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/entry-kvm.h>
10 #include <linux/errno.h>
11 #include <linux/err.h>
12 #include <linux/kvm_host.h>
13 #include <linux/list.h>
14 #include <linux/module.h>
15 #include <linux/vmalloc.h>
16 #include <linux/fs.h>
17 #include <linux/mman.h>
18 #include <linux/sched.h>
19 #include <linux/kmemleak.h>
20 #include <linux/kvm.h>
21 #include <linux/kvm_irqfd.h>
22 #include <linux/irqbypass.h>
23 #include <linux/sched/stat.h>
24 #include <linux/psci.h>
25 #include <trace/events/kvm.h>
26
27 #define CREATE_TRACE_POINTS
28 #include "trace_arm.h"
29
30 #include <linux/uaccess.h>
31 #include <asm/ptrace.h>
32 #include <asm/mman.h>
33 #include <asm/tlbflush.h>
34 #include <asm/cacheflush.h>
35 #include <asm/cpufeature.h>
36 #include <asm/virt.h>
37 #include <asm/kvm_arm.h>
38 #include <asm/kvm_asm.h>
39 #include <asm/kvm_mmu.h>
40 #include <asm/kvm_pkvm.h>
41 #include <asm/kvm_emulate.h>
42 #include <asm/sections.h>
43
44 #include <kvm/arm_hypercalls.h>
45 #include <kvm/arm_pmu.h>
46 #include <kvm/arm_psci.h>
47
48 static enum kvm_mode kvm_mode = KVM_MODE_DEFAULT;
49 DEFINE_STATIC_KEY_FALSE(kvm_protected_mode_initialized);
50
51 DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector);
52
53 static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page);
54 DECLARE_KVM_NVHE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
55
56 /* The VMID used in the VTTBR */
57 static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1);
58 static u32 kvm_next_vmid;
59 static DEFINE_SPINLOCK(kvm_vmid_lock);
60
61 static bool vgic_present;
62
63 static DEFINE_PER_CPU(unsigned char, kvm_arm_hardware_enabled);
64 DEFINE_STATIC_KEY_FALSE(userspace_irqchip_in_use);
65
kvm_arch_vcpu_should_kick(struct kvm_vcpu * vcpu)66 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
67 {
68 return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
69 }
70
kvm_arch_hardware_setup(void * opaque)71 int kvm_arch_hardware_setup(void *opaque)
72 {
73 return 0;
74 }
75
kvm_arch_check_processor_compat(void * opaque)76 int kvm_arch_check_processor_compat(void *opaque)
77 {
78 return 0;
79 }
80
kvm_vm_ioctl_enable_cap(struct kvm * kvm,struct kvm_enable_cap * cap)81 int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
82 struct kvm_enable_cap *cap)
83 {
84 int r;
85
86 /* Capabilities with flags */
87 switch (cap->cap) {
88 case KVM_CAP_ARM_PROTECTED_VM:
89 return kvm_arm_vm_ioctl_pkvm(kvm, cap);
90 default:
91 if (cap->flags)
92 return -EINVAL;
93 }
94
95 /* Capabilities without flags */
96 switch (cap->cap) {
97 case KVM_CAP_ARM_NISV_TO_USER:
98 if (kvm_vm_is_protected(kvm)) {
99 r = -EINVAL;
100 } else {
101 r = 0;
102 set_bit(KVM_ARCH_FLAG_RETURN_NISV_IO_ABORT_TO_USER,
103 &kvm->arch.flags);
104 }
105 break;
106 case KVM_CAP_ARM_MTE:
107 mutex_lock(&kvm->lock);
108 if (!system_supports_mte() || kvm->created_vcpus) {
109 r = -EINVAL;
110 } else {
111 r = 0;
112 set_bit(KVM_ARCH_FLAG_MTE_ENABLED, &kvm->arch.flags);
113 }
114 mutex_unlock(&kvm->lock);
115 break;
116 default:
117 r = -EINVAL;
118 break;
119 }
120
121 return r;
122 }
123
kvm_arm_default_max_vcpus(void)124 static int kvm_arm_default_max_vcpus(void)
125 {
126 return vgic_present ? kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS;
127 }
128
set_default_spectre(struct kvm * kvm)129 static void set_default_spectre(struct kvm *kvm)
130 {
131 /*
132 * The default is to expose CSV2 == 1 if the HW isn't affected.
133 * Although this is a per-CPU feature, we make it global because
134 * asymmetric systems are just a nuisance.
135 *
136 * Userspace can override this as long as it doesn't promise
137 * the impossible.
138 */
139 if (arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED)
140 kvm->arch.pfr0_csv2 = 1;
141 if (arm64_get_meltdown_state() == SPECTRE_UNAFFECTED)
142 kvm->arch.pfr0_csv3 = 1;
143 }
144
145 /**
146 * kvm_arch_init_vm - initializes a VM data structure
147 * @kvm: pointer to the KVM struct
148 */
kvm_arch_init_vm(struct kvm * kvm,unsigned long type)149 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
150 {
151 int ret;
152
153 if (type & ~KVM_VM_TYPE_MASK)
154 return -EINVAL;
155
156 ret = kvm_share_hyp(kvm, kvm + 1);
157 if (ret)
158 return ret;
159
160 ret = kvm_init_pvm(kvm, type);
161 if (ret)
162 return ret;
163
164 ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu, type);
165 if (ret)
166 return ret;
167
168 kvm_vgic_early_init(kvm);
169
170 /* The maximum number of VCPUs is limited by the host's GIC model */
171 kvm->arch.max_vcpus = kvm_arm_default_max_vcpus();
172
173 set_default_spectre(kvm);
174
175 return ret;
176 }
177
kvm_arch_vcpu_fault(struct kvm_vcpu * vcpu,struct vm_fault * vmf)178 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
179 {
180 return VM_FAULT_SIGBUS;
181 }
182
183 /**
184 * kvm_arch_destroy_vm - destroy the VM data structure
185 * @kvm: pointer to the KVM struct
186 */
kvm_arch_destroy_vm(struct kvm * kvm)187 void kvm_arch_destroy_vm(struct kvm *kvm)
188 {
189 int i;
190
191 bitmap_free(kvm->arch.pmu_filter);
192
193 kvm_vgic_destroy(kvm);
194
195 if (is_protected_kvm_enabled())
196 kvm_shadow_destroy(kvm);
197
198 for (i = 0; i < KVM_MAX_VCPUS; ++i) {
199 if (kvm->vcpus[i]) {
200 kvm_vcpu_destroy(kvm->vcpus[i]);
201 kvm->vcpus[i] = NULL;
202 }
203 }
204 atomic_set(&kvm->online_vcpus, 0);
205
206 kvm_unshare_hyp(kvm, kvm + 1);
207 }
208
kvm_check_extension(struct kvm * kvm,long ext)209 static int kvm_check_extension(struct kvm *kvm, long ext)
210 {
211 int r;
212
213 switch (ext) {
214 case KVM_CAP_IRQCHIP:
215 r = vgic_present;
216 break;
217 case KVM_CAP_IOEVENTFD:
218 case KVM_CAP_DEVICE_CTRL:
219 case KVM_CAP_USER_MEMORY:
220 case KVM_CAP_SYNC_MMU:
221 case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
222 case KVM_CAP_ONE_REG:
223 case KVM_CAP_ARM_PSCI:
224 case KVM_CAP_ARM_PSCI_0_2:
225 case KVM_CAP_READONLY_MEM:
226 case KVM_CAP_MP_STATE:
227 case KVM_CAP_IMMEDIATE_EXIT:
228 case KVM_CAP_VCPU_EVENTS:
229 case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2:
230 case KVM_CAP_ARM_INJECT_EXT_DABT:
231 case KVM_CAP_SET_GUEST_DEBUG:
232 case KVM_CAP_VCPU_ATTRIBUTES:
233 case KVM_CAP_PTP_KVM:
234 r = 1;
235 break;
236 case KVM_CAP_ARM_NISV_TO_USER:
237 r = !kvm || !kvm_vm_is_protected(kvm);
238 break;
239 case KVM_CAP_SET_GUEST_DEBUG2:
240 return KVM_GUESTDBG_VALID_MASK;
241 case KVM_CAP_ARM_SET_DEVICE_ADDR:
242 r = 1;
243 break;
244 case KVM_CAP_NR_VCPUS:
245 /*
246 * ARM64 treats KVM_CAP_NR_CPUS differently from all other
247 * architectures, as it does not always bound it to
248 * KVM_CAP_MAX_VCPUS. It should not matter much because
249 * this is just an advisory value.
250 */
251 r = min_t(unsigned int, num_online_cpus(),
252 kvm_arm_default_max_vcpus());
253 break;
254 case KVM_CAP_MAX_VCPUS:
255 case KVM_CAP_MAX_VCPU_ID:
256 if (kvm)
257 r = kvm->arch.max_vcpus;
258 else
259 r = kvm_arm_default_max_vcpus();
260 break;
261 case KVM_CAP_MSI_DEVID:
262 if (!kvm)
263 r = -EINVAL;
264 else
265 r = kvm->arch.vgic.msis_require_devid;
266 break;
267 case KVM_CAP_ARM_USER_IRQ:
268 /*
269 * 1: EL1_VTIMER, EL1_PTIMER, and PMU.
270 * (bump this number if adding more devices)
271 */
272 r = 1;
273 break;
274 case KVM_CAP_ARM_MTE:
275 r = system_supports_mte();
276 break;
277 case KVM_CAP_STEAL_TIME:
278 r = kvm_arm_pvtime_supported();
279 break;
280 case KVM_CAP_ARM_EL1_32BIT:
281 r = cpus_have_const_cap(ARM64_HAS_32BIT_EL1);
282 break;
283 case KVM_CAP_GUEST_DEBUG_HW_BPS:
284 r = get_num_brps();
285 break;
286 case KVM_CAP_GUEST_DEBUG_HW_WPS:
287 r = get_num_wrps();
288 break;
289 case KVM_CAP_ARM_PMU_V3:
290 r = kvm_arm_support_pmu_v3();
291 break;
292 case KVM_CAP_ARM_INJECT_SERROR_ESR:
293 r = cpus_have_const_cap(ARM64_HAS_RAS_EXTN);
294 break;
295 case KVM_CAP_ARM_VM_IPA_SIZE:
296 r = get_kvm_ipa_limit();
297 break;
298 case KVM_CAP_ARM_SVE:
299 r = system_supports_sve() && !is_protected_kvm_enabled();
300 break;
301 case KVM_CAP_ARM_PTRAUTH_ADDRESS:
302 case KVM_CAP_ARM_PTRAUTH_GENERIC:
303 r = system_has_full_ptr_auth();
304 break;
305 default:
306 r = 0;
307 }
308
309 return r;
310 }
311
312 /*
313 * Checks whether the exctension specified in ext is supported for protected
314 * vms. The capabilities supported by kvm in general are passed in kvm_cap.
