1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2012 - Virtual Open Systems and Columbia University
4 * Author: Christoffer Dall <c.dall@virtualopensystems.com>
5 */
6
7 #include <linux/bug.h>
8 #include <linux/cpu_pm.h>
9 #include <linux/errno.h>
10 #include <linux/err.h>
11 #include <linux/kvm_host.h>
12 #include <linux/list.h>
13 #include <linux/module.h>
14 #include <linux/vmalloc.h>
15 #include <linux/fs.h>
16 #include <linux/mman.h>
17 #include <linux/sched.h>
18 #include <linux/kmemleak.h>
19 #include <linux/kvm.h>
20 #include <linux/kvm_irqfd.h>
21 #include <linux/irqbypass.h>
22 #include <linux/sched/stat.h>
23 #include <linux/psci.h>
24 #include <trace/events/kvm.h>
25
26 #define CREATE_TRACE_POINTS
27 #include "trace_arm.h"
28
29 #include <linux/uaccess.h>
30 #include <asm/ptrace.h>
31 #include <asm/mman.h>
32 #include <asm/tlbflush.h>
33 #include <asm/cacheflush.h>
34 #include <asm/cpufeature.h>
35 #include <asm/virt.h>
36 #include <asm/kvm_arm.h>
37 #include <asm/kvm_asm.h>
38 #include <asm/kvm_mmu.h>
39 #include <asm/kvm_pkvm.h>
40 #include <asm/kvm_emulate.h>
41 #include <asm/sections.h>
42
43 #include <kvm/arm_hypercalls.h>
44 #include <kvm/arm_pmu.h>
45 #include <kvm/arm_psci.h>
46
47 static enum kvm_mode kvm_mode = KVM_MODE_DEFAULT;
48 DEFINE_STATIC_KEY_FALSE(kvm_protected_mode_initialized);
49
50 DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector);
51
52 static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page);
53 DECLARE_KVM_NVHE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
54
55 /* The VMID used in the VTTBR */
56 static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1);
57 static u32 kvm_next_vmid;
58 static DEFINE_SPINLOCK(kvm_vmid_lock);
59
60 static bool vgic_present;
61
62 static DEFINE_PER_CPU(unsigned char, kvm_arm_hardware_enabled);
63 DEFINE_STATIC_KEY_FALSE(userspace_irqchip_in_use);
64
kvm_arch_vcpu_should_kick(struct kvm_vcpu * vcpu)65 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
66 {
67 return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
68 }
69
kvm_arch_hardware_setup(void * opaque)70 int kvm_arch_hardware_setup(void *opaque)
71 {
72 return 0;
73 }
74
kvm_arch_check_processor_compat(void * opaque)75 int kvm_arch_check_processor_compat(void *opaque)
76 {
77 return 0;
78 }
79
kvm_vm_ioctl_enable_cap(struct kvm * kvm,struct kvm_enable_cap * cap)80 int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
81 struct kvm_enable_cap *cap)
82 {
83 int r;
84
85 /* Capabilities with flags */
86 switch (cap->cap) {
87 case KVM_CAP_ARM_PROTECTED_VM:
88 return kvm_arm_vm_ioctl_pkvm(kvm, cap);
89 default:
90 if (cap->flags)
91 return -EINVAL;
92 }
93
94 /* Capabilities without flags */
95 switch (cap->cap) {
96 case KVM_CAP_ARM_NISV_TO_USER:
97 if (kvm_vm_is_protected(kvm)) {
98 r = -EINVAL;
99 } else {
100 r = 0;
101 set_bit(KVM_ARCH_FLAG_RETURN_NISV_IO_ABORT_TO_USER,
102 &kvm->arch.flags);
103 }
104 break;
105 case KVM_CAP_ARM_MTE:
106 mutex_lock(&kvm->lock);
107 if (!system_supports_mte() || kvm->created_vcpus) {
108 r = -EINVAL;
109 } else {
110 r = 0;
111 set_bit(KVM_ARCH_FLAG_MTE_ENABLED, &kvm->arch.flags);
112 }
113 mutex_unlock(&kvm->lock);
114 break;
115 default:
116 r = -EINVAL;
117 break;
118 }
119
120 return r;
121 }
122
kvm_arm_default_max_vcpus(void)123 static int kvm_arm_default_max_vcpus(void)
124 {
125 return vgic_present ? kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS;
126 }
127
set_default_spectre(struct kvm * kvm)128 static void set_default_spectre(struct kvm *kvm)
129 {
130 /*
131 * The default is to expose CSV2 == 1 if the HW isn't affected.
132 * Although this is a per-CPU feature, we make it global because
133 * asymmetric systems are just a nuisance.
134 *
135 * Userspace can override this as long as it doesn't promise
136 * the impossible.
137 */
138 if (arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED)
139 kvm->arch.pfr0_csv2 = 1;
140 if (arm64_get_meltdown_state() == SPECTRE_UNAFFECTED)
141 kvm->arch.pfr0_csv3 = 1;
142 }
143
144 /**
145 * kvm_arch_init_vm - initializes a VM data structure
146 * @kvm: pointer to the KVM struct
147 */
kvm_arch_init_vm(struct kvm * kvm,unsigned long type)148 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
149 {
150 int ret;
151
152 if (type & ~KVM_VM_TYPE_MASK)
153 return -EINVAL;
154
155 ret = kvm_share_hyp(kvm, kvm + 1);
156 if (ret)
157 return ret;
158
159 ret = kvm_init_pvm(kvm, type);
160 if (ret)
161 return ret;
162
163 ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu, type);
164 if (ret)
165 return ret;
166
167 kvm_vgic_early_init(kvm);
168
169 /* The maximum number of VCPUs is limited by the host's GIC model */
170 kvm->arch.max_vcpus = kvm_arm_default_max_vcpus();
171
172 set_default_spectre(kvm);
173
174 return ret;
175 }
176
kvm_arch_vcpu_fault(struct kvm_vcpu * vcpu,struct vm_fault * vmf)177 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
178 {
179 return VM_FAULT_SIGBUS;
180 }
181
182 /**
183 * kvm_arch_destroy_vm - destroy the VM data structure
184 * @kvm: pointer to the KVM struct
185 */
kvm_arch_destroy_vm(struct kvm * kvm)186 void kvm_arch_destroy_vm(struct kvm *kvm)
187 {
188 int i;
189
190 bitmap_free(kvm->arch.pmu_filter);
191
192 kvm_vgic_destroy(kvm);
193
194 if (is_protected_kvm_enabled())
195 kvm_shadow_destroy(kvm);
196
197 for (i = 0; i < KVM_MAX_VCPUS; ++i) {
198 if (kvm->vcpus[i]) {
199 kvm_vcpu_destroy(kvm->vcpus[i]);
200 kvm->vcpus[i] = NULL;
201 }
202 }
203 atomic_set(&kvm->online_vcpus, 0);
204
205 kvm_unshare_hyp(kvm, kvm + 1);
206 }
207
kvm_check_extension(struct kvm * kvm,long ext)208 static int kvm_check_extension(struct kvm *kvm, long ext)
209 {
210 int r;
211
212 switch (ext) {
213 case KVM_CAP_IRQCHIP:
214 r = vgic_present;
215 break;
216 case KVM_CAP_IOEVENTFD:
217 case KVM_CAP_DEVICE_CTRL:
218 case KVM_CAP_USER_MEMORY:
219 case KVM_CAP_SYNC_MMU:
220 case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
221 case KVM_CAP_ONE_REG:
222 case KVM_CAP_ARM_PSCI:
223 case KVM_CAP_ARM_PSCI_0_2:
224 case KVM_CAP_READONLY_MEM:
225 case KVM_CAP_MP_STATE:
226 case KVM_CAP_IMMEDIATE_EXIT:
227 case KVM_CAP_VCPU_EVENTS:
228 case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2:
229 case KVM_CAP_ARM_INJECT_EXT_DABT:
230 case KVM_CAP_SET_GUEST_DEBUG:
231 case KVM_CAP_VCPU_ATTRIBUTES:
232 case KVM_CAP_PTP_KVM:
233 r = 1;
234 break;
235 case KVM_CAP_ARM_NISV_TO_USER:
236 r = !kvm || !kvm_vm_is_protected(kvm);
237 break;
238 case KVM_CAP_ARM_SET_DEVICE_ADDR:
239 r = 1;
240 break;
241 case KVM_CAP_NR_VCPUS:
242 /*
243 * ARM64 treats KVM_CAP_NR_CPUS differently from all other
244 * architectures, as it does not always bound it to
245 * KVM_CAP_MAX_VCPUS. It should not matter much because
246 * this is just an advisory value.
247 */
248 r = min_t(unsigned int, num_online_cpus(),
249 kvm_arm_default_max_vcpus());
250 break;
251 case KVM_CAP_MAX_VCPUS:
252 case KVM_CAP_MAX_VCPU_ID:
253 if (kvm)
254 r = kvm->arch.max_vcpus;
255 else
256 r = kvm_arm_default_max_vcpus();
257 break;
258 case KVM_CAP_MSI_DEVID:
259 if (!kvm)
260 r = -EINVAL;
261 else
262 r = kvm->arch.vgic.msis_require_devid;
263 break;
264 case KVM_CAP_ARM_USER_IRQ:
265 /*
266 * 1: EL1_VTIMER, EL1_PTIMER, and PMU.
