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author | Brijesh Singh | 2017-12-04 17:57:34 +0100 |
---|---|---|
committer | Brijesh Singh | 2017-12-04 20:32:30 +0100 |
commit | 70cd94e60c733e3afc18b0e6aab789c13b5571da (patch) | |
tree | c5ebb08e84a3a5a23edf175a9f29c85525ed6695 /arch/x86/kvm/svm.c | |
parent | KVM: SVM: Add KVM_SEV_INIT command (diff) | |
download | kernel-qcow2-linux-70cd94e60c733e3afc18b0e6aab789c13b5571da.tar.gz kernel-qcow2-linux-70cd94e60c733e3afc18b0e6aab789c13b5571da.tar.xz kernel-qcow2-linux-70cd94e60c733e3afc18b0e6aab789c13b5571da.zip |
KVM: SVM: VMRUN should use associated ASID when SEV is enabled
SEV hardware uses ASIDs to associate a memory encryption key with a
guest VM. During guest creation, a SEV VM uses the SEV_CMD_ACTIVATE
command to bind a particular ASID to the guest. Lets make sure that the
VMCB is programmed with the bound ASID before a VMRUN.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Diffstat (limited to 'arch/x86/kvm/svm.c')
-rw-r--r-- | arch/x86/kvm/svm.c | 58 |
1 files changed, 56 insertions, 2 deletions
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 51186107eb22..cdbdc86d7aee 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -213,6 +213,9 @@ struct vcpu_svm { */ struct list_head ir_list; spinlock_t ir_list_lock; + + /* which host CPU was used for running this vcpu */ + unsigned int last_cpu; }; /* @@ -341,6 +344,13 @@ static inline bool sev_guest(struct kvm *kvm) return sev->active; } +static inline int sev_get_asid(struct kvm *kvm) +{ + struct kvm_sev_info *sev = &kvm->arch.sev_info; + + return sev->asid; +} + static inline void mark_all_dirty(struct vmcb *vmcb) { vmcb->control.clean = 0; @@ -551,6 +561,9 @@ struct svm_cpu_data { struct kvm_ldttss_desc *tss_desc; struct page *save_area; + + /* index = sev_asid, value = vmcb pointer */ + struct vmcb **sev_vmcbs; }; static DEFINE_PER_CPU(struct svm_cpu_data *, svm_data); @@ -864,6 +877,7 @@ static void svm_cpu_uninit(int cpu) return; per_cpu(svm_data, raw_smp_processor_id()) = NULL; + kfree(sd->sev_vmcbs); __free_page(sd->save_area); kfree(sd); } @@ -877,11 +891,18 @@ static int svm_cpu_init(int cpu) if (!sd) return -ENOMEM; sd->cpu = cpu; - sd->save_area = alloc_page(GFP_KERNEL); r = -ENOMEM; + sd->save_area = alloc_page(GFP_KERNEL); if (!sd->save_area) goto err_1; + if (svm_sev_enabled()) { + r = -ENOMEM; + sd->sev_vmcbs = kmalloc((max_sev_asid + 1) * sizeof(void *), GFP_KERNEL); + if (!sd->sev_vmcbs) + goto err_1; + } + per_cpu(svm_data, cpu) = sd; return 0; @@ -1498,10 +1519,16 @@ static int avic_init_backing_page(struct kvm_vcpu *vcpu) static void __sev_asid_free(int asid) { - int pos; + struct svm_cpu_data *sd; + int cpu, pos; pos = asid - 1; clear_bit(pos, sev_asid_bitmap); + + for_each_possible_cpu(cpu) { + sd = per_cpu(svm_data, cpu); + sd->sev_vmcbs[pos] = NULL; + } } static void sev_asid_free(struct kvm *kvm) @@ -4466,12 +4493,39 @@ static void reload_tss(struct kvm_vcpu *vcpu) load_TR_desc(); } +static void pre_sev_run(struct vcpu_svm *svm, int cpu) +{ + struct svm_cpu_data *sd = per_cpu(svm_data, cpu); + int asid = sev_get_asid(svm->vcpu.kvm); + + /* Assign the asid allocated with this SEV guest */ + svm->vmcb->control.asid = asid; + + /* + * Flush guest TLB: + * + * 1) when different VMCB for the same ASID is to be run on the same host CPU. + * 2) or this VMCB was executed on different host CPU in previous VMRUNs. + */ + if (sd->sev_vmcbs[asid] == svm->vmcb && + svm->last_cpu == cpu) + return; + + svm->last_cpu = cpu; + sd->sev_vmcbs[asid] = svm->vmcb; + svm->vmcb->control.tlb_ctl = TLB_CONTROL_FLUSH_ASID; + mark_dirty(svm->vmcb, VMCB_ASID); +} + static void pre_svm_run(struct vcpu_svm *svm) { int cpu = raw_smp_processor_id(); struct svm_cpu_data *sd = per_cpu(svm_data, cpu); + if (sev_guest(svm->vcpu.kvm)) + return pre_sev_run(svm, cpu); + /* FIXME: handle wraparound of asid_generation */ if (svm->asid_generation != sd->asid_generation) new_asid(svm, sd); |