315 */
pkvm_check_extension(struct kvm * kvm,long ext,int kvm_cap)316 static int pkvm_check_extension(struct kvm *kvm, long ext, int kvm_cap)
317 {
318 int r;
319
320 switch (ext) {
321 case KVM_CAP_IRQCHIP:
322 case KVM_CAP_ARM_PSCI:
323 case KVM_CAP_ARM_PSCI_0_2:
324 case KVM_CAP_NR_VCPUS:
325 case KVM_CAP_MAX_VCPUS:
326 case KVM_CAP_MAX_VCPU_ID:
327 case KVM_CAP_MSI_DEVID:
328 case KVM_CAP_ARM_VM_IPA_SIZE:
329 r = kvm_cap;
330 break;
331 case KVM_CAP_GUEST_DEBUG_HW_BPS:
332 r = min(kvm_cap, pkvm_get_max_brps());
333 break;
334 case KVM_CAP_GUEST_DEBUG_HW_WPS:
335 r = min(kvm_cap, pkvm_get_max_wrps());
336 break;
337 case KVM_CAP_ARM_PMU_V3:
338 r = kvm_cap && FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_PMUVER),
339 PVM_ID_AA64DFR0_ALLOW);
340 break;
341 case KVM_CAP_ARM_SVE:
342 r = kvm_cap && FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_SVE),
343 PVM_ID_AA64PFR0_RESTRICT_UNSIGNED);
344 break;
345 case KVM_CAP_ARM_PTRAUTH_ADDRESS:
346 r = kvm_cap &&
347 FIELD_GET(ARM64_FEATURE_MASK(ID_AA64ISAR1_API),
348 PVM_ID_AA64ISAR1_ALLOW) &&
349 FIELD_GET(ARM64_FEATURE_MASK(ID_AA64ISAR1_APA),
350 PVM_ID_AA64ISAR1_ALLOW);
351 break;
352 case KVM_CAP_ARM_PTRAUTH_GENERIC:
353 r = kvm_cap &&
354 FIELD_GET(ARM64_FEATURE_MASK(ID_AA64ISAR1_GPI),
355 PVM_ID_AA64ISAR1_ALLOW) &&
356 FIELD_GET(ARM64_FEATURE_MASK(ID_AA64ISAR1_GPA),
357 PVM_ID_AA64ISAR1_ALLOW);
358 break;
359 case KVM_CAP_ARM_PROTECTED_VM:
360 r = 1;
361 break;
362 default:
363 r = 0;
364 break;
365 }
366
367 return r;
368 }
369
kvm_vm_ioctl_check_extension(struct kvm * kvm,long ext)370 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
371 {
372 int r = kvm_check_extension(kvm, ext);
373
374 if (unlikely(kvm && kvm_vm_is_protected(kvm)))
375 r = pkvm_check_extension(kvm, ext, r);
376
377 return r;
378 }
379
kvm_arch_dev_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)380 long kvm_arch_dev_ioctl(struct file *filp,
381 unsigned int ioctl, unsigned long arg)
382 {
383 return -EINVAL;
384 }
385
kvm_arch_alloc_vm(void)386 struct kvm *kvm_arch_alloc_vm(void)
387 {
388 size_t sz = sizeof(struct kvm);
389
390 if (!has_vhe())
391 return kzalloc(sz, GFP_KERNEL_ACCOUNT);
392
393 return __vmalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_HIGHMEM | __GFP_ZERO);
394 }
395
kvm_arch_free_vm(struct kvm * kvm)396 void kvm_arch_free_vm(struct kvm *kvm)
397 {
398 if (!has_vhe())
399 kfree(kvm);
400 else
401 vfree(kvm);
402 }
403
kvm_arch_vcpu_precreate(struct kvm * kvm,unsigned int id)404 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
405 {
406 if (irqchip_in_kernel(kvm) && vgic_initialized(kvm))
407 return -EBUSY;
408
409 if (id >= kvm->arch.max_vcpus)
410 return -EINVAL;
411
412 return 0;
413 }
414
kvm_arch_vcpu_create(struct kvm_vcpu * vcpu)415 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
416 {
417 int err;
418
419 /* Force users to call KVM_ARM_VCPU_INIT */
420 vcpu->arch.target = -1;
421 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
422
423 vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO;
424
425 /* Set up the timer */
426 kvm_timer_vcpu_init(vcpu);
427
428 kvm_pmu_vcpu_init(vcpu);
429
430 kvm_arm_reset_debug_ptr(vcpu);
431
432 kvm_arm_pvtime_vcpu_init(&vcpu->arch);
433
434 vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu;
435
436 err = kvm_vgic_vcpu_init(vcpu);
437 if (err)
438 return err;
439
440 return kvm_share_hyp(vcpu, vcpu + 1);
441 }
442
kvm_arch_vcpu_postcreate(struct kvm_vcpu * vcpu)443 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
444 {
445 }
446
kvm_arch_vcpu_destroy(struct kvm_vcpu * vcpu)447 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
448 {
449 if (vcpu_has_run_once(vcpu) && unlikely(!irqchip_in_kernel(vcpu->kvm)))
450 static_branch_dec(&userspace_irqchip_in_use);
451
452 if (is_protected_kvm_enabled())
453 free_hyp_memcache(&vcpu->arch.pkvm_memcache);
454 else
455 kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
456 kvm_timer_vcpu_terminate(vcpu);
457 kvm_pmu_vcpu_destroy(vcpu);
458 kvm_vgic_vcpu_destroy(vcpu);
459 kvm_arm_vcpu_destroy(vcpu);
460 }
461
kvm_cpu_has_pending_timer(struct kvm_vcpu * vcpu)462 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
463 {
464 return kvm_timer_is_pending(vcpu);
465 }
466
kvm_arch_vcpu_blocking(struct kvm_vcpu * vcpu)467 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
468 {
469 /*
470 * If we're about to block (most likely because we've just hit a
471 * WFI), we need to sync back the state of the GIC CPU interface
472 * so that we have the latest PMR and group enables. This ensures
473 * that kvm_arch_vcpu_runnable has up-to-date data to decide
474 * whether we have pending interrupts.
475 *
476 * For the same reason, we want to tell GICv4 that we need
477 * doorbells to be signalled, should an interrupt become pending.
478 */
479 preempt_disable();
480 kvm_vgic_put(vcpu, true);
481 preempt_enable();
482 }
483
kvm_arch_vcpu_unblocking(struct kvm_vcpu * vcpu)484 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
485 {
486 preempt_disable();
487 kvm_vgic_load(vcpu);
488 preempt_enable();
489 }
490
kvm_arch_vcpu_load(struct kvm_vcpu * vcpu,int cpu)491 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
492 {
493 struct kvm_s2_mmu *mmu;
494 int *last_ran;
495
496 if (is_protected_kvm_enabled())
497 goto nommu;
498
499 mmu = vcpu->arch.hw_mmu;
500 last_ran = this_cpu_ptr(mmu->last_vcpu_ran);
501
502 /*
503 * We guarantee that both TLBs and I-cache are private to each
504 * vcpu. If detecting that a vcpu from the same VM has
505 * previously run on the same physical CPU, call into the
506 * hypervisor code to nuke the relevant contexts.
507 *
508 * We might get preempted before the vCPU actually runs, but
509 * over-invalidation doesn't affect correctness.
510 */
511 if (*last_ran != vcpu->vcpu_id) {
512 kvm_call_hyp(__kvm_flush_cpu_context, mmu);
513 *last_ran = vcpu->vcpu_id;
514 }
515
516 nommu:
517 vcpu->cpu = cpu;
518
519 kvm_vgic_load(vcpu);
520 kvm_timer_vcpu_load(vcpu);
521 if (has_vhe())
522 kvm_vcpu_load_sysregs_vhe(vcpu);
523 kvm_arch_vcpu_load_fp(vcpu);
524 kvm_vcpu_pmu_restore_guest(vcpu);
525 if (kvm_arm_is_pvtime_enabled(&vcpu->arch))
526 kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu);
527
528 if (single_task_running())
529 vcpu_clear_wfx_traps(vcpu);
530 else
531 vcpu_set_wfx_traps(vcpu);
532
533 if (vcpu_has_ptrauth(vcpu))
534 vcpu_ptrauth_disable(vcpu);
535 kvm_arch_vcpu_load_debug_state_flags(vcpu);
536
537 if (is_protected_kvm_enabled()) {
538 kvm_call_hyp_nvhe(__pkvm_vcpu_load,
539 vcpu->kvm->arch.pkvm.shadow_handle,
540 vcpu->vcpu_idx, vcpu->arch.hcr_el2);
541 kvm_call_hyp(__vgic_v3_restore_vmcr_aprs,
542 &vcpu->arch.vgic_cpu.vgic_v3);
543 }
544 }
545
kvm_arch_vcpu_put(struct kvm_vcpu * vcpu)546 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
547 {
548 if (is_protected_kvm_enabled()) {
549 kvm_call_hyp(__vgic_v3_save_vmcr_aprs,
550 &vcpu->arch.vgic_cpu.vgic_v3);
551 kvm_call_hyp_nvhe(__pkvm_vcpu_put);
552
553 /* __pkvm_vcpu_put implies a sync of the state */
554 if (!kvm_vm_is_protected(vcpu->kvm))
555 vcpu->arch.flags |= KVM_ARM64_PKVM_STATE_DIRTY;
556 }
557
558 kvm_arch_vcpu_put_debug_state_flags(vcpu);
559 kvm_arch_vcpu_put_fp(vcpu);
560 if (has_vhe())
561 kvm_vcpu_put_sysregs_vhe(vcpu);
562 kvm_timer_vcpu_put(vcpu);
563 kvm_vgic_put(vcpu, false);
564 kvm_vcpu_pmu_restore_host(vcpu);
565
566 vcpu->cpu = -1;
567 }
568
vcpu_power_off(struct kvm_vcpu * vcpu)569 static void vcpu_power_off(struct kvm_vcpu *vcpu)
570 {
571 vcpu->arch.power_off = true;
572 kvm_make_request(KVM_REQ_SLEEP, vcpu);
573 kvm_vcpu_kick(vcpu);
574 }
575
kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)576 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
577 struct kvm_mp_state *mp_state)
578 {
579 if (vcpu->arch.power_off)
580 mp_state->mp_state = KVM_MP_STATE_STOPPED;
581 else
582 mp_state->mp_state = KVM_MP_STATE_RUNNABLE;
583
584 return 0;
585 }
586
kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)587 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
588 struct kvm_mp_state *mp_state)
589 {
590 int ret = 0;
591
592 switch (mp_state->mp_state) {
593 case KVM_MP_STATE_RUNNABLE:
594 vcpu->arch.power_off = false;
595 break;
596 case KVM_MP_STATE_STOPPED:
597 vcpu_power_off(vcpu);
598 break;
599 default:
600 ret = -EINVAL;
601 }
602
603 return ret;
604 }
605
606 /**
607 * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled
608 * @v: The VCPU pointer
609 *
610 * If the guest CPU is not waiting for interrupts or an interrupt line is
611 * asserted, the CPU is by definition runnable.