267 * (bump this number if adding more devices)
268 */
269 r = 1;
270 break;
271 case KVM_CAP_ARM_MTE:
272 r = system_supports_mte();
273 break;
274 case KVM_CAP_STEAL_TIME:
275 r = kvm_arm_pvtime_supported();
276 break;
277 case KVM_CAP_ARM_EL1_32BIT:
278 r = cpus_have_const_cap(ARM64_HAS_32BIT_EL1);
279 break;
280 case KVM_CAP_GUEST_DEBUG_HW_BPS:
281 r = get_num_brps();
282 break;
283 case KVM_CAP_GUEST_DEBUG_HW_WPS:
284 r = get_num_wrps();
285 break;
286 case KVM_CAP_ARM_PMU_V3:
287 r = kvm_arm_support_pmu_v3();
288 break;
289 case KVM_CAP_ARM_INJECT_SERROR_ESR:
290 r = cpus_have_const_cap(ARM64_HAS_RAS_EXTN);
291 break;
292 case KVM_CAP_ARM_VM_IPA_SIZE:
293 r = get_kvm_ipa_limit();
294 break;
295 case KVM_CAP_ARM_SVE:
296 r = system_supports_sve();
297 break;
298 case KVM_CAP_ARM_PTRAUTH_ADDRESS:
299 case KVM_CAP_ARM_PTRAUTH_GENERIC:
300 r = system_has_full_ptr_auth();
301 break;
302 default:
303 r = 0;
304 }
305
306 return r;
307 }
308
309 /*
310 * Checks whether the exctension specified in ext is supported for protected
311 * vms. The capabilities supported by kvm in general are passed in kvm_cap.
312 */
pkvm_check_extension(struct kvm * kvm,long ext,int kvm_cap)313 static int pkvm_check_extension(struct kvm *kvm, long ext, int kvm_cap)
314 {
315 int r;
316
317 switch (ext) {
318 case KVM_CAP_IRQCHIP:
319 case KVM_CAP_ARM_PSCI:
320 case KVM_CAP_ARM_PSCI_0_2:
321 case KVM_CAP_NR_VCPUS:
322 case KVM_CAP_MAX_VCPUS:
323 case KVM_CAP_MAX_VCPU_ID:
324 case KVM_CAP_MSI_DEVID:
325 case KVM_CAP_ARM_VM_IPA_SIZE:
326 r = kvm_cap;
327 break;
328 case KVM_CAP_GUEST_DEBUG_HW_BPS:
329 r = min(kvm_cap, pkvm_get_max_brps());
330 break;
331 case KVM_CAP_GUEST_DEBUG_HW_WPS:
332 r = min(kvm_cap, pkvm_get_max_wrps());
333 break;
334 case KVM_CAP_ARM_PMU_V3:
335 r = kvm_cap && FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_PMUVER),
336 PVM_ID_AA64DFR0_ALLOW);
337 break;
338 case KVM_CAP_ARM_SVE:
339 r = kvm_cap && FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_SVE),
340 PVM_ID_AA64PFR0_RESTRICT_UNSIGNED);
341 break;
342 case KVM_CAP_ARM_PTRAUTH_ADDRESS:
343 r = kvm_cap &&
344 FIELD_GET(ARM64_FEATURE_MASK(ID_AA64ISAR1_API),
345 PVM_ID_AA64ISAR1_ALLOW) &&
346 FIELD_GET(ARM64_FEATURE_MASK(ID_AA64ISAR1_APA),
347 PVM_ID_AA64ISAR1_ALLOW);
348 break;
349 case KVM_CAP_ARM_PTRAUTH_GENERIC:
350 r = kvm_cap &&
351 FIELD_GET(ARM64_FEATURE_MASK(ID_AA64ISAR1_GPI),
352 PVM_ID_AA64ISAR1_ALLOW) &&
353 FIELD_GET(ARM64_FEATURE_MASK(ID_AA64ISAR1_GPA),
354 PVM_ID_AA64ISAR1_ALLOW);
355 break;
356 case KVM_CAP_ARM_PROTECTED_VM:
357 r = 1;
358 break;
359 default:
360 r = 0;
361 break;
362 }
363
364 return r;
365 }
366
kvm_vm_ioctl_check_extension(struct kvm * kvm,long ext)367 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
368 {
369 int r = kvm_check_extension(kvm, ext);
370
371 if (unlikely(kvm && kvm_vm_is_protected(kvm)))
372 r = pkvm_check_extension(kvm, ext, r);
373
374 return r;
375 }
376
kvm_arch_dev_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)377 long kvm_arch_dev_ioctl(struct file *filp,
378 unsigned int ioctl, unsigned long arg)
379 {
380 return -EINVAL;
381 }
382
kvm_arch_alloc_vm(void)383 struct kvm *kvm_arch_alloc_vm(void)
384 {
385 size_t sz = sizeof(struct kvm);
386
387 if (!has_vhe())
388 return kzalloc(sz, GFP_KERNEL_ACCOUNT);
389
390 return __vmalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_HIGHMEM | __GFP_ZERO);
391 }
392
kvm_arch_free_vm(struct kvm * kvm)393 void kvm_arch_free_vm(struct kvm *kvm)
394 {
395 if (!has_vhe())
396 kfree(kvm);
397 else
398 vfree(kvm);
399 }
400
kvm_arch_vcpu_precreate(struct kvm * kvm,unsigned int id)401 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
402 {
403 if (irqchip_in_kernel(kvm) && vgic_initialized(kvm))
404 return -EBUSY;
405
406 if (id >= kvm->arch.max_vcpus)
407 return -EINVAL;
408
409 return 0;
410 }
411
kvm_arch_vcpu_create(struct kvm_vcpu * vcpu)412 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
413 {
414 int err;
415
416 /* Force users to call KVM_ARM_VCPU_INIT */
417 vcpu->arch.target = -1;
418 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
419
420 vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO;
421
422 /* Set up the timer */
423 kvm_timer_vcpu_init(vcpu);
424
425 kvm_pmu_vcpu_init(vcpu);
426
427 kvm_arm_reset_debug_ptr(vcpu);
428
429 kvm_arm_pvtime_vcpu_init(&vcpu->arch);
430
431 vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu;
432
433 err = kvm_vgic_vcpu_init(vcpu);
434 if (err)
435 return err;
436
437 return kvm_share_hyp(vcpu, vcpu + 1);
438 }
439
kvm_arch_vcpu_postcreate(struct kvm_vcpu * vcpu)440 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
441 {
442 }
443
kvm_arch_vcpu_destroy(struct kvm_vcpu * vcpu)444 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
445 {
446 if (vcpu_has_run_once(vcpu) && unlikely(!irqchip_in_kernel(vcpu->kvm)))
447 static_branch_dec(&userspace_irqchip_in_use);
448
449 if (is_protected_kvm_enabled())
450 free_hyp_memcache(&vcpu->arch.pkvm_memcache);
451 else
452 kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
453 kvm_timer_vcpu_terminate(vcpu);
454 kvm_pmu_vcpu_destroy(vcpu);
455
456 kvm_arm_vcpu_destroy(vcpu);
457 }
458
kvm_cpu_has_pending_timer(struct kvm_vcpu * vcpu)459 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
460 {
461 return kvm_timer_is_pending(vcpu);
462 }
463
kvm_arch_vcpu_blocking(struct kvm_vcpu * vcpu)464 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
465 {
466 /*
467 * If we're about to block (most likely because we've just hit a
468 * WFI), we need to sync back the state of the GIC CPU interface
469 * so that we have the latest PMR and group enables. This ensures
470 * that kvm_arch_vcpu_runnable has up-to-date data to decide
471 * whether we have pending interrupts.
472 *
473 * For the same reason, we want to tell GICv4 that we need
474 * doorbells to be signalled, should an interrupt become pending.
475 */
476 preempt_disable();
477 kvm_vgic_put(vcpu, true);
478 preempt_enable();
479 }
480
kvm_arch_vcpu_unblocking(struct kvm_vcpu * vcpu)481 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
482 {
483 preempt_disable();
484 kvm_vgic_load(vcpu);
485 preempt_enable();
486 }
487
kvm_arch_vcpu_load(struct kvm_vcpu * vcpu,int cpu)488 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
489 {
490 struct kvm_s2_mmu *mmu;
491 int *last_ran;
492
493 if (is_protected_kvm_enabled())
494 goto nommu;
495
496 mmu = vcpu->arch.hw_mmu;
497 last_ran = this_cpu_ptr(mmu->last_vcpu_ran);
498
499 /*
500 * We guarantee that both TLBs and I-cache are private to each
501 * vcpu. If detecting that a vcpu from the same VM has
502 * previously run on the same physical CPU, call into the
503 * hypervisor code to nuke the relevant contexts.
504 *
505 * We might get preempted before the vCPU actually runs, but
506 * over-invalidation doesn't affect correctness.
507 */
508 if (*last_ran != vcpu->vcpu_id) {
509 kvm_call_hyp(__kvm_flush_cpu_context, mmu);
510 *last_ran = vcpu->vcpu_id;
511 }
512
513 nommu:
514 vcpu->cpu = cpu;
515
516 kvm_vgic_load(vcpu);
517 kvm_timer_vcpu_load(vcpu);
518 if (has_vhe())
519 kvm_vcpu_load_sysregs_vhe(vcpu);
520 kvm_arch_vcpu_load_fp(vcpu);
521 kvm_vcpu_pmu_restore_guest(vcpu);
522 if (kvm_arm_is_pvtime_enabled(&vcpu->arch))
523 kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu);
524
525 if (single_task_running())
526 vcpu_clear_wfx_traps(vcpu);
527 else
528 vcpu_set_wfx_traps(vcpu);
529
530 if (vcpu_has_ptrauth(vcpu))
531 vcpu_ptrauth_disable(vcpu);
532 kvm_arch_vcpu_load_debug_state_flags(vcpu);
533
534 if (is_protected_kvm_enabled()) {
535 kvm_call_hyp_nvhe(__pkvm_vcpu_load,
536 vcpu->kvm->arch.pkvm.shadow_handle,
537 vcpu->vcpu_idx, vcpu->arch.hcr_el2);
538 kvm_call_hyp(__vgic_v3_restore_vmcr_aprs,
539 &vcpu->arch.vgic_cpu.vgic_v3);
540 }
541 }
542
kvm_arch_vcpu_put(struct kvm_vcpu * vcpu)543 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
544 {
545 if (is_protected_kvm_enabled()) {
546 kvm_call_hyp(__vgic_v3_save_vmcr_aprs,
547 &vcpu->arch.vgic_cpu.vgic_v3);
548 kvm_call_hyp_nvhe(__pkvm_vcpu_put);
549
550 /* __pkvm_vcpu_put implies a sync of the state */
551 if (!kvm_vm_is_protected(vcpu->kvm))
552 vcpu->arch.flags |= KVM_ARM64_PKVM_STATE_DIRTY;
553 }
554
555 kvm_arch_vcpu_put_debug_state_flags(vcpu);
556 kvm_arch_vcpu_put_fp(vcpu);
557 if (has_vhe())
558 kvm_vcpu_put_sysregs_vhe(vcpu);
559 kvm_timer_vcpu_put(vcpu);
560 kvm_vgic_put(vcpu, false);
561 kvm_vcpu_pmu_restore_host(vcpu);
562
563 vcpu->cpu = -1;
564 }
565
vcpu_power_off(struct kvm_vcpu * vcpu)566 static void vcpu_power_off(struct kvm_vcpu *vcpu)
567 {
568 vcpu->arch.power_off = true;
569 kvm_make_request(KVM_REQ_SLEEP, vcpu);
570 kvm_vcpu_kick(vcpu);
571 }
572
kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)573 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
574 struct kvm_mp_state *mp_state)
575 {
576 if (vcpu->arch.power_off)
577 mp_state->mp_state = KVM_MP_STATE_STOPPED;
578 else
579 mp_state->mp_state = KVM_MP_STATE_RUNNABLE;
580
581 return 0;
582 }
583
kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)584 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
585 struct kvm_mp_state *mp_state)
586 {
587 int ret = 0;
588
589 switch (mp_state->mp_state) {
590 case KVM_MP_STATE_RUNNABLE:
591 vcpu->arch.power_off = false;
592 break;
593 case KVM_MP_STATE_STOPPED:
594 vcpu_power_off(vcpu);
595 break;
596 default:
597 ret = -EINVAL;
598 }
599
600 return ret;
601 }
602
603 /**
604 * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled
605 * @v: The VCPU pointer
606 *
607 * If the guest CPU is not waiting for interrupts or an interrupt line is
608 * asserted, the CPU is by definition runnable.
