xref: /linux/arch/arm64/kvm/hyp/vhe/switch.c (revision e0c0ab04f6785abaa71b9b8dc252cb1a2072c225)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2015 - ARM Ltd
4  * Author: Marc Zyngier <marc.zyngier@arm.com>
5  */
6 
7 #include <hyp/switch.h>
8 
9 #include <linux/arm-smccc.h>
10 #include <linux/kvm_host.h>
11 #include <linux/types.h>
12 #include <linux/jump_label.h>
13 #include <linux/percpu.h>
14 #include <uapi/linux/psci.h>
15 
16 #include <kvm/arm_psci.h>
17 
18 #include <asm/barrier.h>
19 #include <asm/cpufeature.h>
20 #include <asm/kprobes.h>
21 #include <asm/kvm_asm.h>
22 #include <asm/kvm_emulate.h>
23 #include <asm/kvm_hyp.h>
24 #include <asm/kvm_mmu.h>
25 #include <asm/fpsimd.h>
26 #include <asm/debug-monitors.h>
27 #include <asm/processor.h>
28 #include <asm/thread_info.h>
29 #include <asm/vectors.h>
30 
31 /* VHE specific context */
32 DEFINE_PER_CPU(struct kvm_host_data, kvm_host_data);
33 DEFINE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt);
34 DEFINE_PER_CPU(unsigned long, kvm_hyp_vector);
35 
36 /*
37  * HCR_EL2 bits that the NV guest can freely change (no RES0/RES1
38  * semantics, irrespective of the configuration), but that cannot be
39  * applied to the actual HW as things would otherwise break badly.
40  *
41  * - TGE: we want the guest to use EL1, which is incompatible with
42  *   this bit being set
43  *
44  * - API/APK: they are already accounted for by vcpu_load(), and can
45  *   only take effect across a load/put cycle (such as ERET)
46  */
47 #define NV_HCR_GUEST_EXCLUDE	(HCR_TGE | HCR_API | HCR_APK)
48 
49 static u64 __compute_hcr(struct kvm_vcpu *vcpu)
50 {
51 	u64 guest_hcr = __vcpu_sys_reg(vcpu, HCR_EL2);
52 	u64 hcr = vcpu->arch.hcr_el2;
53 
54 	if (!vcpu_has_nv(vcpu))
55 		return hcr;
56 
57 	/*
58 	 * We rely on the invariant that a vcpu entered from HYP
59 	 * context must also exit in the same context, as only an ERET
60 	 * instruction can kick us out of it, and we obviously trap
61 	 * that sucker. PSTATE.M will get fixed-up on exit.
62 	 */
63 	if (is_hyp_ctxt(vcpu)) {
64 		host_data_set_flag(VCPU_IN_HYP_CONTEXT);
65 
66 		hcr |= HCR_NV | HCR_NV2 | HCR_AT | HCR_TTLB;
67 
68 		if (!vcpu_el2_e2h_is_set(vcpu))
69 			hcr |= HCR_NV1;
70 
71 		write_sysreg_s(vcpu->arch.ctxt.vncr_array, SYS_VNCR_EL2);
72 	} else {
73 		host_data_clear_flag(VCPU_IN_HYP_CONTEXT);
74 
75 		if (guest_hcr & HCR_NV) {
76 			u64 va = __fix_to_virt(vncr_fixmap(smp_processor_id()));
77 
78 			/* Inherit the low bits from the actual register */
79 			va |= __vcpu_sys_reg(vcpu, VNCR_EL2) & GENMASK(PAGE_SHIFT - 1, 0);
80 			write_sysreg_s(va, SYS_VNCR_EL2);
81 
82 			/* Force NV2 in case the guest is forgetful... */
83 			guest_hcr |= HCR_NV2;
84 		}
85 	}
86 
87 	BUG_ON(host_data_test_flag(VCPU_IN_HYP_CONTEXT) &&
88 	       host_data_test_flag(L1_VNCR_MAPPED));
89 
90 	return hcr | (guest_hcr & ~NV_HCR_GUEST_EXCLUDE);
91 }
92 
93 static void __activate_cptr_traps(struct kvm_vcpu *vcpu)
94 {
95 	u64 cptr;
96 
97 	/*
98 	 * With VHE (HCR.E2H == 1), accesses to CPACR_EL1 are routed to
99 	 * CPTR_EL2. In general, CPACR_EL1 has the same layout as CPTR_EL2,
100 	 * except for some missing controls, such as TAM.
101 	 * In this case, CPTR_EL2.TAM has the same position with or without
102 	 * VHE (HCR.E2H == 1) which allows us to use here the CPTR_EL2.TAM
103 	 * shift value for trapping the AMU accesses.
104 	 */
105 	u64 val = CPACR_EL1_TTA | CPTR_EL2_TAM;
106 
107 	if (guest_owns_fp_regs()) {
108 		val |= CPACR_EL1_FPEN;
109 		if (vcpu_has_sve(vcpu))
110 			val |= CPACR_EL1_ZEN;
111 	} else {
112 		__activate_traps_fpsimd32(vcpu);
113 	}
114 
115 	if (!vcpu_has_nv(vcpu))
116 		goto write;
117 
118 	/*
119 	 * The architecture is a bit crap (what a surprise): an EL2 guest
120 	 * writing to CPTR_EL2 via CPACR_EL1 can't set any of TCPAC or TTA,
121 	 * as they are RES0 in the guest's view. To work around it, trap the
122 	 * sucker using the very same bit it can't set...
