpu) +{ + if (cpu >= ARRAY_SIZE(__cpu_logical_map)) + hyp_panic(); + + return __cpu_logical_map[cpu]; +} + unsigned long __hyp_per_cpu_offset(unsigned int cpu) { unsigned long *cpu_base_array; -- 2.7.4