612 */
kvm_arch_vcpu_runnable(struct kvm_vcpu * v)613 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
614 {
615 bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF);
616 return ((irq_lines || kvm_vgic_vcpu_pending_irq(v))
617 && !v->arch.power_off && !v->arch.pause);
618 }
619
kvm_arch_vcpu_in_kernel(struct kvm_vcpu * vcpu)620 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
621 {
622 return vcpu_mode_priv(vcpu);
623 }
624
625 /* Just ensure a guest exit from a particular CPU */
exit_vm_noop(void * info)626 static void exit_vm_noop(void *info)
627 {
628 }
629
force_vm_exit(const cpumask_t * mask)630 void force_vm_exit(const cpumask_t *mask)
631 {
632 preempt_disable();
633 smp_call_function_many(mask, exit_vm_noop, NULL, true);
634 preempt_enable();
635 }
636
637 /**
638 * need_new_vmid_gen - check that the VMID is still valid
639 * @vmid: The VMID to check
640 *
641 * return true if there is a new generation of VMIDs being used
642 *
643 * The hardware supports a limited set of values with the value zero reserved
644 * for the host, so we check if an assigned value belongs to a previous
645 * generation, which requires us to assign a new value. If we're the first to
646 * use a VMID for the new generation, we must flush necessary caches and TLBs
647 * on all CPUs.
648 */
need_new_vmid_gen(struct kvm_vmid * vmid)649 static bool need_new_vmid_gen(struct kvm_vmid *vmid)
650 {
651 u64 current_vmid_gen = atomic64_read(&kvm_vmid_gen);
652 smp_rmb(); /* Orders read of kvm_vmid_gen and kvm->arch.vmid */
653 return unlikely(READ_ONCE(vmid->vmid_gen) != current_vmid_gen);
654 }
655
656 /**
657 * update_vmid - Update the vmid with a valid VMID for the current generation
658 * @vmid: The stage-2 VMID information struct
659 */
update_vmid(struct kvm_vmid * vmid)660 static void update_vmid(struct kvm_vmid *vmid)
661 {
662 if (!need_new_vmid_gen(vmid))
663 return;
664
665 spin_lock(&kvm_vmid_lock);
666
667 /*
668 * We need to re-check the vmid_gen here to ensure that if another vcpu
669 * already allocated a valid vmid for this vm, then this vcpu should
670 * use the same vmid.
671 */
672 if (!need_new_vmid_gen(vmid)) {
673 spin_unlock(&kvm_vmid_lock);
674 return;
675 }
676
677 /* First user of a new VMID generation? */
678 if (unlikely(kvm_next_vmid == 0)) {
679 atomic64_inc(&kvm_vmid_gen);
680 kvm_next_vmid = 1;
681
682 /*
683 * On SMP we know no other CPUs can use this CPU's or each
684 * other's VMID after force_vm_exit returns since the
685 * kvm_vmid_lock blocks them from reentry to the guest.
686 */
687 force_vm_exit(cpu_all_mask);
688 /*
689 * Now broadcast TLB + ICACHE invalidation over the inner
690 * shareable domain to make sure all data structures are
691 * clean.
692 */
693 kvm_call_hyp(__kvm_flush_vm_context);
694 }
695
696 WRITE_ONCE(vmid->vmid, kvm_next_vmid);
697 kvm_next_vmid++;
698 kvm_next_vmid &= (1 << kvm_get_vmid_bits()) - 1;
699
700 smp_wmb();
701 WRITE_ONCE(vmid->vmid_gen, atomic64_read(&kvm_vmid_gen));
702
703 spin_unlock(&kvm_vmid_lock);
704 }
705
kvm_vcpu_initialized(struct kvm_vcpu * vcpu)706 static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu)
707 {
708 return vcpu->arch.target >= 0;
709 }
710
711 /*
712 * Handle both the initialisation that is being done when the vcpu is
713 * run for the first time, as well as the updates that must be
714 * performed each time we get a new thread dealing with this vcpu.
715 */
kvm_arch_vcpu_run_pid_change(struct kvm_vcpu * vcpu)716 int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu)
717 {
718 struct kvm *kvm = vcpu->kvm;
719 int ret;
720
721 if (!kvm_vcpu_initialized(vcpu))
722 return -ENOEXEC;
723
724 if (!kvm_arm_vcpu_is_finalized(vcpu))
725 return -EPERM;
726
727 ret = kvm_arch_vcpu_run_map_fp(vcpu);
728 if (ret)
729 return ret;
730
731 if (likely(vcpu_has_run_once(vcpu)))
732 return 0;
733
734 kvm_arm_vcpu_init_debug(vcpu);
735
736 if (likely(irqchip_in_kernel(kvm))) {
737 /*
738 * Map the VGIC hardware resources before running a vcpu the
739 * first time on this VM.
740 */
741 ret = kvm_vgic_map_resources(kvm);
742 if (ret)
743 return ret;
744 }
745
746 ret = kvm_timer_enable(vcpu);
747 if (ret)
748 return ret;
749
750 ret = kvm_arm_pmu_v3_enable(vcpu);
751 if (ret)
752 return ret;
753
754 if (!irqchip_in_kernel(kvm)) {
755 /*
756 * Tell the rest of the code that there are userspace irqchip
757 * VMs in the wild.
758 */
759 static_branch_inc(&userspace_irqchip_in_use);
760 }
761
762 if (is_protected_kvm_enabled()) {
763 /* Start with the vcpu in a dirty state */
764 if (!kvm_vm_is_protected(vcpu->kvm))
765 vcpu->arch.flags |= KVM_ARM64_PKVM_STATE_DIRTY;
766 ret = create_el2_shadow(kvm);
767 }
768
769 return ret;
770 }
771
kvm_arch_intc_initialized(struct kvm * kvm)772 bool kvm_arch_intc_initialized(struct kvm *kvm)
773 {
774 return vgic_initialized(kvm);
775 }
776
kvm_arm_halt_guest(struct kvm * kvm)777 void kvm_arm_halt_guest(struct kvm *kvm)
778 {
779 int i;
780 struct kvm_vcpu *vcpu;
781
782 kvm_for_each_vcpu(i, vcpu, kvm)
783 vcpu->arch.pause = true;
784 kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP);
785 }
786
kvm_arm_resume_guest(struct kvm * kvm)787 void kvm_arm_resume_guest(struct kvm *kvm)
788 {
789 int i;
790 struct kvm_vcpu *vcpu;
791
792 kvm_for_each_vcpu(i, vcpu, kvm) {
793 vcpu->arch.pause = false;
794 rcuwait_wake_up(kvm_arch_vcpu_get_wait(vcpu));
795 }
796 }
797
vcpu_req_sleep(struct kvm_vcpu * vcpu)798 static void vcpu_req_sleep(struct kvm_vcpu *vcpu)
799 {
800 struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
801
802 rcuwait_wait_event(wait,
803 (!vcpu->arch.power_off) &&(!vcpu->arch.pause),
804 TASK_INTERRUPTIBLE);
805
806 if (vcpu->arch.power_off || vcpu->arch.pause) {
807 /* Awaken to handle a signal, request we sleep again later. */
808 kvm_make_request(KVM_REQ_SLEEP, vcpu);
809 }
810
811 /*
812 * Make sure we will observe a potential reset request if we've
813 * observed a change to the power state. Pairs with the smp_wmb() in
814 * kvm_psci_vcpu_on().
815 */
816 smp_rmb();
817 }
818
check_vcpu_requests(struct kvm_vcpu * vcpu)819 static void check_vcpu_requests(struct kvm_vcpu *vcpu)
820 {
821 if (kvm_request_pending(vcpu)) {
822 if (kvm_check_request(KVM_REQ_SLEEP, vcpu))
823 vcpu_req_sleep(vcpu);
824
825 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
826 kvm_reset_vcpu(vcpu);
827
828 /*
829 * Clear IRQ_PENDING requests that were made to guarantee
830 * that a VCPU sees new virtual interrupts.
831 */
832 kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu);
833
834 if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu))
835 kvm_update_stolen_time(vcpu);
836
837 if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) {
838 /* The distributor enable bits were changed */
839 preempt_disable();
840 vgic_v4_put(vcpu, false);
841 vgic_v4_load(vcpu);
842 preempt_enable();
843 }
844
845 if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu))
846 kvm_pmu_handle_pmcr(vcpu,
847 __vcpu_sys_reg(vcpu, PMCR_EL0));
848 }
849 }
850
vcpu_mode_is_bad_32bit(struct kvm_vcpu * vcpu)851 static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu)
852 {
853 if (likely(!vcpu_mode_is_32bit(vcpu)))
854 return false;
855
856 return !kvm_supports_32bit_el0();
857 }
858
859 /**
860 * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest
861 * @vcpu: The VCPU pointer
862 * @ret: Pointer to write optional return code
863 *
864 * Returns: true if the VCPU needs to return to a preemptible + interruptible
865 * and skip guest entry.