609 */
kvm_arch_vcpu_runnable(struct kvm_vcpu * v)610 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
611 {
612 bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF);
613 return ((irq_lines || kvm_vgic_vcpu_pending_irq(v))
614 && !v->arch.power_off && !v->arch.pause);
615 }
616
kvm_arch_vcpu_in_kernel(struct kvm_vcpu * vcpu)617 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
618 {
619 return vcpu_mode_priv(vcpu);
620 }
621
622 /* Just ensure a guest exit from a particular CPU */
exit_vm_noop(void * info)623 static void exit_vm_noop(void *info)
624 {
625 }
626
force_vm_exit(const cpumask_t * mask)627 void force_vm_exit(const cpumask_t *mask)
628 {
629 preempt_disable();
630 smp_call_function_many(mask, exit_vm_noop, NULL, true);
631 preempt_enable();
632 }
633
634 /**
635 * need_new_vmid_gen - check that the VMID is still valid
636 * @vmid: The VMID to check
637 *
638 * return true if there is a new generation of VMIDs being used
639 *
640 * The hardware supports a limited set of values with the value zero reserved
641 * for the host, so we check if an assigned value belongs to a previous
642 * generation, which requires us to assign a new value. If we're the first to
643 * use a VMID for the new generation, we must flush necessary caches and TLBs
644 * on all CPUs.
645 */
need_new_vmid_gen(struct kvm_vmid * vmid)646 static bool need_new_vmid_gen(struct kvm_vmid *vmid)
647 {
648 u64 current_vmid_gen = atomic64_read(&kvm_vmid_gen);
649 smp_rmb(); /* Orders read of kvm_vmid_gen and kvm->arch.vmid */
650 return unlikely(READ_ONCE(vmid->vmid_gen) != current_vmid_gen);
651 }
652
653 /**
654 * update_vmid - Update the vmid with a valid VMID for the current generation
655 * @vmid: The stage-2 VMID information struct
656 */
update_vmid(struct kvm_vmid * vmid)657 static void update_vmid(struct kvm_vmid *vmid)
658 {
659 if (!need_new_vmid_gen(vmid))
660 return;
661
662 spin_lock(&kvm_vmid_lock);
663
664 /*
665 * We need to re-check the vmid_gen here to ensure that if another vcpu
666 * already allocated a valid vmid for this vm, then this vcpu should
667 * use the same vmid.
668 */
669 if (!need_new_vmid_gen(vmid)) {
670 spin_unlock(&kvm_vmid_lock);
671 return;
672 }
673
674 /* First user of a new VMID generation? */
675 if (unlikely(kvm_next_vmid == 0)) {
676 atomic64_inc(&kvm_vmid_gen);
677 kvm_next_vmid = 1;
678
679 /*
680 * On SMP we know no other CPUs can use this CPU's or each
681 * other's VMID after force_vm_exit returns since the
682 * kvm_vmid_lock blocks them from reentry to the guest.
683 */
684 force_vm_exit(cpu_all_mask);
685 /*
686 * Now broadcast TLB + ICACHE invalidation over the inner
687 * shareable domain to make sure all data structures are
688 * clean.
689 */
690 kvm_call_hyp(__kvm_flush_vm_context);
691 }
692
693 WRITE_ONCE(vmid->vmid, kvm_next_vmid);
694 kvm_next_vmid++;
695 kvm_next_vmid &= (1 << kvm_get_vmid_bits()) - 1;
696
697 smp_wmb();
698 WRITE_ONCE(vmid->vmid_gen, atomic64_read(&kvm_vmid_gen));
699
700 spin_unlock(&kvm_vmid_lock);
701 }
702
kvm_vcpu_initialized(struct kvm_vcpu * vcpu)703 static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu)
704 {
705 return vcpu->arch.target >= 0;
706 }
707
708 /*
709 * Handle both the initialisation that is being done when the vcpu is
710 * run for the first time, as well as the updates that must be
711 * performed each time we get a new thread dealing with this vcpu.
712 */
kvm_arch_vcpu_run_pid_change(struct kvm_vcpu * vcpu)713 int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu)
714 {
715 struct kvm *kvm = vcpu->kvm;
716 int ret;
717
718 if (!kvm_vcpu_initialized(vcpu))
719 return -ENOEXEC;
720
721 if (!kvm_arm_vcpu_is_finalized(vcpu))
722 return -EPERM;
723
724 ret = kvm_arch_vcpu_run_map_fp(vcpu);
725 if (ret)
726 return ret;
727
728 if (likely(vcpu_has_run_once(vcpu)))
729 return 0;
730
731 kvm_arm_vcpu_init_debug(vcpu);
732
733 if (likely(irqchip_in_kernel(kvm))) {
734 /*
735 * Map the VGIC hardware resources before running a vcpu the
736 * first time on this VM.
737 */
738 ret = kvm_vgic_map_resources(kvm);
739 if (ret)
740 return ret;
741 }
742
743 ret = kvm_timer_enable(vcpu);
744 if (ret)
745 return ret;
746
747 ret = kvm_arm_pmu_v3_enable(vcpu);
748 if (ret)
749 return ret;
750
751 if (!irqchip_in_kernel(kvm)) {
752 /*
753 * Tell the rest of the code that there are userspace irqchip
754 * VMs in the wild.
755 */
756 static_branch_inc(&userspace_irqchip_in_use);
757 }
758
759 if (is_protected_kvm_enabled()) {
760 /* Start with the vcpu in a dirty state */
761 if (!kvm_vm_is_protected(vcpu->kvm))
762 vcpu->arch.flags |= KVM_ARM64_PKVM_STATE_DIRTY;
763 ret = create_el2_shadow(kvm);
764 }
765
766 return ret;
767 }
768
kvm_arch_intc_initialized(struct kvm * kvm)769 bool kvm_arch_intc_initialized(struct kvm *kvm)
770 {
771 return vgic_initialized(kvm);
772 }
773
kvm_arm_halt_guest(struct kvm * kvm)774 void kvm_arm_halt_guest(struct kvm *kvm)
775 {
776 int i;
777 struct kvm_vcpu *vcpu;
778
779 kvm_for_each_vcpu(i, vcpu, kvm)
780 vcpu->arch.pause = true;
781 kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP);
782 }
783
kvm_arm_resume_guest(struct kvm * kvm)784 void kvm_arm_resume_guest(struct kvm *kvm)
785 {
786 int i;
787 struct kvm_vcpu *vcpu;
788
789 kvm_for_each_vcpu(i, vcpu, kvm) {
790 vcpu->arch.pause = false;
791 rcuwait_wake_up(kvm_arch_vcpu_get_wait(vcpu));
792 }
793 }
794
vcpu_req_sleep(struct kvm_vcpu * vcpu)795 static void vcpu_req_sleep(struct kvm_vcpu *vcpu)
796 {
797 struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
798
799 rcuwait_wait_event(wait,
800 (!vcpu->arch.power_off) &&(!vcpu->arch.pause),
801 TASK_INTERRUPTIBLE);
802
803 if (vcpu->arch.power_off || vcpu->arch.pause) {
804 /* Awaken to handle a signal, request we sleep again later. */
805 kvm_make_request(KVM_REQ_SLEEP, vcpu);
806 }
807
808 /*
809 * Make sure we will observe a potential reset request if we've
810 * observed a change to the power state. Pairs with the smp_wmb() in
811 * kvm_psci_vcpu_on().
812 */
813 smp_rmb();
814 }
815
check_vcpu_requests(struct kvm_vcpu * vcpu)816 static void check_vcpu_requests(struct kvm_vcpu *vcpu)
817 {
818 if (kvm_request_pending(vcpu)) {
819 if (kvm_check_request(KVM_REQ_SLEEP, vcpu))
820 vcpu_req_sleep(vcpu);
821
822 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
823 kvm_reset_vcpu(vcpu);
824
825 /*
826 * Clear IRQ_PENDING requests that were made to guarantee
827 * that a VCPU sees new virtual interrupts.