866 *
867 * This function disambiguates between two different types of exits: exits to a
868 * preemptible + interruptible kernel context and exits to userspace. For an
869 * exit to userspace, this function will write the return code to ret and return
870 * true. For an exit to preemptible + interruptible kernel context (i.e. check
871 * for pending work and re-enter), return true without writing to ret.
872 */
kvm_vcpu_exit_request(struct kvm_vcpu * vcpu,int * ret)873 static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret)
874 {
875 struct kvm_run *run = vcpu->run;
876
877 /*
878 * If we're using a userspace irqchip, then check if we need
879 * to tell a userspace irqchip about timer or PMU level
880 * changes and if so, exit to userspace (the actual level
881 * state gets updated in kvm_timer_update_run and
882 * kvm_pmu_update_run below).
883 */
884 if (static_branch_unlikely(&userspace_irqchip_in_use)) {
885 if (kvm_timer_should_notify_user(vcpu) ||
886 kvm_pmu_should_notify_user(vcpu)) {
887 *ret = -EINTR;
888 run->exit_reason = KVM_EXIT_INTR;
889 return true;
890 }
891 }
892
893 return kvm_request_pending(vcpu) ||
894 need_new_vmid_gen(&vcpu->arch.hw_mmu->vmid) ||
895 xfer_to_guest_mode_work_pending();
896 }
897
898 /*
899 * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while
900 * the vCPU is running.
901 *
902 * This must be noinstr as instrumentation may make use of RCU, and this is not
903 * safe during the EQS.
904 */
kvm_arm_vcpu_enter_exit(struct kvm_vcpu * vcpu)905 static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu)
906 {
907 int ret;
908
909 guest_state_enter_irqoff();
910 ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu);
911 guest_state_exit_irqoff();
912
913 return ret;
914 }
915
916 /**
917 * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
918 * @vcpu: The VCPU pointer
919 *
920 * This function is called through the VCPU_RUN ioctl called from user space. It
921 * will execute VM code in a loop until the time slice for the process is used
922 * or some emulation is needed from user space in which case the function will
923 * return with return value 0 and with the kvm_run structure filled in with the
924 * required data for the requested emulation.
925 */
kvm_arch_vcpu_ioctl_run(struct kvm_vcpu * vcpu)926 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
927 {
928 struct kvm_run *run = vcpu->run;
929 int ret;
930
931 if (run->exit_reason == KVM_EXIT_MMIO) {
932 ret = kvm_handle_mmio_return(vcpu);
933 if (ret)
934 return ret;
935 }
936
937 vcpu_load(vcpu);
938
939 if (run->immediate_exit) {
940 ret = -EINTR;
941 goto out;
942 }
943
944 kvm_sigset_activate(vcpu);
945
946 ret = 1;
947 run->exit_reason = KVM_EXIT_UNKNOWN;
948 while (ret > 0) {
949 /*
950 * Check conditions before entering the guest
951 */
952 ret = xfer_to_guest_mode_handle_work(vcpu);
953 if (!ret)
954 ret = 1;
955
956 update_vmid(&vcpu->arch.hw_mmu->vmid);
957
958 check_vcpu_requests(vcpu);
959
960 /*
961 * Preparing the interrupts to be injected also
962 * involves poking the GIC, which must be done in a
963 * non-preemptible context.
964 */
965 preempt_disable();
966
967 kvm_pmu_flush_hwstate(vcpu);
968
969 local_irq_disable();
970
971 kvm_vgic_flush_hwstate(vcpu);
972
973 /*
974 * Ensure we set mode to IN_GUEST_MODE after we disable
975 * interrupts and before the final VCPU requests check.
976 * See the comment in kvm_vcpu_exiting_guest_mode() and
977 * Documentation/virt/kvm/vcpu-requests.rst
978 */
979 smp_store_mb(vcpu->mode, IN_GUEST_MODE);
980
981 if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) {
982 vcpu->mode = OUTSIDE_GUEST_MODE;
983 isb(); /* Ensure work in x_flush_hwstate is committed */
984 kvm_pmu_sync_hwstate(vcpu);
985 if (static_branch_unlikely(&userspace_irqchip_in_use))
986 kvm_timer_sync_user(vcpu);
987 kvm_vgic_sync_hwstate(vcpu);
988 local_irq_enable();
989 preempt_enable();
990 continue;
991 }
992
993 kvm_arm_setup_debug(vcpu);
994 kvm_arch_vcpu_ctxflush_fp(vcpu);
995
996 /**************************************************************
997 * Enter the guest
998 */
999 trace_kvm_entry(*vcpu_pc(vcpu));
1000 guest_timing_enter_irqoff();
1001
1002 ret = kvm_arm_vcpu_enter_exit(vcpu);
1003
1004 vcpu->mode = OUTSIDE_GUEST_MODE;
1005 vcpu->stat.exits++;
1006 /*
1007 * Back from guest
1008 *************************************************************/
1009
1010 kvm_arm_clear_debug(vcpu);
1011
1012 /*
1013 * We must sync the PMU state before the vgic state so
1014 * that the vgic can properly sample the updated state of the
1015 * interrupt line.
1016 */
1017 kvm_pmu_sync_hwstate(vcpu);
1018
1019 /*
1020 * Sync the vgic state before syncing the timer state because
1021 * the timer code needs to know if the virtual timer
1022 * interrupts are active.
1023 */
1024 kvm_vgic_sync_hwstate(vcpu);
1025
1026 /*
1027 * Sync the timer hardware state before enabling interrupts as
1028 * we don't want vtimer interrupts to race with syncing the
1029 * timer virtual interrupt state.
1030 */
1031 if (static_branch_unlikely(&userspace_irqchip_in_use))
1032 kvm_timer_sync_user(vcpu);
1033
1034 kvm_arch_vcpu_ctxsync_fp(vcpu);
1035
1036 /*
1037 * We must ensure that any pending interrupts are taken before
1038 * we exit guest timing so that timer ticks are accounted as
1039 * guest time. Transiently unmask interrupts so that any
1040 * pending interrupts are taken.
1041 *
1042 * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other
1043 * context synchronization event) is necessary to ensure that
1044 * pending interrupts are taken.
1045 */
1046 local_irq_enable();
1047 isb();
1048 local_irq_disable();
1049
1050 guest_timing_exit_irqoff();
1051
1052 local_irq_enable();
1053
1054 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
1055
1056 /* Exit types that need handling before we can be preempted */
1057 handle_exit_early(vcpu, ret);
1058
1059 preempt_enable();
1060
1061 /*
1062 * The ARMv8 architecture doesn't give the hypervisor
1063 * a mechanism to prevent a guest from dropping to AArch32 EL0
1064 * if implemented by the CPU. If we spot the guest in such
1065 * state and that we decided it wasn't supposed to do so (like
1066 * with the asymmetric AArch32 case), return to userspace with
1067 * a fatal error.
1068 */
1069 if (vcpu_mode_is_bad_32bit(vcpu)) {
1070 /*
1071 * As we have caught the guest red-handed, decide that
1072 * it isn't fit for purpose anymore by making the vcpu
1073 * invalid. The VMM can try and fix it by issuing a
1074 * KVM_ARM_VCPU_INIT if it really wants to.
1075 */
1076 vcpu->arch.target = -1;
1077 ret = ARM_EXCEPTION_IL;
1078 }
1079
1080 ret = handle_exit(vcpu, ret);
1081 }
1082
1083 /* Tell userspace about in-kernel device output levels */
1084 if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
1085 kvm_timer_update_run(vcpu);
1086 kvm_pmu_update_run(vcpu);
1087 }
1088
1089 kvm_sigset_deactivate(vcpu);
1090
1091 out:
1092 /*
1093 * In the unlikely event that we are returning to userspace
1094 * with pending exceptions or PC adjustment, commit these
1095 * adjustments in order to give userspace a consistent view of
1096 * the vcpu state. Note that this relies on __kvm_adjust_pc()
1097 * being preempt-safe on VHE.
1098 */
1099 if (unlikely(vcpu->arch.flags & (KVM_ARM64_PENDING_EXCEPTION |
1100 KVM_ARM64_INCREMENT_PC)))
1101 kvm_call_hyp(__kvm_adjust_pc, vcpu);
1102
1103 vcpu_put(vcpu);
1104 return ret;
1105 }
1106
vcpu_interrupt_line(struct kvm_vcpu * vcpu,int number,bool level)1107 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level)
1108 {
1109 int bit_index;
1110 bool set;
1111 unsigned long *hcr;
1112
1113 if (number == KVM_ARM_IRQ_CPU_IRQ)
1114 bit_index = __ffs(HCR_VI);
1115 else /* KVM_ARM_IRQ_CPU_FIQ */
1116 bit_index = __ffs(HCR_VF);
1117
1118 hcr = vcpu_hcr(vcpu);
1119 if (level)
1120 set = test_and_set_bit(bit_index, hcr);
1121 else
1122 set = test_and_clear_bit(bit_index, hcr);
1123
1124 /*
1125 * If we didn't change anything, no need to wake up or kick other CPUs
1126 */
1127 if (set == level)
1128 return 0;
1129
1130 /*
1131 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and
1132 * trigger a world-switch round on the running physical CPU to set the
1133 * virtual IRQ/FIQ fields in the HCR appropriately.