828 */
829 kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu);
830
831 if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu))
832 kvm_update_stolen_time(vcpu);
833
834 if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) {
835 /* The distributor enable bits were changed */
836 preempt_disable();
837 vgic_v4_put(vcpu, false);
838 vgic_v4_load(vcpu);
839 preempt_enable();
840 }
841
842 if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu))
843 kvm_pmu_handle_pmcr(vcpu,
844 __vcpu_sys_reg(vcpu, PMCR_EL0));
845 }
846 }
847
vcpu_mode_is_bad_32bit(struct kvm_vcpu * vcpu)848 static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu)
849 {
850 if (likely(!vcpu_mode_is_32bit(vcpu)))
851 return false;
852
853 return !kvm_supports_32bit_el0();
854 }
855
856 /**
857 * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
858 * @vcpu: The VCPU pointer
859 *
860 * This function is called through the VCPU_RUN ioctl called from user space. It
861 * will execute VM code in a loop until the time slice for the process is used
862 * or some emulation is needed from user space in which case the function will
863 * return with return value 0 and with the kvm_run structure filled in with the
864 * required data for the requested emulation.
865 */
kvm_arch_vcpu_ioctl_run(struct kvm_vcpu * vcpu)866 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
867 {
868 struct kvm_run *run = vcpu->run;
869 int ret;
870
871 if (run->exit_reason == KVM_EXIT_MMIO) {
872 ret = kvm_handle_mmio_return(vcpu);
873 if (ret)
874 return ret;
875 }
876
877 vcpu_load(vcpu);
878
879 if (run->immediate_exit) {
880 ret = -EINTR;
881 goto out;
882 }
883
884 kvm_sigset_activate(vcpu);
885
886 ret = 1;
887 run->exit_reason = KVM_EXIT_UNKNOWN;
888 while (ret > 0) {
889 /*
890 * Check conditions before entering the guest
891 */
892 cond_resched();
893
894 update_vmid(&vcpu->arch.hw_mmu->vmid);
895
896 check_vcpu_requests(vcpu);
897
898 /*
899 * Preparing the interrupts to be injected also
900 * involves poking the GIC, which must be done in a
901 * non-preemptible context.
902 */
903 preempt_disable();
904
905 kvm_pmu_flush_hwstate(vcpu);
906
907 local_irq_disable();
908
909 kvm_vgic_flush_hwstate(vcpu);
910
911 /*
912 * Exit if we have a signal pending so that we can deliver the
913 * signal to user space.
914 */
915 if (signal_pending(current)) {
916 ret = -EINTR;
917 run->exit_reason = KVM_EXIT_INTR;
918 ++vcpu->stat.signal_exits;
919 }
920
921 /*
922 * If we're using a userspace irqchip, then check if we need
923 * to tell a userspace irqchip about timer or PMU level
924 * changes and if so, exit to userspace (the actual level
925 * state gets updated in kvm_timer_update_run and
926 * kvm_pmu_update_run below).
927 */
928 if (static_branch_unlikely(&userspace_irqchip_in_use)) {
929 if (kvm_timer_should_notify_user(vcpu) ||
930 kvm_pmu_should_notify_user(vcpu)) {
931 ret = -EINTR;
932 run->exit_reason = KVM_EXIT_INTR;
933 }
934 }
935
936 /*
937 * Ensure we set mode to IN_GUEST_MODE after we disable
938 * interrupts and before the final VCPU requests check.
939 * See the comment in kvm_vcpu_exiting_guest_mode() and
940 * Documentation/virt/kvm/vcpu-requests.rst
941 */
942 smp_store_mb(vcpu->mode, IN_GUEST_MODE);
943
944 if (ret <= 0 || need_new_vmid_gen(&vcpu->arch.hw_mmu->vmid) ||
945 kvm_request_pending(vcpu)) {
946 vcpu->mode = OUTSIDE_GUEST_MODE;
947 isb(); /* Ensure work in x_flush_hwstate is committed */
948 kvm_pmu_sync_hwstate(vcpu);
949 if (static_branch_unlikely(&userspace_irqchip_in_use))
950 kvm_timer_sync_user(vcpu);
951 kvm_vgic_sync_hwstate(vcpu);
952 local_irq_enable();
953 preempt_enable();
954 continue;
955 }
956
957 kvm_arm_setup_debug(vcpu);
958 kvm_arch_vcpu_ctxflush_fp(vcpu);
959
960 /**************************************************************
961 * Enter the guest
962 */
963 trace_kvm_entry(*vcpu_pc(vcpu));
964 guest_enter_irqoff();
965
966 ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu);
967
968 vcpu->mode = OUTSIDE_GUEST_MODE;
969 vcpu->stat.exits++;
970 /*
971 * Back from guest
972 *************************************************************/
973
974 kvm_arm_clear_debug(vcpu);
975
976 /*
977 * We must sync the PMU state before the vgic state so
978 * that the vgic can properly sample the updated state of the
979 * interrupt line.
980 */
981 kvm_pmu_sync_hwstate(vcpu);
982
983 /*
984 * Sync the vgic state before syncing the timer state because
985 * the timer code needs to know if the virtual timer
986 * interrupts are active.
987 */
988 kvm_vgic_sync_hwstate(vcpu);
989
990 /*
991 * Sync the timer hardware state before enabling interrupts as
992 * we don't want vtimer interrupts to race with syncing the
993 * timer virtual interrupt state.
994 */
995 if (static_branch_unlikely(&userspace_irqchip_in_use))
996 kvm_timer_sync_user(vcpu);
997
998 kvm_arch_vcpu_ctxsync_fp(vcpu);
999
1000 /*
1001 * We may have taken a host interrupt in HYP mode (ie
1002 * while executing the guest). This interrupt is still
1003 * pending, as we haven't serviced it yet!
1004 *
1005 * We're now back in SVC mode, with interrupts
1006 * disabled. Enabling the interrupts now will have
1007 * the effect of taking the interrupt again, in SVC
1008 * mode this time.
1009 */
1010 local_irq_enable();
1011
1012 /*
1013 * We do local_irq_enable() before calling guest_exit() so
1014 * that if a timer interrupt hits while running the guest we
1015 * account that tick as being spent in the guest. We enable
1016 * preemption after calling guest_exit() so that if we get
1017 * preempted we make sure ticks after that is not counted as
1018 * guest time.
1019 */
1020 guest_exit();
1021 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
1022
1023 /* Exit types that need handling before we can be preempted */
1024 handle_exit_early(vcpu, ret);
1025
1026 preempt_enable();
1027
1028 /*
1029 * The ARMv8 architecture doesn't give the hypervisor
1030 * a mechanism to prevent a guest from dropping to AArch32 EL0
1031 * if implemented by the CPU. If we spot the guest in such
1032 * state and that we decided it wasn't supposed to do so (like
1033 * with the asymmetric AArch32 case), return to userspace with
1034 * a fatal error.
1035 */
1036 if (vcpu_mode_is_bad_32bit(vcpu)) {
1037 /*
1038 * As we have caught the guest red-handed, decide that
1039 * it isn't fit for purpose anymore by making the vcpu
1040 * invalid. The VMM can try and fix it by issuing a
1041 * KVM_ARM_VCPU_INIT if it really wants to.
1042 */
1043 vcpu->arch.target = -1;
1044 ret = ARM_EXCEPTION_IL;
1045 }
1046
1047 ret = handle_exit(vcpu, ret);
1048 }
1049
1050 /* Tell userspace about in-kernel device output levels */
1051 if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
1052 kvm_timer_update_run(vcpu);
1053 kvm_pmu_update_run(vcpu);
1054 }
1055
1056 kvm_sigset_deactivate(vcpu);
1057
1058 out:
1059 /*
1060 * In the unlikely event that we are returning to userspace
1061 * with pending exceptions or PC adjustment, commit these
1062 * adjustments in order to give userspace a consistent view of
1063 * the vcpu state. Note that this relies on __kvm_adjust_pc()
1064 * being preempt-safe on VHE.
1065 */
1066 if (unlikely(vcpu->arch.flags & (KVM_ARM64_PENDING_EXCEPTION |
1067 KVM_ARM64_INCREMENT_PC)))
1068 kvm_call_hyp(__kvm_adjust_pc, vcpu);
1069
1070 vcpu_put(vcpu);
1071 return ret;
1072 }
1073
vcpu_interrupt_line(struct kvm_vcpu * vcpu,int number,bool level)1074 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level)
1075 {
1076 int bit_index;
1077 bool set;
1078 unsigned long *hcr;
1079
1080 if (number == KVM_ARM_IRQ_CPU_IRQ)
1081 bit_index = __ffs(HCR_VI);
1082 else /* KVM_ARM_IRQ_CPU_FIQ */
1083 bit_index = __ffs(HCR_VF);
1084
1085 hcr = vcpu_hcr(vcpu);
1086 if (level)
1087 set = test_and_set_bit(bit_index, hcr);
1088 else
1089 set = test_and_clear_bit(bit_index, hcr);
1090
1091 /*
1092 * If we didn't change anything, no need to wake up or kick other CPUs
1093 */
1094 if (set == level)
1095 return 0;
1096
1097 /*
1098 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and
1099 * trigger a world-switch round on the running physical CPU to set the
1100 * virtual IRQ/FIQ fields in the HCR appropriately.