1134 */
1135 kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu);
1136 kvm_vcpu_kick(vcpu);
1137
1138 return 0;
1139 }
1140
kvm_vm_ioctl_irq_line(struct kvm * kvm,struct kvm_irq_level * irq_level,bool line_status)1141 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
1142 bool line_status)
1143 {
1144 u32 irq = irq_level->irq;
1145 unsigned int irq_type, vcpu_idx, irq_num;
1146 int nrcpus = atomic_read(&kvm->online_vcpus);
1147 struct kvm_vcpu *vcpu = NULL;
1148 bool level = irq_level->level;
1149
1150 irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK;
1151 vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
1152 vcpu_idx += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1);
1153 irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK;
1154
1155 trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level);
1156
1157 switch (irq_type) {
1158 case KVM_ARM_IRQ_TYPE_CPU:
1159 if (irqchip_in_kernel(kvm))
1160 return -ENXIO;
1161
1162 if (vcpu_idx >= nrcpus)
1163 return -EINVAL;
1164
1165 vcpu = kvm_get_vcpu(kvm, vcpu_idx);
1166 if (!vcpu)
1167 return -EINVAL;
1168
1169 if (irq_num > KVM_ARM_IRQ_CPU_FIQ)
1170 return -EINVAL;
1171
1172 return vcpu_interrupt_line(vcpu, irq_num, level);
1173 case KVM_ARM_IRQ_TYPE_PPI:
1174 if (!irqchip_in_kernel(kvm))
1175 return -ENXIO;
1176
1177 if (vcpu_idx >= nrcpus)
1178 return -EINVAL;
1179
1180 vcpu = kvm_get_vcpu(kvm, vcpu_idx);
1181 if (!vcpu)
1182 return -EINVAL;
1183
1184 if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS)
1185 return -EINVAL;
1186
1187 return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level, NULL);
1188 case KVM_ARM_IRQ_TYPE_SPI:
1189 if (!irqchip_in_kernel(kvm))
1190 return -ENXIO;
1191
1192 if (irq_num < VGIC_NR_PRIVATE_IRQS)
1193 return -EINVAL;
1194
1195 return kvm_vgic_inject_irq(kvm, 0, irq_num, level, NULL);
1196 }
1197
1198 return -EINVAL;
1199 }
1200
kvm_vcpu_set_target(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1201 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
1202 const struct kvm_vcpu_init *init)
1203 {
1204 unsigned int i, ret;
1205 u32 phys_target = kvm_target_cpu();
1206
1207 if (init->target != phys_target)
1208 return -EINVAL;
1209
1210 /*
1211 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must
1212 * use the same target.
1213 */
1214 if (vcpu->arch.target != -1 && vcpu->arch.target != init->target)
1215 return -EINVAL;
1216
1217 /* -ENOENT for unknown features, -EINVAL for invalid combinations. */
1218 for (i = 0; i < sizeof(init->features) * 8; i++) {
1219 bool set = (init->features[i / 32] & (1 << (i % 32)));
1220
1221 if (set && i >= KVM_VCPU_MAX_FEATURES)
1222 return -ENOENT;
1223
1224 /*
1225 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must
1226 * use the same feature set.
1227 */
1228 if (vcpu->arch.target != -1 && i < KVM_VCPU_MAX_FEATURES &&
1229 test_bit(i, vcpu->arch.features) != set)
1230 return -EINVAL;
1231
1232 if (set)
1233 set_bit(i, vcpu->arch.features);
1234 }
1235
1236 vcpu->arch.target = phys_target;
1237
1238 /* Now we know what it is, we can reset it. */
1239 ret = kvm_reset_vcpu(vcpu);
1240 if (ret) {
1241 vcpu->arch.target = -1;
1242 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
1243 }
1244
1245 return ret;
1246 }
1247
kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu * vcpu,struct kvm_vcpu_init * init)1248 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
1249 struct kvm_vcpu_init *init)
1250 {
1251 int ret;
1252
1253 ret = kvm_vcpu_set_target(vcpu, init);
1254 if (ret)
1255 return ret;
1256
1257 /*
1258 * Ensure a rebooted VM will fault in RAM pages and detect if the
1259 * guest MMU is turned off and flush the caches as needed.
1260 *
1261 * S2FWB enforces all memory accesses to RAM being cacheable,
1262 * ensuring that the data side is always coherent. We still
1263 * need to invalidate the I-cache though, as FWB does *not*
1264 * imply CTR_EL0.DIC.
1265 */
1266 if (vcpu_has_run_once(vcpu)) {
1267 if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB))
1268 stage2_unmap_vm(vcpu->kvm);
1269 else
1270 icache_inval_all_pou();
1271 }
1272
1273 vcpu_reset_hcr(vcpu);
1274 vcpu->arch.cptr_el2 = CPTR_EL2_DEFAULT;
1275
1276 /*
1277 * Handle the "start in power-off" case.
1278 */
1279 if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features))
1280 vcpu_power_off(vcpu);
1281 else
1282 vcpu->arch.power_off = false;
1283
1284 return 0;
1285 }
1286
kvm_arm_vcpu_set_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1287 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu,
1288 struct kvm_device_attr *attr)
1289 {
1290 int ret = -ENXIO;
1291
1292 switch (attr->group) {
1293 default:
1294 ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr);
1295 break;
1296 }
1297
1298 return ret;
1299 }
1300
kvm_arm_vcpu_get_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1301 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu,
1302 struct kvm_device_attr *attr)
1303 {
1304 int ret = -ENXIO;
1305
1306 switch (attr->group) {
1307 default:
1308 ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr);
1309 break;
1310 }
1311
1312 return ret;
1313 }
1314
kvm_arm_vcpu_has_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1315 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu,
1316 struct kvm_device_attr *attr)
1317 {
1318 int ret = -ENXIO;
1319
1320 switch (attr->group) {
1321 default:
1322 ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr);
1323 break;
1324 }
1325
1326 return ret;
1327 }
1328
kvm_arm_vcpu_get_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1329 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
1330 struct kvm_vcpu_events *events)
1331 {
1332 memset(events, 0, sizeof(*events));
1333
1334 return __kvm_arm_vcpu_get_events(vcpu, events);
1335 }
1336
kvm_arm_vcpu_set_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1337 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
1338 struct kvm_vcpu_events *events)
1339 {
1340 int i;
1341
1342 /* check whether the reserved field is zero */
1343 for (i = 0; i < ARRAY_SIZE(events->reserved); i++)
1344 if (events->reserved[i])
1345 return -EINVAL;
1346
1347 /* check whether the pad field is zero */
1348 for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++)
1349 if (events->exception.pad[i])
1350 return -EINVAL;
1351
1352 return __kvm_arm_vcpu_set_events(vcpu, events);
1353 }
1354
kvm_arch_vcpu_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1355 long kvm_arch_vcpu_ioctl(struct file *filp,
1356 unsigned int ioctl, unsigned long arg)
1357 {
1358 struct kvm_vcpu *vcpu = filp->private_data;
1359 void __user *argp = (void __user *)arg;
1360 struct kvm_device_attr attr;
1361 long r;
1362
1363 switch (ioctl) {
1364 case KVM_ARM_VCPU_INIT: {
1365 struct kvm_vcpu_init init;
1366
1367 r = -EFAULT;
1368 if (copy_from_user(&init, argp, sizeof(init)))
1369 break;
1370
1371 r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init);
1372 break;
1373 }
1374 case KVM_SET_ONE_REG:
1375 case KVM_GET_ONE_REG: {
1376 struct kvm_one_reg reg;
1377
1378 r = -ENOEXEC;
1379 if (unlikely(!kvm_vcpu_initialized(vcpu)))
1380 break;
1381
1382 r = -EFAULT;
1383 if (copy_from_user(®, argp, sizeof(reg)))
1384 break;
1385
1386 /*
1387 * We could owe a reset due to PSCI. Handle the pending reset
1388 * here to ensure userspace register accesses are ordered after
1389 * the reset.
1390 */
1391 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
1392 kvm_reset_vcpu(vcpu);
1393
1394 if (ioctl == KVM_SET_ONE_REG)
1395 r = kvm_arm_set_reg(vcpu, ®);
1396 else
1397 r = kvm_arm_get_reg(vcpu, ®);
1398 break;
1399 }
1400 case KVM_GET_REG_LIST: {
1401 struct kvm_reg_list __user *user_list = argp;
1402 struct kvm_reg_list reg_list;
1403 unsigned n;
1404
1405 r = -ENOEXEC;
1406 if (unlikely(!kvm_vcpu_initialized(vcpu)))
1407 break;
1408
1409 r = -EPERM;
1410 if (!kvm_arm_vcpu_is_finalized(vcpu))
1411 break;
1412
1413 r = -EFAULT;
1414 if (copy_from_user(®_list, user_list, sizeof(reg_list)))
1415 break;
1416 n = reg_list.n;
1417 reg_list.n = kvm_arm_num_regs(vcpu);
1418 if (copy_to_user(user_list, ®_list, sizeof(reg_list)))
1419 break;
1420 r = -E2BIG;
1421 if (n < reg_list.n)
1422 break;
1423 r = kvm_arm_copy_reg_indices(vcpu, user_list->reg);
1424 break;
1425 }
1426 case KVM_SET_DEVICE_ATTR: {
1427 r = -EFAULT;
1428 if (copy_from_user(&attr, argp, sizeof(attr)))
1429 break;
1430 r = kvm_arm_vcpu_set_attr(vcpu, &attr);
1431 break;
1432 }
1433 case KVM_GET_DEVICE_ATTR: {
1434 r = -EFAULT;
1435 if (copy_from_user(&attr, argp, sizeof(attr)))
1436 break;
1437 r = kvm_arm_vcpu_get_attr(vcpu, &attr);
1438 break;
1439 }
1440 case KVM_HAS_DEVICE_ATTR: {
1441 r = -EFAULT;
1442 if (copy_from_user(&attr, argp, sizeof(attr)))
1443 break;
1444 r = kvm_arm_vcpu_has_attr(vcpu, &attr);
1445 break;
1446 }
1447 case KVM_GET_VCPU_EVENTS: {