1101 */
1102 kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu);
1103 kvm_vcpu_kick(vcpu);
1104
1105 return 0;
1106 }
1107
kvm_vm_ioctl_irq_line(struct kvm * kvm,struct kvm_irq_level * irq_level,bool line_status)1108 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
1109 bool line_status)
1110 {
1111 u32 irq = irq_level->irq;
1112 unsigned int irq_type, vcpu_idx, irq_num;
1113 int nrcpus = atomic_read(&kvm->online_vcpus);
1114 struct kvm_vcpu *vcpu = NULL;
1115 bool level = irq_level->level;
1116
1117 irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK;
1118 vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
1119 vcpu_idx += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1);
1120 irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK;
1121
1122 trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level);
1123
1124 switch (irq_type) {
1125 case KVM_ARM_IRQ_TYPE_CPU:
1126 if (irqchip_in_kernel(kvm))
1127 return -ENXIO;
1128
1129 if (vcpu_idx >= nrcpus)
1130 return -EINVAL;
1131
1132 vcpu = kvm_get_vcpu(kvm, vcpu_idx);
1133 if (!vcpu)
1134 return -EINVAL;
1135
1136 if (irq_num > KVM_ARM_IRQ_CPU_FIQ)
1137 return -EINVAL;
1138
1139 return vcpu_interrupt_line(vcpu, irq_num, level);
1140 case KVM_ARM_IRQ_TYPE_PPI:
1141 if (!irqchip_in_kernel(kvm))
1142 return -ENXIO;
1143
1144 if (vcpu_idx >= nrcpus)
1145 return -EINVAL;
1146
1147 vcpu = kvm_get_vcpu(kvm, vcpu_idx);
1148 if (!vcpu)
1149 return -EINVAL;
1150
1151 if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS)
1152 return -EINVAL;
1153
1154 return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level, NULL);
1155 case KVM_ARM_IRQ_TYPE_SPI:
1156 if (!irqchip_in_kernel(kvm))
1157 return -ENXIO;
1158
1159 if (irq_num < VGIC_NR_PRIVATE_IRQS)
1160 return -EINVAL;
1161
1162 return kvm_vgic_inject_irq(kvm, 0, irq_num, level, NULL);
1163 }
1164
1165 return -EINVAL;
1166 }
1167
kvm_vcpu_set_target(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1168 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
1169 const struct kvm_vcpu_init *init)
1170 {
1171 unsigned int i, ret;
1172 u32 phys_target = kvm_target_cpu();
1173
1174 if (init->target != phys_target)
1175 return -EINVAL;
1176
1177 /*
1178 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must
1179 * use the same target.
1180 */
1181 if (vcpu->arch.target != -1 && vcpu->arch.target != init->target)
1182 return -EINVAL;
1183
1184 /* -ENOENT for unknown features, -EINVAL for invalid combinations. */
1185 for (i = 0; i < sizeof(init->features) * 8; i++) {
1186 bool set = (init->features[i / 32] & (1 << (i % 32)));
1187
1188 if (set && i >= KVM_VCPU_MAX_FEATURES)
1189 return -ENOENT;
1190
1191 /*
1192 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must
1193 * use the same feature set.
1194 */
1195 if (vcpu->arch.target != -1 && i < KVM_VCPU_MAX_FEATURES &&
1196 test_bit(i, vcpu->arch.features) != set)
1197 return -EINVAL;
1198
1199 if (set)
1200 set_bit(i, vcpu->arch.features);
1201 }
1202
1203 vcpu->arch.target = phys_target;
1204
1205 /* Now we know what it is, we can reset it. */
1206 ret = kvm_reset_vcpu(vcpu);
1207 if (ret) {
1208 vcpu->arch.target = -1;
1209 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
1210 }
1211
1212 return ret;
1213 }
1214
kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu * vcpu,struct kvm_vcpu_init * init)1215 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
1216 struct kvm_vcpu_init *init)
1217 {
1218 int ret;
1219
1220 ret = kvm_vcpu_set_target(vcpu, init);
1221 if (ret)
1222 return ret;
1223
1224 /*
1225 * Ensure a rebooted VM will fault in RAM pages and detect if the
1226 * guest MMU is turned off and flush the caches as needed.
1227 *
1228 * S2FWB enforces all memory accesses to RAM being cacheable,
1229 * ensuring that the data side is always coherent. We still
1230 * need to invalidate the I-cache though, as FWB does *not*
1231 * imply CTR_EL0.DIC.
1232 */
1233 if (vcpu_has_run_once(vcpu)) {
1234 if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB))
1235 stage2_unmap_vm(vcpu->kvm);
1236 else
1237 icache_inval_all_pou();
1238 }
1239
1240 vcpu_reset_hcr(vcpu);
1241 vcpu->arch.cptr_el2 = CPTR_EL2_DEFAULT;
1242
1243 /*
1244 * Handle the "start in power-off" case.
1245 */
1246 if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features))
1247 vcpu_power_off(vcpu);
1248 else
1249 vcpu->arch.power_off = false;
1250
1251 return 0;
1252 }
1253
kvm_arm_vcpu_set_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1254 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu,
1255 struct kvm_device_attr *attr)
1256 {
1257 int ret = -ENXIO;
1258
1259 switch (attr->group) {
1260 default:
1261 ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr);
1262 break;
1263 }
1264
1265 return ret;
1266 }
1267
kvm_arm_vcpu_get_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1268 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu,
1269 struct kvm_device_attr *attr)
1270 {
1271 int ret = -ENXIO;
1272
1273 switch (attr->group) {
1274 default:
1275 ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr);
1276 break;
1277 }
1278
1279 return ret;
1280 }
1281
kvm_arm_vcpu_has_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1282 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu,
1283 struct kvm_device_attr *attr)
1284 {
1285 int ret = -ENXIO;
1286
1287 switch (attr->group) {
1288 default:
1289 ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr);
1290 break;
1291 }
1292
1293 return ret;
1294 }
1295
kvm_arm_vcpu_get_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1296 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
1297 struct kvm_vcpu_events *events)
1298 {
1299 memset(events, 0, sizeof(*events));
1300
1301 return __kvm_arm_vcpu_get_events(vcpu, events);
1302 }
1303
kvm_arm_vcpu_set_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1304 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
1305 struct kvm_vcpu_events *events)
1306 {
1307 int i;
1308
1309 /* check whether the reserved field is zero */
1310 for (i = 0; i < ARRAY_SIZE(events->reserved); i++)
1311 if (events->reserved[i])
1312 return -EINVAL;
1313
1314 /* check whether the pad field is zero */
1315 for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++)
1316 if (events->exception.pad[i])
1317 return -EINVAL;
1318
1319 return __kvm_arm_vcpu_set_events(vcpu, events);
1320 }
1321
kvm_arch_vcpu_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1322 long kvm_arch_vcpu_ioctl(struct file *filp,
1323 unsigned int ioctl, unsigned long arg)
1324 {
1325 struct kvm_vcpu *vcpu = filp->private_data;
1326 void __user *argp = (void __user *)arg;
1327 struct kvm_device_attr attr;
1328 long r;
1329
1330 switch (ioctl) {
1331 case KVM_ARM_VCPU_INIT: {
1332 struct kvm_vcpu_init init;
1333
1334 r = -EFAULT;
1335 if (copy_from_user(&init, argp, sizeof(init)))
1336 break;
1337
1338 r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init);
1339 break;
1340 }
1341 case KVM_SET_ONE_REG:
1342 case KVM_GET_ONE_REG: {
1343 struct kvm_one_reg reg;
1344
1345 r = -ENOEXEC;
1346 if (unlikely(!kvm_vcpu_initialized(vcpu)))
1347 break;
1348
1349 r = -EFAULT;
1350 if (copy_from_user(®, argp, sizeof(reg)))
1351 break;
1352
1353 /*
1354 * We could owe a reset due to PSCI. Handle the pending reset
1355 * here to ensure userspace register accesses are ordered after
1356 * the reset.
1357 */
1358 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
1359 kvm_reset_vcpu(vcpu);
1360
1361 if (ioctl == KVM_SET_ONE_REG)
1362 r = kvm_arm_set_reg(vcpu, ®);
1363 else
1364 r = kvm_arm_get_reg(vcpu, ®);
1365 break;
1366 }
1367 case KVM_GET_REG_LIST: {
1368 struct kvm_reg_list __user *user_list = argp;
1369 struct kvm_reg_list reg_list;
1370 unsigned n;
1371
1372 r = -ENOEXEC;
1373 if (unlikely(!kvm_vcpu_initialized(vcpu)))
1374 break;
1375
1376 r = -EPERM;
1377 if (!kvm_arm_vcpu_is_finalized(vcpu))
1378 break;
1379
1380 r = -EFAULT;
1381 if (copy_from_user(®_list, user_list, sizeof(reg_list)))
1382 break;
1383 n = reg_list.n;
1384 reg_list.n = kvm_arm_num_regs(vcpu);
1385 if (copy_to_user(user_list, ®_list, sizeof(reg_list)))
1386 break;
1387 r = -E2BIG;
1388 if (n < reg_list.n)
1389 break;
1390 r = kvm_arm_copy_reg_indices(vcpu, user_list->reg);
1391 break;
1392 }
1393 case KVM_SET_DEVICE_ATTR: {
1394 r = -EFAULT;
1395 if (copy_from_user(&attr, argp, sizeof(attr)))
1396 break;
1397 r = kvm_arm_vcpu_set_attr(vcpu, &attr);
1398 break;
1399 }
1400 case KVM_GET_DEVICE_ATTR: {
1401 r = -EFAULT;
1402 if (copy_from_user(&attr, argp, sizeof(attr)))
1403 break;
1404 r = kvm_arm_vcpu_get_attr(vcpu, &attr);
1405 break;
1406 }
1407 case KVM_HAS_DEVICE_ATTR: {
1408 r = -EFAULT;
1409 if (copy_from_user(&attr, argp, sizeof(attr)))
1410 break;
1411 r = kvm_arm_vcpu_has_attr(vcpu, &attr);
1412 break;
1413 }
1414 case KVM_GET_VCPU_EVENTS: {
1415 struct kvm_vcpu_events events;
1416
1417 if (kvm_arm_vcpu_get_events(vcpu, &events))
1418 return -EINVAL;
1419
1420 if (copy_to_user(argp, &events, sizeof(events)))
1421 return -EFAULT;
1422
1423 return 0;
1424 }
1425 case KVM_SET_VCPU_EVENTS: {
1426 struct kvm_vcpu_events events;
1427
1428 if (copy_from_user(&events, argp, sizeof(events)))
1429 return -EFAULT;
1430
1431 return kvm_arm_vcpu_set_events(vcpu, &events);
1432 }
1433 case KVM_ARM_VCPU_FINALIZE: {
1434 int what;
1435
1436 if (!kvm_vcpu_initialized(vcpu))
1437 return -ENOEXEC;
1438
1439 if (get_user(what, (const int __user *)argp))
1440 return -EFAULT;
1441
1442 return kvm_arm_vcpu_finalize(vcpu, what);
1443 }
1444 default:
1445 r = -EINVAL;
1446 }
1447
1448 return r;
1449 }
1450
kvm_arch_sync_dirty_log(struct kvm * kvm,struct kvm_memory_slot * memslot)1451 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
1452 {
1453
1454 }
1455
kvm_arch_flush_remote_tlbs_memslot(struct kvm * kvm,struct kvm_memory_slot * memslot)1456 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
1457 struct kvm_memory_slot *memslot)
1458 {
1459 kvm_flush_remote_tlbs(kvm);
1460 }
1461
kvm_vm_ioctl_set_device_addr(struct kvm * kvm,struct kvm_arm_device_addr * dev_addr)1462 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
1463 struct kvm_arm_device_addr *dev_addr)
1464 {
1465 unsigned long dev_id, type;
1466
1467 dev_id = (dev_addr->id & KVM_ARM_DEVICE_ID_MASK) >>
1468 KVM_ARM_DEVICE_ID_SHIFT;
1469 type = (dev_addr->id & KVM_ARM_DEVICE_TYPE_MASK) >>
1470 KVM_ARM_DEVICE_TYPE_SHIFT;
1471
1472 switch (dev_id) {
1473 case KVM_ARM_DEVICE_VGIC_V2:
1474 if (!vgic_present)
1475 return -ENXIO;
1476 return kvm_vgic_addr(kvm, type, &dev_addr->addr, true);
1477 default:
1478 return -ENODEV;
1479 }
1480 }
1481
kvm_arch_vm_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1482 long kvm_arch_vm_ioctl(struct file *filp,
1483 unsigned int ioctl, unsigned long arg)
1484 {
1485 struct kvm *kvm = filp->private_data;
1486 void __user *argp = (void __user *)arg;
1487
1488 switch (ioctl) {
1489 case KVM_CREATE_IRQCHIP: {
1490 int ret;
1491 if (!vgic_present)
1492 return -ENXIO;
1493 mutex_lock(&kvm->lock);
1494 ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2);
1495 mutex_unlock(&kvm->lock);
1496 return ret;
1497 }
1498 case KVM_ARM_SET_DEVICE_ADDR: {
1499 struct kvm_arm_device_addr dev_addr;
1500
1501 if (copy_from_user(&dev_addr, argp, sizeof(dev_addr)))
1502 return -EFAULT;
1503 return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr);
1504 }
1505 case KVM_ARM_PREFERRED_TARGET: {
1506 struct kvm_vcpu_init init;
1507
1508 kvm_vcpu_preferred_target(&init);
1509
1510 if (copy_to_user(argp, &init, sizeof(init)))
1511 return -EFAULT;
1512
1513 return 0;
1514 }
1515 case KVM_ARM_MTE_COPY_TAGS: {
1516 struct kvm_arm_copy_mte_tags copy_tags;
1517
1518 if (copy_from_user(©_tags, argp, sizeof(copy_tags)))
1519 return -EFAULT;
1520 return kvm_vm_ioctl_mte_copy_tags(kvm, ©_tags);
1521 }
1522 default:
1523 return -EINVAL;
1524 }
1525 }
1526
nvhe_percpu_size(void)1527 static unsigned long nvhe_percpu_size(void)
1528 {
1529 return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) -
1530 (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start);
1531 }
1532
nvhe_percpu_order(void)1533 static unsigned long nvhe_percpu_order(void)
1534 {
1535 unsigned long size = nvhe_percpu_size();
1536
1537 return size ? get_order(size) : 0;
1538 }
1539
1540 /* A lookup table holding the hypervisor VA for each vector slot */
1541 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS];
1542
kvm_init_vector_slot(void * base,enum arm64_hyp_spectre_vector slot)1543 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot)
1544 {
1545 hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot);
1546 }
1547
kvm_init_vector_slots(void)1548 static int kvm_init_vector_slots(void)
1549 {
1550 int err;
1551 void *base;
1552
1553 base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector));
1554 kvm_init_vector_slot(base, HYP_VECTOR_DIRECT);
1555
1556 base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs));
1557 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT);
1558
1559 if (kvm_system_needs_idmapped_vectors() && !has_vhe()) {
1560 err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs),
1561 __BP_HARDEN_HYP_VECS_SZ, &base);
1562 if (err)
1563 return err;
1564 }
1565
1566 kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT);
1567 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT);
1568 return 0;
1569 }
1570
cpu_prepare_hyp_mode(int cpu)1571 static void cpu_prepare_hyp_mode(int cpu)
1572 {
1573 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
1574 unsigned long tcr;
1575
1576 /*
1577 * Calculate the raw per-cpu offset without a translation from the
1578 * kernel's mapping to the linear mapping, and store it in tpidr_el2
1579 * so that we can use adr_l to access per-cpu variables in EL2.
1580 * Also drop the KASAN tag which gets in the way...
1581 */
1582 params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) -
1583 (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start));
1584
1585 params->mair_el2 = read_sysreg(mair_el1);
1586
1587 /*
1588 * The ID map may be configured to use an extended virtual address
1589 * range. This is only the case if system RAM is out of range for the
1590 * currently configured page size and VA_BITS, in which case we will
1591 * also need the extended virtual range for the HYP ID map, or we won't
1592 * be able to enable the EL2 MMU.
1593 *
1594 * However, at EL2, there is only one TTBR register, and we can't switch
1595 * between translation tables *and* update TCR_EL2.T0SZ at the same
1596 * time. Bottom line: we need to use the extended range with *both* our
1597 * translation tables.
1598 *
1599 * So use the same T0SZ value we use for the ID map.
1600 */
1601 tcr = (read_sysreg(tcr_el1) & TCR_EL2_MASK) | TCR_EL2_RES1;
1602 tcr &= ~TCR_T0SZ_MASK;
1603 tcr |= (idmap_t0sz & GENMASK(TCR_TxSZ_WIDTH - 1, 0)) << TCR_T0SZ_OFFSET;
1604 params->tcr_el2 = tcr;
1605
1606 params->stack_hyp_va = kern_hyp_va(per_cpu(kvm_arm_hyp_stack_page, cpu) + PAGE_SIZE);
1607 params->pgd_pa = kvm_mmu_get_httbr();
1608 if (is_protected_kvm_enabled())
1609 params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS;
1610 else
1611 params->hcr_el2 = HCR_HOST_NVHE_FLAGS;
1612 params->vttbr = params->vtcr = 0;
1613
1614 /*
1615 * Flush the init params from the data cache because the struct will
1616 * be read while the MMU is off.
1617 */
1618 kvm_flush_dcache_to_poc(params, sizeof(*params));
1619 }
1620
hyp_install_host_vector(void)1621 static void hyp_install_host_vector(void)
1622 {
1623 struct kvm_nvhe_init_params *params;
1624 struct arm_smccc_res res;
1625
1626 /* Switch from the HYP stub to our own HYP init vector */
1627 __hyp_set_vectors(kvm_get_idmap_vector());
1628
1629 /*
1630 * Call initialization code, and switch to the full blown HYP code.
1631 * If the cpucaps haven't been finalized yet, something has gone very
1632 * wrong, and hyp will crash and burn when it uses any
1633 * cpus_have_const_cap() wrapper.
1634 */
1635 BUG_ON(!system_capabilities_finalized());
1636 params = this_cpu_ptr_nvhe_sym(kvm_init_params);
1637 arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res);
1638 WARN_ON(res.a0 != SMCCC_RET_SUCCESS);
1639 }
1640
cpu_init_hyp_mode(void)1641 static void cpu_init_hyp_mode(void)
1642 {
1643 hyp_install_host_vector();
1644
1645 /*
1646 * Disabling SSBD on a non-VHE system requires us to enable SSBS
1647 * at EL2.
1648 */
1649 if (this_cpu_has_cap(ARM64_SSBS) &&
1650 arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) {
1651 kvm_call_hyp_nvhe(__kvm_enable_ssbs);
1652 }
1653 }
1654
cpu_hyp_reset(void)1655 static void cpu_hyp_reset(void)
1656 {
1657 if (!is_kernel_in_hyp_mode())
1658 __hyp_reset_vectors();
1659 }
1660
1661 /*
1662 * EL2 vectors can be mapped and rerouted in a number of ways,
1663 * depending on the kernel configuration and CPU present:
1664 *
1665 * - If the CPU is affected by Spectre-v2, the hardening sequence is
1666 * placed in one of the vector slots, which is executed before jumping
1667 * to the real vectors.
1668 *
1669 * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot
1670 * containing the hardening sequence is mapped next to the idmap page,
1671 * and executed before jumping to the real vectors.
1672 *
1673 * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an
1674 * empty slot is selected, mapped next to the idmap page, and
1675 * executed before jumping to the real vectors.
1676 *
1677 * Note that ARM64_SPECTRE_V3A is somewhat incompatible with
1678 * VHE, as we don't have hypervisor-specific mappings. If the system
1679 * is VHE and yet selects this capability, it will be ignored.
1680 */
cpu_set_hyp_vector(void)1681 static void cpu_set_hyp_vector(void)
1682 {
1683 struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data);
1684 void *vector = hyp_spectre_vector_selector[data->slot];
1685
1686 if (!is_protected_kvm_enabled())
1687 *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector;
1688 else
1689 kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot);
1690 }
1691
cpu_hyp_init_context(void)1692 static void cpu_hyp_init_context(void)
1693 {
1694 kvm_init_host_cpu_context(&this_cpu_ptr_hyp_sym(kvm_host_data)->host_ctxt);
1695
1696 if (!is_kernel_in_hyp_mode())
1697 cpu_init_hyp_mode();
1698 }
1699
cpu_hyp_init_features(void)1700 static void cpu_hyp_init_features(void)
1701 {
1702 cpu_set_hyp_vector();
1703 kvm_arm_init_debug();
1704
1705 if (is_kernel_in_hyp_mode())
1706 kvm_timer_init_vhe();
1707
1708 if (vgic_present)
1709 kvm_vgic_init_cpu_hardware();
1710 }
1711
cpu_hyp_reinit(void)1712 static void cpu_hyp_reinit(void)
1713 {
1714 cpu_hyp_reset();
1715 cpu_hyp_init_context();
1716 cpu_hyp_init_features();
1717 }
1718
_kvm_arch_hardware_enable(void * discard)1719 static void _kvm_arch_hardware_enable(void *discard)
1720 {
1721 if (!__this_cpu_read(kvm_arm_hardware_enabled)) {
1722 cpu_hyp_reinit();
1723 __this_cpu_write(kvm_arm_hardware_enabled, 1);
1724 }
1725 }
1726
kvm_arch_hardware_enable(void)1727 int kvm_arch_hardware_enable(void)
1728 {
1729 _kvm_arch_hardware_enable(NULL);
1730 return 0;
1731 }
1732
_kvm_arch_hardware_disable(void * discard)1733 static void _kvm_arch_hardware_disable(void *discard)
1734 {
1735 if (__this_cpu_read(kvm_arm_hardware_enabled)) {
1736 cpu_hyp_reset();
1737 __this_cpu_write(kvm_arm_hardware_enabled, 0);
1738 }
1739 }
1740
kvm_arch_hardware_disable(void)1741 void kvm_arch_hardware_disable(void)
1742 {
1743 if (!is_protected_kvm_enabled())
1744 _kvm_arch_hardware_disable(NULL);
1745 }
1746
1747 #ifdef CONFIG_CPU_PM
hyp_init_cpu_pm_notifier(struct notifier_block * self,unsigned long cmd,void * v)1748 static int hyp_init_cpu_pm_notifier(struct notifier_block *self,
1749 unsigned long cmd,
1750 void *v)
1751 {
1752 /*
1753 * kvm_arm_hardware_enabled is left with its old value over
1754 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should
1755 * re-enable hyp.