1448 struct kvm_vcpu_events events;
1449
1450 if (kvm_arm_vcpu_get_events(vcpu, &events))
1451 return -EINVAL;
1452
1453 if (copy_to_user(argp, &events, sizeof(events)))
1454 return -EFAULT;
1455
1456 return 0;
1457 }
1458 case KVM_SET_VCPU_EVENTS: {
1459 struct kvm_vcpu_events events;
1460
1461 if (copy_from_user(&events, argp, sizeof(events)))
1462 return -EFAULT;
1463
1464 return kvm_arm_vcpu_set_events(vcpu, &events);
1465 }
1466 case KVM_ARM_VCPU_FINALIZE: {
1467 int what;
1468
1469 if (!kvm_vcpu_initialized(vcpu))
1470 return -ENOEXEC;
1471
1472 if (get_user(what, (const int __user *)argp))
1473 return -EFAULT;
1474
1475 return kvm_arm_vcpu_finalize(vcpu, what);
1476 }
1477 default:
1478 r = -EINVAL;
1479 }
1480
1481 return r;
1482 }
1483
kvm_arch_sync_dirty_log(struct kvm * kvm,struct kvm_memory_slot * memslot)1484 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
1485 {
1486
1487 }
1488
kvm_arch_flush_remote_tlbs_memslot(struct kvm * kvm,const struct kvm_memory_slot * memslot)1489 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
1490 const struct kvm_memory_slot *memslot)
1491 {
1492 kvm_flush_remote_tlbs(kvm);
1493 }
1494
kvm_vm_ioctl_set_device_addr(struct kvm * kvm,struct kvm_arm_device_addr * dev_addr)1495 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
1496 struct kvm_arm_device_addr *dev_addr)
1497 {
1498 unsigned long dev_id, type;
1499
1500 dev_id = (dev_addr->id & KVM_ARM_DEVICE_ID_MASK) >>
1501 KVM_ARM_DEVICE_ID_SHIFT;
1502 type = (dev_addr->id & KVM_ARM_DEVICE_TYPE_MASK) >>
1503 KVM_ARM_DEVICE_TYPE_SHIFT;
1504
1505 switch (dev_id) {
1506 case KVM_ARM_DEVICE_VGIC_V2:
1507 if (!vgic_present)
1508 return -ENXIO;
1509 return kvm_vgic_addr(kvm, type, &dev_addr->addr, true);
1510 default:
1511 return -ENODEV;
1512 }
1513 }
1514
kvm_arch_vm_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1515 long kvm_arch_vm_ioctl(struct file *filp,
1516 unsigned int ioctl, unsigned long arg)
1517 {
1518 struct kvm *kvm = filp->private_data;
1519 void __user *argp = (void __user *)arg;
1520
1521 switch (ioctl) {
1522 case KVM_CREATE_IRQCHIP: {
1523 int ret;
1524 if (!vgic_present)
1525 return -ENXIO;
1526 mutex_lock(&kvm->lock);
1527 ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2);
1528 mutex_unlock(&kvm->lock);
1529 return ret;
1530 }
1531 case KVM_ARM_SET_DEVICE_ADDR: {
1532 struct kvm_arm_device_addr dev_addr;
1533
1534 if (copy_from_user(&dev_addr, argp, sizeof(dev_addr)))
1535 return -EFAULT;
1536 return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr);
1537 }
1538 case KVM_ARM_PREFERRED_TARGET: {
1539 struct kvm_vcpu_init init;
1540
1541 kvm_vcpu_preferred_target(&init);
1542
1543 if (copy_to_user(argp, &init, sizeof(init)))
1544 return -EFAULT;
1545
1546 return 0;
1547 }
1548 case KVM_ARM_MTE_COPY_TAGS: {
1549 struct kvm_arm_copy_mte_tags copy_tags;
1550
1551 if (copy_from_user(©_tags, argp, sizeof(copy_tags)))
1552 return -EFAULT;
1553 return kvm_vm_ioctl_mte_copy_tags(kvm, ©_tags);
1554 }
1555 default:
1556 return -EINVAL;
1557 }
1558 }
1559
nvhe_percpu_size(void)1560 static unsigned long nvhe_percpu_size(void)
1561 {
1562 return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) -
1563 (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start);
1564 }
1565
nvhe_percpu_order(void)1566 static unsigned long nvhe_percpu_order(void)
1567 {
1568 unsigned long size = nvhe_percpu_size();
1569
1570 return size ? get_order(size) : 0;
1571 }
1572
1573 /* A lookup table holding the hypervisor VA for each vector slot */
1574 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS];
1575
kvm_init_vector_slot(void * base,enum arm64_hyp_spectre_vector slot)1576 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot)
1577 {
1578 hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot);
1579 }
1580
kvm_init_vector_slots(void)1581 static int kvm_init_vector_slots(void)
1582 {
1583 int err;
1584 void *base;
1585
1586 base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector));
1587 kvm_init_vector_slot(base, HYP_VECTOR_DIRECT);
1588
1589 base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs));
1590 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT);
1591
1592 if (kvm_system_needs_idmapped_vectors() &&
1593 !is_protected_kvm_enabled()) {
1594 err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs),
1595 __BP_HARDEN_HYP_VECS_SZ, &base);
1596 if (err)
1597 return err;
1598 }
1599
1600 kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT);
1601 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT);
1602 return 0;
1603 }
1604
cpu_prepare_hyp_mode(int cpu)1605 static void cpu_prepare_hyp_mode(int cpu)
1606 {
1607 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
1608 unsigned long tcr;
1609
1610 /*
1611 * Calculate the raw per-cpu offset without a translation from the
1612 * kernel's mapping to the linear mapping, and store it in tpidr_el2
1613 * so that we can use adr_l to access per-cpu variables in EL2.
1614 * Also drop the KASAN tag which gets in the way...
1615 */
1616 params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) -
1617 (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start));
1618
1619 params->mair_el2 = read_sysreg(mair_el1);
1620
1621 /*
1622 * The ID map may be configured to use an extended virtual address
1623 * range. This is only the case if system RAM is out of range for the
1624 * currently configured page size and VA_BITS, in which case we will
1625 * also need the extended virtual range for the HYP ID map, or we won't
1626 * be able to enable the EL2 MMU.
1627 *
1628 * However, at EL2, there is only one TTBR register, and we can't switch
1629 * between translation tables *and* update TCR_EL2.T0SZ at the same
1630 * time. Bottom line: we need to use the extended range with *both* our
1631 * translation tables.
1632 *
1633 * So use the same T0SZ value we use for the ID map.
1634 */
1635 tcr = (read_sysreg(tcr_el1) & TCR_EL2_MASK) | TCR_EL2_RES1;
1636 tcr &= ~TCR_T0SZ_MASK;
1637 tcr |= (idmap_t0sz & GENMASK(TCR_TxSZ_WIDTH - 1, 0)) << TCR_T0SZ_OFFSET;
1638 params->tcr_el2 = tcr;
1639
1640 params->stack_hyp_va = kern_hyp_va(per_cpu(kvm_arm_hyp_stack_page, cpu) + PAGE_SIZE);
1641 params->pgd_pa = kvm_mmu_get_httbr();
1642 if (is_protected_kvm_enabled())
1643 params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS;
1644 else
1645 params->hcr_el2 = HCR_HOST_NVHE_FLAGS;
1646 params->vttbr = params->vtcr = 0;
1647
1648 /*
1649 * Flush the init params from the data cache because the struct will
1650 * be read while the MMU is off.
1651 */
1652 kvm_flush_dcache_to_poc(params, sizeof(*params));
1653 }
1654
hyp_install_host_vector(void)1655 static void hyp_install_host_vector(void)
1656 {
1657 struct kvm_nvhe_init_params *params;
1658 struct arm_smccc_res res;
1659
1660 /* Switch from the HYP stub to our own HYP init vector */
1661 __hyp_set_vectors(kvm_get_idmap_vector());
1662
1663 /*
1664 * Call initialization code, and switch to the full blown HYP code.
1665 * If the cpucaps haven't been finalized yet, something has gone very
1666 * wrong, and hyp will crash and burn when it uses any
1667 * cpus_have_const_cap() wrapper.
1668 */
1669 BUG_ON(!system_capabilities_finalized());
1670 params = this_cpu_ptr_nvhe_sym(kvm_init_params);
1671 arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res);
1672 WARN_ON(res.a0 != SMCCC_RET_SUCCESS);
1673 }
1674
cpu_init_hyp_mode(void)1675 static void cpu_init_hyp_mode(void)
1676 {
1677 hyp_install_host_vector();
1678
1679 /*
1680 * Disabling SSBD on a non-VHE system requires us to enable SSBS
1681 * at EL2.
1682 */
1683 if (this_cpu_has_cap(ARM64_SSBS) &&
1684 arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) {
1685 kvm_call_hyp_nvhe(__kvm_enable_ssbs);
1686 }
1687 }
1688
cpu_hyp_reset(void)1689 static void cpu_hyp_reset(void)
1690 {
1691 if (!is_kernel_in_hyp_mode())
1692 __hyp_reset_vectors();
1693 }
1694
1695 /*
1696 * EL2 vectors can be mapped and rerouted in a number of ways,
1697 * depending on the kernel configuration and CPU present:
1698 *
1699 * - If the CPU is affected by Spectre-v2, the hardening sequence is
1700 * placed in one of the vector slots, which is executed before jumping
1701 * to the real vectors.
1702 *
1703 * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot
1704 * containing the hardening sequence is mapped next to the idmap page,
1705 * and executed before jumping to the real vectors.
1706 *
1707 * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an
1708 * empty slot is selected, mapped next to the idmap page, and
1709 * executed before jumping to the real vectors.
1710 *
1711 * Note that ARM64_SPECTRE_V3A is somewhat incompatible with
1712 * VHE, as we don't have hypervisor-specific mappings. If the system
1713 * is VHE and yet selects this capability, it will be ignored.