1756 */
1757 switch (cmd) {
1758 case CPU_PM_ENTER:
1759 if (__this_cpu_read(kvm_arm_hardware_enabled))
1760 /*
1761 * don't update kvm_arm_hardware_enabled here
1762 * so that the hardware will be re-enabled
1763 * when we resume. See below.
1764 */
1765 cpu_hyp_reset();
1766
1767 return NOTIFY_OK;
1768 case CPU_PM_ENTER_FAILED:
1769 case CPU_PM_EXIT:
1770 if (__this_cpu_read(kvm_arm_hardware_enabled))
1771 /* The hardware was enabled before suspend. */
1772 cpu_hyp_reinit();
1773
1774 return NOTIFY_OK;
1775
1776 default:
1777 return NOTIFY_DONE;
1778 }
1779 }
1780
1781 static struct notifier_block hyp_init_cpu_pm_nb = {
1782 .notifier_call = hyp_init_cpu_pm_notifier,
1783 };
1784
hyp_cpu_pm_init(void)1785 static void hyp_cpu_pm_init(void)
1786 {
1787 if (!is_protected_kvm_enabled())
1788 cpu_pm_register_notifier(&hyp_init_cpu_pm_nb);
1789 }
hyp_cpu_pm_exit(void)1790 static void hyp_cpu_pm_exit(void)
1791 {
1792 if (!is_protected_kvm_enabled())
1793 cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb);
1794 }
1795 #else
hyp_cpu_pm_init(void)1796 static inline void hyp_cpu_pm_init(void)
1797 {
1798 }
hyp_cpu_pm_exit(void)1799 static inline void hyp_cpu_pm_exit(void)
1800 {
1801 }
1802 #endif
1803
init_cpu_logical_map(void)1804 static void init_cpu_logical_map(void)
1805 {
1806 unsigned int cpu;
1807
1808 /*
1809 * Copy the MPIDR <-> logical CPU ID mapping to hyp.
1810 * Only copy the set of online CPUs whose features have been chacked
1811 * against the finalized system capabilities. The hypervisor will not
1812 * allow any other CPUs from the `possible` set to boot.
1813 */
1814 for_each_online_cpu(cpu)
1815 hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu);
1816 }
1817
1818 #define init_psci_0_1_impl_state(config, what) \
1819 config.psci_0_1_ ## what ## _implemented = psci_ops.what
1820
init_psci_relay(void)1821 static bool init_psci_relay(void)
1822 {
1823 /*
1824 * If PSCI has not been initialized, protected KVM cannot install
1825 * itself on newly booted CPUs.
1826 */
1827 if (!psci_ops.get_version) {
1828 kvm_err("Cannot initialize protected mode without PSCI\n");
1829 return false;
1830 }
1831
1832 kvm_host_psci_config.version = psci_ops.get_version();
1833 kvm_host_psci_config.smccc_version = arm_smccc_get_version();
1834
1835 if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) {
1836 kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids();
1837 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend);
1838 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on);
1839 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off);
1840 init_psci_0_1_impl_state(kvm_host_psci_config, migrate);
1841 }
1842 return true;
1843 }
1844
init_subsystems(void)1845 static int init_subsystems(void)
1846 {
1847 int err = 0;
1848
1849 /*
1850 * Enable hardware so that subsystem initialisation can access EL2.
1851 */
1852 on_each_cpu(_kvm_arch_hardware_enable, NULL, 1);
1853
1854 /*
1855 * Register CPU lower-power notifier
1856 */
1857 hyp_cpu_pm_init();
1858
1859 /*
1860 * Init HYP view of VGIC
1861 */
1862 err = kvm_vgic_hyp_init();
1863 switch (err) {
1864 case 0:
1865 vgic_present = true;
1866 break;
1867 case -ENODEV:
1868 case -ENXIO:
1869 vgic_present = false;
1870 err = 0;
1871 break;
1872 default:
1873 goto out;
1874 }
1875
1876 /*
1877 * Init HYP architected timer support
1878 */
1879 err = kvm_timer_hyp_init(vgic_present);
1880 if (err)
1881 goto out;
1882
1883 kvm_perf_init();
1884 kvm_sys_reg_table_init();
1885
1886 out:
1887 if (err || !is_protected_kvm_enabled())
1888 on_each_cpu(_kvm_arch_hardware_disable, NULL, 1);
1889
1890 return err;
1891 }
1892
teardown_hyp_mode(void)1893 static void teardown_hyp_mode(void)
1894 {
1895 int cpu;
1896
1897 free_hyp_pgds();
1898 for_each_possible_cpu(cpu) {
1899 free_page(per_cpu(kvm_arm_hyp_stack_page, cpu));
1900 free_pages(kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu], nvhe_percpu_order());
1901 }
1902 }
1903
do_pkvm_init(u32 hyp_va_bits)1904 static int do_pkvm_init(u32 hyp_va_bits)
1905 {
1906 void *per_cpu_base = kvm_ksym_ref(kvm_nvhe_sym(kvm_arm_hyp_percpu_base));
1907 int ret;
1908
1909 preempt_disable();
1910 cpu_hyp_init_context();
1911 ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size,
1912 num_possible_cpus(), kern_hyp_va(per_cpu_base),
1913 hyp_va_bits);
1914 cpu_hyp_init_features();
1915
1916 /*
1917 * The stub hypercalls are now disabled, so set our local flag to
1918 * prevent a later re-init attempt in kvm_arch_hardware_enable().
1919 */
1920 __this_cpu_write(kvm_arm_hardware_enabled, 1);
1921 preempt_enable();
1922
1923 return ret;
1924 }
1925
kvm_hyp_init_protection(u32 hyp_va_bits)1926 static int kvm_hyp_init_protection(u32 hyp_va_bits)
1927 {
1928 void *addr = phys_to_virt(hyp_mem_base);
1929 int ret;
1930
1931 kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1932 kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1);
1933 kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1);
1934 kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1);
1935 kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
1936 kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
1937 kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1);
1938 kvm_nvhe_sym(__icache_flags) = __icache_flags;
1939 kvm_nvhe_sym(smccc_trng_available) = smccc_trng_available;
1940
1941 ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP);
1942 if (ret)
1943 return ret;
1944
1945 ret = do_pkvm_init(hyp_va_bits);
1946 if (ret)
1947 return ret;
1948
1949 free_hyp_pgds();
1950
1951 return 0;
1952 }
1953
1954 /**
1955 * Inits Hyp-mode on all online CPUs
1956 */
init_hyp_mode(void)1957 static int init_hyp_mode(void)
1958 {
1959 u32 hyp_va_bits;
1960 int cpu;
1961 int err = -ENOMEM;
1962
1963 /*
1964 * The protected Hyp-mode cannot be initialized if the memory pool
1965 * allocation has failed.
1966 */
1967 if (is_protected_kvm_enabled() && !hyp_mem_base)
1968 goto out_err;
1969
1970 /*
1971 * Allocate Hyp PGD and setup Hyp identity mapping
1972 */
1973 err = kvm_mmu_init(&hyp_va_bits);
1974 if (err)
1975 goto out_err;
1976
1977 /*
1978 * Allocate stack pages for Hypervisor-mode
1979 */
1980 for_each_possible_cpu(cpu) {
1981 unsigned long stack_page;
1982
1983 stack_page = __get_free_page(GFP_KERNEL);
1984 if (!stack_page) {
1985 err = -ENOMEM;
1986 goto out_err;
1987 }
1988
1989 per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page;
1990 }
1991
1992 /*
1993 * Allocate and initialize pages for Hypervisor-mode percpu regions.
1994 */
1995 for_each_possible_cpu(cpu) {
1996 struct page *page;
1997 void *page_addr;
1998
1999 page = alloc_pages(GFP_KERNEL, nvhe_percpu_order());
2000 if (!page) {
2001 err = -ENOMEM;
2002 goto out_err;
2003 }
2004
2005 page_addr = page_address(page);
2006 memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size());
2007 kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu] = (unsigned long)page_addr;
2008 }
2009
2010 /*
2011 * Map the Hyp-code called directly from the host
2012 */
2013 err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start),
2014 kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC);
2015 if (err) {
2016 kvm_err("Cannot map world-switch code\n");
2017 goto out_err;
2018 }
2019
2020 err = create_hyp_mappings(kvm_ksym_ref(__hyp_data_start),
2021 kvm_ksym_ref(__hyp_data_end), PAGE_HYP);
2022 if (err) {
2023 kvm_err("Cannot map .hyp.data section\n");
2024 goto out_err;
2025 }
2026
2027 err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start),
2028 kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO);
2029 if (err) {
2030 kvm_err("Cannot map .hyp.rodata section\n");
2031 goto out_err;
2032 }
2033
2034 err = create_hyp_mappings(kvm_ksym_ref(__start_rodata),
2035 kvm_ksym_ref(__end_rodata), PAGE_HYP_RO);
2036 if (err) {
2037 kvm_err("Cannot map rodata section\n");
2038 goto out_err;
2039 }
2040
2041 /*
2042 * .hyp.bss is guaranteed to be placed at the beginning of the .bss
2043 * section thanks to an assertion in the linker script. Map it RW and
2044 * the rest of .bss RO.