1714 */
cpu_set_hyp_vector(void)1715 static void cpu_set_hyp_vector(void)
1716 {
1717 struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data);
1718 void *vector = hyp_spectre_vector_selector[data->slot];
1719
1720 if (!is_protected_kvm_enabled())
1721 *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector;
1722 else
1723 kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot);
1724 }
1725
cpu_hyp_init_context(void)1726 static void cpu_hyp_init_context(void)
1727 {
1728 kvm_init_host_cpu_context(&this_cpu_ptr_hyp_sym(kvm_host_data)->host_ctxt);
1729
1730 if (!is_kernel_in_hyp_mode())
1731 cpu_init_hyp_mode();
1732 }
1733
cpu_hyp_init_features(void)1734 static void cpu_hyp_init_features(void)
1735 {
1736 cpu_set_hyp_vector();
1737 kvm_arm_init_debug();
1738
1739 if (is_kernel_in_hyp_mode())
1740 kvm_timer_init_vhe();
1741
1742 if (vgic_present)
1743 kvm_vgic_init_cpu_hardware();
1744 }
1745
cpu_hyp_reinit(void)1746 static void cpu_hyp_reinit(void)
1747 {
1748 cpu_hyp_reset();
1749 cpu_hyp_init_context();
1750 cpu_hyp_init_features();
1751 }
1752
_kvm_arch_hardware_enable(void * discard)1753 static void _kvm_arch_hardware_enable(void *discard)
1754 {
1755 if (!__this_cpu_read(kvm_arm_hardware_enabled)) {
1756 cpu_hyp_reinit();
1757 __this_cpu_write(kvm_arm_hardware_enabled, 1);
1758 }
1759 }
1760
kvm_arch_hardware_enable(void)1761 int kvm_arch_hardware_enable(void)
1762 {
1763 _kvm_arch_hardware_enable(NULL);
1764 return 0;
1765 }
1766
_kvm_arch_hardware_disable(void * discard)1767 static void _kvm_arch_hardware_disable(void *discard)
1768 {
1769 if (__this_cpu_read(kvm_arm_hardware_enabled)) {
1770 cpu_hyp_reset();
1771 __this_cpu_write(kvm_arm_hardware_enabled, 0);
1772 }
1773 }
1774
kvm_arch_hardware_disable(void)1775 void kvm_arch_hardware_disable(void)
1776 {
1777 if (!is_protected_kvm_enabled())
1778 _kvm_arch_hardware_disable(NULL);
1779 }
1780
1781 #ifdef CONFIG_CPU_PM
hyp_init_cpu_pm_notifier(struct notifier_block * self,unsigned long cmd,void * v)1782 static int hyp_init_cpu_pm_notifier(struct notifier_block *self,
1783 unsigned long cmd,
1784 void *v)
1785 {
1786 /*
1787 * kvm_arm_hardware_enabled is left with its old value over
1788 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should
1789 * re-enable hyp.
1790 */
1791 switch (cmd) {
1792 case CPU_PM_ENTER:
1793 if (__this_cpu_read(kvm_arm_hardware_enabled))
1794 /*
1795 * don't update kvm_arm_hardware_enabled here
1796 * so that the hardware will be re-enabled
1797 * when we resume. See below.
1798 */
1799 cpu_hyp_reset();
1800
1801 return NOTIFY_OK;
1802 case CPU_PM_ENTER_FAILED:
1803 case CPU_PM_EXIT:
1804 if (__this_cpu_read(kvm_arm_hardware_enabled))
1805 /* The hardware was enabled before suspend. */
1806 cpu_hyp_reinit();
1807
1808 return NOTIFY_OK;
1809
1810 default:
1811 return NOTIFY_DONE;
1812 }
1813 }
1814
1815 static struct notifier_block hyp_init_cpu_pm_nb = {
1816 .notifier_call = hyp_init_cpu_pm_notifier,
1817 };
1818
hyp_cpu_pm_init(void)1819 static void hyp_cpu_pm_init(void)
1820 {
1821 if (!is_protected_kvm_enabled())
1822 cpu_pm_register_notifier(&hyp_init_cpu_pm_nb);
1823 }
hyp_cpu_pm_exit(void)1824 static void hyp_cpu_pm_exit(void)
1825 {
1826 if (!is_protected_kvm_enabled())
1827 cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb);
1828 }
1829 #else
hyp_cpu_pm_init(void)1830 static inline void hyp_cpu_pm_init(void)
1831 {
1832 }
hyp_cpu_pm_exit(void)1833 static inline void hyp_cpu_pm_exit(void)
1834 {
1835 }
1836 #endif
1837
init_cpu_logical_map(void)1838 static void init_cpu_logical_map(void)
1839 {
1840 unsigned int cpu;
1841
1842 /*
1843 * Copy the MPIDR <-> logical CPU ID mapping to hyp.
1844 * Only copy the set of online CPUs whose features have been chacked
1845 * against the finalized system capabilities. The hypervisor will not
1846 * allow any other CPUs from the `possible` set to boot.
1847 */
1848 for_each_online_cpu(cpu)
1849 hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu);
1850 }
1851
1852 #define init_psci_0_1_impl_state(config, what) \
1853 config.psci_0_1_ ## what ## _implemented = psci_ops.what
1854
init_psci_relay(void)1855 static bool init_psci_relay(void)
1856 {
1857 /*
1858 * If PSCI has not been initialized, protected KVM cannot install
1859 * itself on newly booted CPUs.
1860 */
1861 if (!psci_ops.get_version) {
1862 kvm_err("Cannot initialize protected mode without PSCI\n");
1863 return false;
1864 }
1865
1866 kvm_host_psci_config.version = psci_ops.get_version();
1867 kvm_host_psci_config.smccc_version = arm_smccc_get_version();
1868
1869 if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) {
1870 kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids();
1871 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend);
1872 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on);
1873 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off);
1874 init_psci_0_1_impl_state(kvm_host_psci_config, migrate);
1875 }
1876 return true;
1877 }
1878
init_subsystems(void)1879 static int init_subsystems(void)
1880 {
1881 int err = 0;
1882
1883 /*
1884 * Enable hardware so that subsystem initialisation can access EL2.
1885 */
1886 on_each_cpu(_kvm_arch_hardware_enable, NULL, 1);
1887
1888 /*
1889 * Register CPU lower-power notifier
1890 */
1891 hyp_cpu_pm_init();
1892
1893 /*
1894 * Init HYP view of VGIC
1895 */
1896 err = kvm_vgic_hyp_init();
1897 switch (err) {
1898 case 0:
1899 vgic_present = true;
1900 break;
1901 case -ENODEV:
1902 case -ENXIO:
1903 vgic_present = false;
1904 err = 0;
1905 break;
1906 default:
1907 goto out;
1908 }
1909
1910 /*
1911 * Init HYP architected timer support
1912 */
1913 err = kvm_timer_hyp_init(vgic_present);
1914 if (err)
1915 goto out;
1916
1917 kvm_perf_init();
1918 kvm_sys_reg_table_init();
1919
1920 out:
1921 if (err || !is_protected_kvm_enabled())
1922 on_each_cpu(_kvm_arch_hardware_disable, NULL, 1);
1923
1924 return err;
1925 }
1926
teardown_hyp_mode(void)1927 static void teardown_hyp_mode(void)
1928 {
1929 int cpu;
1930
1931 free_hyp_pgds();
1932 for_each_possible_cpu(cpu) {
1933 free_page(per_cpu(kvm_arm_hyp_stack_page, cpu));
1934 free_pages(kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu], nvhe_percpu_order());
1935 }
1936 }
1937
do_pkvm_init(u32 hyp_va_bits)1938 static int do_pkvm_init(u32 hyp_va_bits)
1939 {
1940 void *per_cpu_base = kvm_ksym_ref(kvm_nvhe_sym(kvm_arm_hyp_percpu_base));
1941 int ret;
1942
1943 preempt_disable();
1944 cpu_hyp_init_context();
1945 ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size,
1946 num_possible_cpus(), kern_hyp_va(per_cpu_base),
1947 hyp_va_bits);
1948 cpu_hyp_init_features();
1949
1950 /*
1951 * The stub hypercalls are now disabled, so set our local flag to
1952 * prevent a later re-init attempt in kvm_arch_hardware_enable().
1953 */
1954 __this_cpu_write(kvm_arm_hardware_enabled, 1);
1955 preempt_enable();
1956
1957 return ret;
1958 }
1959
kvm_hyp_init_protection(u32 hyp_va_bits)1960 static int kvm_hyp_init_protection(u32 hyp_va_bits)
1961 {
1962 void *addr = phys_to_virt(hyp_mem_base);
1963 int ret;
1964
1965 kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
1966 kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1);
1967 kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1);
1968 kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1);
1969 kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
1970 kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
1971 kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1);
1972 kvm_nvhe_sym(__icache_flags) = __icache_flags;
1973 kvm_nvhe_sym(smccc_trng_available) = smccc_trng_available;
1974
1975 ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP);
1976 if (ret)
1977 return ret;
1978
1979 ret = do_pkvm_init(hyp_va_bits);
1980 if (ret)
1981 return ret;
1982
1983 free_hyp_pgds();
1984
1985 return 0;
1986 }
1987
1988 /**
1989 * Inits Hyp-mode on all online CPUs
1990 */
init_hyp_mode(void)1991 static int init_hyp_mode(void)
1992 {
1993 u32 hyp_va_bits;
1994 int cpu;
1995 int err = -ENOMEM;
1996
1997 /*
1998 * The protected Hyp-mode cannot be initialized if the memory pool
1999 * allocation has failed.
2000 */
2001 if (is_protected_kvm_enabled() && !hyp_mem_base)
2002 goto out_err;
2003
2004 /*
2005 * Allocate Hyp PGD and setup Hyp identity mapping
2006 */
2007 err = kvm_mmu_init(&hyp_va_bits);
2008 if (err)
2009 goto out_err;
2010
2011 /*
2012 * Allocate stack pages for Hypervisor-mode
2013 */
2014 for_each_possible_cpu(cpu) {
2015 unsigned long stack_page;
2016
2017 stack_page = __get_free_page(GFP_KERNEL);
2018 if (!stack_page) {
2019 err = -ENOMEM;
2020 goto out_err;
2021 }
2022
2023 per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page;
2024 }
2025
2026 /*
2027 * Allocate and initialize pages for Hypervisor-mode percpu regions.
2028 */
2029 for_each_possible_cpu(cpu) {
2030 struct page *page;
2031 void *page_addr;
2032
2033 page = alloc_pages(GFP_KERNEL, nvhe_percpu_order());
2034 if (!page) {
2035 err = -ENOMEM;
2036 goto out_err;
2037 }
2038
2039 page_addr = page_address(page);
2040 memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size());
2041 kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu] = (unsigned long)page_addr;
2042 }
2043
2044 /*
2045 * Map the Hyp-code called directly from the host
2046 */
2047 err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start),
2048 kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC);
2049 if (err) {
2050 kvm_err("Cannot map world-switch code\n");
2051 goto out_err;
2052 }
2053
2054 err = create_hyp_mappings(kvm_ksym_ref(__hyp_data_start),
2055 kvm_ksym_ref(__hyp_data_end), PAGE_HYP);
2056 if (err) {
2057 kvm_err("Cannot map .hyp.data section\n");
2058 goto out_err;
2059 }
2060
2061 err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start),
2062 kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO);
2063 if (err) {
2064 kvm_err("Cannot map .hyp.rodata section\n");
2065 goto out_err;
2066 }
2067
2068 err = create_hyp_mappings(kvm_ksym_ref(__start_rodata),
2069 kvm_ksym_ref(__end_rodata), PAGE_HYP_RO);
2070 if (err) {
2071 kvm_err("Cannot map rodata section\n");
2072 goto out_err;
2073 }
2074
2075 /*
2076 * .hyp.bss is guaranteed to be placed at the beginning of the .bss
2077 * section thanks to an assertion in the linker script. Map it RW and
2078 * the rest of .bss RO.