2045 */
2046 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start),
2047 kvm_ksym_ref(__hyp_bss_end), PAGE_HYP);
2048 if (err) {
2049 kvm_err("Cannot map hyp bss section: %d\n", err);
2050 goto out_err;
2051 }
2052
2053 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end),
2054 kvm_ksym_ref(__bss_stop), PAGE_HYP_RO);
2055 if (err) {
2056 kvm_err("Cannot map bss section\n");
2057 goto out_err;
2058 }
2059
2060 /*
2061 * Map the Hyp stack pages
2062 */
2063 for_each_possible_cpu(cpu) {
2064 char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu);
2065 err = create_hyp_mappings(stack_page, stack_page + PAGE_SIZE,
2066 PAGE_HYP);
2067
2068 if (err) {
2069 kvm_err("Cannot map hyp stack\n");
2070 goto out_err;
2071 }
2072 }
2073
2074 for_each_possible_cpu(cpu) {
2075 char *percpu_begin = (char *)kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu];
2076 char *percpu_end = percpu_begin + nvhe_percpu_size();
2077
2078 /* Map Hyp percpu pages */
2079 err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP);
2080 if (err) {
2081 kvm_err("Cannot map hyp percpu region\n");
2082 goto out_err;
2083 }
2084
2085 /* Prepare the CPU initialization parameters */
2086 cpu_prepare_hyp_mode(cpu);
2087 }
2088
2089 if (is_protected_kvm_enabled()) {
2090 init_cpu_logical_map();
2091
2092 if (!init_psci_relay()) {
2093 err = -ENODEV;
2094 goto out_err;
2095 }
2096 }
2097
2098 if (is_protected_kvm_enabled()) {
2099 err = kvm_hyp_init_protection(hyp_va_bits);
2100 if (err) {
2101 kvm_err("Failed to init hyp memory protection\n");
2102 goto out_err;
2103 }
2104 }
2105
2106 return 0;
2107
2108 out_err:
2109 teardown_hyp_mode();
2110 kvm_err("error initializing Hyp mode: %d\n", err);
2111 return err;
2112 }
2113
_kvm_host_prot_finalize(void * arg)2114 static void _kvm_host_prot_finalize(void *arg)
2115 {
2116 int *err = arg;
2117
2118 if (WARN_ON(kvm_call_hyp_nvhe(__pkvm_prot_finalize)))
2119 WRITE_ONCE(*err, -EINVAL);
2120 }
2121
pkvm_drop_host_privileges(void)2122 static int pkvm_drop_host_privileges(void)
2123 {
2124 int ret = 0;
2125
2126 /*
2127 * Flip the static key upfront as that may no longer be possible
2128 * once the host stage 2 is installed.
2129 */
2130 static_branch_enable(&kvm_protected_mode_initialized);
2131
2132 /*
2133 * Fixup the boot mode so that we don't take spurious round
2134 * trips via EL2 on cpu_resume. Flush to the PoC for a good
2135 * measure, so that it can be observed by a CPU coming out of
2136 * suspend with the MMU off.
2137 */
2138 __boot_cpu_mode[0] = __boot_cpu_mode[1] = BOOT_CPU_MODE_EL1;
2139 dcache_clean_poc((unsigned long)__boot_cpu_mode,
2140 (unsigned long)(__boot_cpu_mode + 2));
2141
2142 on_each_cpu(_kvm_host_prot_finalize, &ret, 1);
2143 return ret;
2144 }
2145
finalize_hyp_mode(void)2146 static int finalize_hyp_mode(void)
2147 {
2148 if (!is_protected_kvm_enabled())
2149 return 0;
2150
2151 /*
2152 * Exclude HYP BSS and DATA from kmemleak so that they don't get peeked
2153 * at, which would end badly once the sections are inaccessible.
2154 */
2155 kmemleak_free_part(__hyp_bss_start, __hyp_bss_end - __hyp_bss_start);
2156 kmemleak_free_part(__hyp_data_start, __hyp_data_end - __hyp_data_start);
2157 return pkvm_drop_host_privileges();
2158 }
2159
kvm_mpidr_to_vcpu(struct kvm * kvm,unsigned long mpidr)2160 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr)
2161 {
2162 struct kvm_vcpu *vcpu;
2163 int i;
2164
2165 mpidr &= MPIDR_HWID_BITMASK;
2166 kvm_for_each_vcpu(i, vcpu, kvm) {
2167 if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu))
2168 return vcpu;
2169 }
2170 return NULL;
2171 }
2172
kvm_arch_has_irq_bypass(void)2173 bool kvm_arch_has_irq_bypass(void)
2174 {
2175 return true;
2176 }
2177
kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)2178 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
2179 struct irq_bypass_producer *prod)
2180 {
2181 struct kvm_kernel_irqfd *irqfd =
2182 container_of(cons, struct kvm_kernel_irqfd, consumer);
2183
2184 return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq,
2185 &irqfd->irq_entry);
2186 }
kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)2187 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
2188 struct irq_bypass_producer *prod)
2189 {
2190 struct kvm_kernel_irqfd *irqfd =
2191 container_of(cons, struct kvm_kernel_irqfd, consumer);
2192
2193 kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq,
2194 &irqfd->irq_entry);
2195 }
2196
kvm_arch_irq_bypass_stop(struct irq_bypass_consumer * cons)2197 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons)
2198 {
2199 struct kvm_kernel_irqfd *irqfd =
2200 container_of(cons, struct kvm_kernel_irqfd, consumer);
2201
2202 kvm_arm_halt_guest(irqfd->kvm);
2203 }
2204
kvm_arch_irq_bypass_start(struct irq_bypass_consumer * cons)2205 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons)
2206 {
2207 struct kvm_kernel_irqfd *irqfd =
2208 container_of(cons, struct kvm_kernel_irqfd, consumer);
2209
2210 kvm_arm_resume_guest(irqfd->kvm);
2211 }
2212
2213 /**
2214 * Initialize Hyp-mode and memory mappings on all CPUs.
2215 */
kvm_arch_init(void * opaque)2216 int kvm_arch_init(void *opaque)
2217 {
2218 int err;
2219 bool in_hyp_mode;
2220
2221 if (!is_hyp_mode_available()) {
2222 kvm_info("HYP mode not available\n");
2223 return -ENODEV;
2224 }
2225
2226 if (kvm_get_mode() == KVM_MODE_NONE) {
2227 kvm_info("KVM disabled from command line\n");
2228 return -ENODEV;
2229 }
2230
2231 in_hyp_mode = is_kernel_in_hyp_mode();
2232
2233 if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) ||
2234 cpus_have_final_cap(ARM64_WORKAROUND_1508412))
2235 kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \
2236 "Only trusted guests should be used on this system.\n");
2237
2238 err = kvm_set_ipa_limit();
2239 if (err)
2240 return err;
2241
2242 err = kvm_arm_init_sve();
2243 if (err)
2244 return err;
2245
2246 if (!in_hyp_mode) {
2247 err = init_hyp_mode();
2248 if (err)
2249 goto out_err;
2250 }
2251
2252 err = kvm_init_vector_slots();
2253 if (err) {
2254 kvm_err("Cannot initialise vector slots\n");
2255 goto out_hyp;
2256 }
2257
2258 err = init_subsystems();
2259 if (err)
2260 goto out_subs;
2261
2262 if (!in_hyp_mode) {
2263 err = finalize_hyp_mode();
2264 if (err) {
2265 kvm_err("Failed to finalize Hyp protection\n");
2266 goto out_subs;
2267 }
2268 }
2269
2270 if (is_protected_kvm_enabled()) {
2271 kvm_info("Protected nVHE mode initialized successfully\n");
2272 } else if (in_hyp_mode) {
2273 kvm_info("VHE mode initialized successfully\n");
2274 } else {
2275 kvm_info("Hyp mode initialized successfully\n");
2276 }
2277
2278 return 0;
2279
2280 out_subs:
2281 hyp_cpu_pm_exit();
2282 out_hyp:
2283 if (!in_hyp_mode)
2284 teardown_hyp_mode();
2285 out_err:
2286 return err;
2287 }
2288
2289 /* NOP: Compiling as a module not supported */
kvm_arch_exit(void)2290 void kvm_arch_exit(void)
2291 {
2292 kvm_perf_teardown();
2293 }
2294
early_kvm_mode_cfg(char * arg)2295 static int __init early_kvm_mode_cfg(char *arg)
2296 {
2297 if (!arg)
2298 return -EINVAL;
2299
2300 if (strcmp(arg, "none") == 0) {
2301 kvm_mode = KVM_MODE_NONE;
2302 return 0;
2303 }
2304
2305 if (!is_hyp_mode_available()) {
2306 pr_warn_once("KVM is not available. Ignoring kvm-arm.mode\n");
2307 return 0;
2308 }
2309
2310 if (strcmp(arg, "protected") == 0) {
2311 if (!is_kernel_in_hyp_mode())
2312 kvm_mode = KVM_MODE_PROTECTED;
2313 else
2314 pr_warn_once("Protected KVM not available with VHE\n");
2315
2316 return 0;
2317 }
2318
2319 if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) {
2320 kvm_mode = KVM_MODE_DEFAULT;
2321 return 0;
2322 }
2323
2324 return -EINVAL;
2325 }
2326 early_param("kvm-arm.mode", early_kvm_mode_cfg);
2327
kvm_get_mode(void)2328 enum kvm_mode kvm_get_mode(void)
2329 {
2330 return kvm_mode;
2331 }
2332
arm_init(void)2333 static int arm_init(void)
2334 {
2335 int rc = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
2336 return rc;
2337 }
2338
2339 module_init(arm_init);
2340