2079 */
2080 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start),
2081 kvm_ksym_ref(__hyp_bss_end), PAGE_HYP);
2082 if (err) {
2083 kvm_err("Cannot map hyp bss section: %d\n", err);
2084 goto out_err;
2085 }
2086
2087 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end),
2088 kvm_ksym_ref(__bss_stop), PAGE_HYP_RO);
2089 if (err) {
2090 kvm_err("Cannot map bss section\n");
2091 goto out_err;
2092 }
2093
2094 /*
2095 * Map the Hyp stack pages
2096 */
2097 for_each_possible_cpu(cpu) {
2098 char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu);
2099 err = create_hyp_mappings(stack_page, stack_page + PAGE_SIZE,
2100 PAGE_HYP);
2101
2102 if (err) {
2103 kvm_err("Cannot map hyp stack\n");
2104 goto out_err;
2105 }
2106 }
2107
2108 for_each_possible_cpu(cpu) {
2109 char *percpu_begin = (char *)kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu];
2110 char *percpu_end = percpu_begin + nvhe_percpu_size();
2111
2112 /* Map Hyp percpu pages */
2113 err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP);
2114 if (err) {
2115 kvm_err("Cannot map hyp percpu region\n");
2116 goto out_err;
2117 }
2118
2119 /* Prepare the CPU initialization parameters */
2120 cpu_prepare_hyp_mode(cpu);
2121 }
2122
2123 if (is_protected_kvm_enabled()) {
2124 init_cpu_logical_map();
2125
2126 if (!init_psci_relay()) {
2127 err = -ENODEV;
2128 goto out_err;
2129 }
2130 }
2131
2132 if (is_protected_kvm_enabled()) {
2133 err = kvm_hyp_init_protection(hyp_va_bits);
2134 if (err) {
2135 kvm_err("Failed to init hyp memory protection\n");
2136 goto out_err;
2137 }
2138 }
2139
2140 return 0;
2141
2142 out_err:
2143 teardown_hyp_mode();
2144 kvm_err("error initializing Hyp mode: %d\n", err);
2145 return err;
2146 }
2147
_kvm_host_prot_finalize(void * arg)2148 static void _kvm_host_prot_finalize(void *arg)
2149 {
2150 int *err = arg;
2151
2152 if (WARN_ON(kvm_call_hyp_nvhe(__pkvm_prot_finalize)))
2153 WRITE_ONCE(*err, -EINVAL);
2154 }
2155
pkvm_drop_host_privileges(void)2156 static int pkvm_drop_host_privileges(void)
2157 {
2158 int ret = 0;
2159
2160 /*
2161 * Flip the static key upfront as that may no longer be possible
2162 * once the host stage 2 is installed.
2163 */
2164 static_branch_enable(&kvm_protected_mode_initialized);
2165
2166 /*
2167 * Fixup the boot mode so that we don't take spurious round
2168 * trips via EL2 on cpu_resume. Flush to the PoC for a good
2169 * measure, so that it can be observed by a CPU coming out of
2170 * suspend with the MMU off.
2171 */
2172 __boot_cpu_mode[0] = __boot_cpu_mode[1] = BOOT_CPU_MODE_EL1;
2173 dcache_clean_poc((unsigned long)__boot_cpu_mode,
2174 (unsigned long)(__boot_cpu_mode + 2));
2175
2176 on_each_cpu(_kvm_host_prot_finalize, &ret, 1);
2177 return ret;
2178 }
2179
finalize_hyp_mode(void)2180 static int finalize_hyp_mode(void)
2181 {
2182 if (!is_protected_kvm_enabled())
2183 return 0;
2184
2185 /*
2186 * Exclude HYP sections from kmemleak so that they don't get peeked
2187 * at, which would end badly once inaccessible.
2188 */
2189 kmemleak_free_part(__hyp_bss_start, __hyp_bss_end - __hyp_bss_start);
2190 kmemleak_free_part(__hyp_data_start, __hyp_data_end - __hyp_data_start);
2191 kmemleak_free_part(__va(hyp_mem_base), hyp_mem_size);
2192 return pkvm_drop_host_privileges();
2193 }
2194
kvm_mpidr_to_vcpu(struct kvm * kvm,unsigned long mpidr)2195 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr)
2196 {
2197 struct kvm_vcpu *vcpu;
2198 int i;
2199
2200 mpidr &= MPIDR_HWID_BITMASK;
2201 kvm_for_each_vcpu(i, vcpu, kvm) {
2202 if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu))
2203 return vcpu;
2204 }
2205 return NULL;
2206 }
2207
kvm_arch_has_irq_bypass(void)2208 bool kvm_arch_has_irq_bypass(void)
2209 {
2210 return true;
2211 }
2212
kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)2213 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
2214 struct irq_bypass_producer *prod)
2215 {
2216 struct kvm_kernel_irqfd *irqfd =
2217 container_of(cons, struct kvm_kernel_irqfd, consumer);
2218
2219 return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq,
2220 &irqfd->irq_entry);
2221 }
kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)2222 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
2223 struct irq_bypass_producer *prod)
2224 {
2225 struct kvm_kernel_irqfd *irqfd =
2226 container_of(cons, struct kvm_kernel_irqfd, consumer);
2227
2228 kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq,
2229 &irqfd->irq_entry);
2230 }
2231
kvm_arch_irq_bypass_stop(struct irq_bypass_consumer * cons)2232 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons)
2233 {
2234 struct kvm_kernel_irqfd *irqfd =
2235 container_of(cons, struct kvm_kernel_irqfd, consumer);
2236
2237 kvm_arm_halt_guest(irqfd->kvm);
2238 }
2239
kvm_arch_irq_bypass_start(struct irq_bypass_consumer * cons)2240 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons)
2241 {
2242 struct kvm_kernel_irqfd *irqfd =
2243 container_of(cons, struct kvm_kernel_irqfd, consumer);
2244
2245 kvm_arm_resume_guest(irqfd->kvm);
2246 }
2247
2248 /**
2249 * Initialize Hyp-mode and memory mappings on all CPUs.
2250 */
kvm_arch_init(void * opaque)2251 int kvm_arch_init(void *opaque)
2252 {
2253 int err;
2254 bool in_hyp_mode;
2255
2256 if (!is_hyp_mode_available()) {
2257 kvm_info("HYP mode not available\n");
2258 return -ENODEV;
2259 }
2260
2261 if (kvm_get_mode() == KVM_MODE_NONE) {
2262 kvm_info("KVM disabled from command line\n");
2263 return -ENODEV;
2264 }
2265
2266 in_hyp_mode = is_kernel_in_hyp_mode();
2267
2268 if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) ||
2269 cpus_have_final_cap(ARM64_WORKAROUND_1508412))
2270 kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \
2271 "Only trusted guests should be used on this system.\n");
2272
2273 err = kvm_set_ipa_limit();
2274 if (err)
2275 return err;
2276
2277 err = kvm_arm_init_sve();
2278 if (err)
2279 return err;
2280
2281 if (!in_hyp_mode) {
2282 err = init_hyp_mode();
2283 if (err)
2284 goto out_err;
2285 }
2286
2287 err = kvm_init_vector_slots();
2288 if (err) {
2289 kvm_err("Cannot initialise vector slots\n");
2290 goto out_err;
2291 }
2292
2293 err = init_subsystems();
2294 if (err)
2295 goto out_hyp;
2296
2297 if (!in_hyp_mode) {
2298 err = finalize_hyp_mode();
2299 if (err) {
2300 kvm_err("Failed to finalize Hyp protection\n");
2301 goto out_hyp;
2302 }
2303 }
2304
2305 if (is_protected_kvm_enabled()) {
2306 kvm_info("Protected nVHE mode initialized successfully\n");
2307 } else if (in_hyp_mode) {
2308 kvm_info("VHE mode initialized successfully\n");
2309 } else {
2310 kvm_info("Hyp mode initialized successfully\n");
2311 }
2312
2313 return 0;
2314
2315 out_hyp:
2316 hyp_cpu_pm_exit();
2317 if (!in_hyp_mode)
2318 teardown_hyp_mode();
2319 out_err:
2320 return err;
2321 }
2322
2323 /* NOP: Compiling as a module not supported */
kvm_arch_exit(void)2324 void kvm_arch_exit(void)
2325 {
2326 kvm_perf_teardown();
2327 }
2328
early_kvm_mode_cfg(char * arg)2329 static int __init early_kvm_mode_cfg(char *arg)
2330 {
2331 if (!arg)
2332 return -EINVAL;
2333
2334 if (strcmp(arg, "none") == 0) {
2335 kvm_mode = KVM_MODE_NONE;
2336 return 0;
2337 }
2338
2339 if (!is_hyp_mode_available()) {
2340 pr_warn_once("KVM is not available. Ignoring kvm-arm.mode\n");
2341 return 0;
2342 }
2343
2344 if (strcmp(arg, "protected") == 0) {
2345 if (!is_kernel_in_hyp_mode())
2346 kvm_mode = KVM_MODE_PROTECTED;
2347 else
2348 pr_warn_once("Protected KVM not available with VHE\n");
2349
2350 return 0;
2351 }
2352
2353 if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) {
2354 kvm_mode = KVM_MODE_DEFAULT;
2355 return 0;
2356 }
2357
2358 return -EINVAL;
2359 }
2360 early_param("kvm-arm.mode", early_kvm_mode_cfg);
2361
kvm_get_mode(void)2362 enum kvm_mode kvm_get_mode(void)
2363 {
2364 return kvm_mode;
2365 }
2366
arm_init(void)2367 static int arm_init(void)
2368 {
2369 int rc = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
2370 return rc;
2371 }
2372
2373 module_init(arm_init);
2374