123 	 */
124 	if (vcpu_el2_e2h_is_set(vcpu) && is_hyp_ctxt(vcpu))
125 		val |= CPTR_EL2_TCPAC;
126 
127 	/*
128 	 * Layer the guest hypervisor's trap configuration on top of our own if
129 	 * we're in a nested context.
130 	 */
131 	if (is_hyp_ctxt(vcpu))
132 		goto write;
133 
134 	cptr = vcpu_sanitised_cptr_el2(vcpu);
135 
136 	/*
137 	 * Pay attention, there's some interesting detail here.
138 	 *
139 	 * The CPTR_EL2.xEN fields are 2 bits wide, although there are only two
140 	 * meaningful trap states when HCR_EL2.TGE = 0 (running a nested guest):
141 	 *
142 	 *  - CPTR_EL2.xEN = x0, traps are enabled
143 	 *  - CPTR_EL2.xEN = x1, traps are disabled
144 	 *
145 	 * In other words, bit[0] determines if guest accesses trap or not. In
146 	 * the interest of simplicity, clear the entire field if the guest
147 	 * hypervisor has traps enabled to dispel any illusion of something more
148 	 * complicated taking place.
149 	 */
150 	if (!(SYS_FIELD_GET(CPACR_EL1, FPEN, cptr) & BIT(0)))
151 		val &= ~CPACR_EL1_FPEN;
152 	if (!(SYS_FIELD_GET(CPACR_EL1, ZEN, cptr) & BIT(0)))
153 		val &= ~CPACR_EL1_ZEN;
154 
155 	if (kvm_has_feat(vcpu->kvm, ID_AA64MMFR3_EL1, S2POE, IMP))
156 		val |= cptr & CPACR_EL1_E0POE;
157 
158 	val |= cptr & CPTR_EL2_TCPAC;
159 
160 write:
161 	write_sysreg(val, cpacr_el1);
162 }
163 
164 static void __deactivate_cptr_traps(struct kvm_vcpu *vcpu)
165 {
166 	u64 val = CPACR_EL1_FPEN | CPACR_EL1_ZEN_EL1EN;
167 
168 	if (cpus_have_final_cap(ARM64_SME))
169 		val |= CPACR_EL1_SMEN_EL1EN;
170 
171 	write_sysreg(val, cpacr_el1);
172 }
173 
174 static void __activate_traps(struct kvm_vcpu *vcpu)
175 {
176 	u64 val;
177 
178 	___activate_traps(vcpu, __compute_hcr(vcpu));
179 
180 	if (has_cntpoff()) {
181 		struct timer_map map;
182 
183 		get_timer_map(vcpu, &map);
184 
185 		/*
186 		 * We're entrering the guest. Reload the correct
187 		 * values from memory now that TGE is clear.
188 		 */
189 		if (map.direct_ptimer == vcpu_ptimer(vcpu))
190 			val = __vcpu_sys_reg(vcpu, CNTP_CVAL_EL0);
191 		if (map.direct_ptimer == vcpu_hptimer(vcpu))
192 			val = __vcpu_sys_reg(vcpu, CNTHP_CVAL_EL2);
193 
194 		if (map.direct_ptimer) {
195 			write_sysreg_el0(val, SYS_CNTP_CVAL);
196 			isb();
197 		}
198 	}
199 
200 	__activate_cptr_traps(vcpu);
201 
202 	write_sysreg(__this_cpu_read(kvm_hyp_vector), vbar_el1);
203 }
204 NOKPROBE_SYMBOL(__activate_traps);
205 
206 static void __deactivate_traps(struct kvm_vcpu *vcpu)
207 {
208 	const char *host_vectors = vectors;
209 
210 	___deactivate_traps(vcpu);
211 
212 	write_sysreg_hcr(HCR_HOST_VHE_FLAGS);
213 
214 	if (has_cntpoff()) {
215 		struct timer_map map;
216 		u64 val, offset;
217 
218 		get_timer_map(vcpu, &map);
219 
220 		/*
221 		 * We're exiting the guest. Save the latest CVAL value
222 		 * to memory and apply the offset now that TGE is set.
223 		 */
224 		val = read_sysreg_el0(SYS_CNTP_CVAL);
225 		if (map.direct_ptimer == vcpu_ptimer(vcpu))
226 			__vcpu_assign_sys_reg(vcpu, CNTP_CVAL_EL0, val);
227 		if (map.direct_ptimer == vcpu_hptimer(vcpu))
228 			__vcpu_assign_sys_reg(vcpu, CNTHP_CVAL_EL2, val);
229 
230 		offset = read_sysreg_s(SYS_CNTPOFF_EL2);
231 
232 		if (map.direct_ptimer && offset) {
233 			write_sysreg_el0(val + offset, SYS_CNTP_CVAL);
234 			isb();
235 		}
236 	}
237 
238 	/*
239 	 * ARM errata 1165522 and 1530923 require the actual execution of the
240 	 * above before we can switch to the EL2/EL0 translation regime used by
241 	 * the host.
242 	 */
243 	asm(ALTERNATIVE("nop", "isb", ARM64_WORKAROUND_SPECULATIVE_AT));
244 
245 	__deactivate_cptr_traps(vcpu);
246 
247 	if (!arm64_kernel_unmapped_at_el0())
248 		host_vectors = __this_cpu_read(this_cpu_vector);
249 	write_sysreg(host_vectors, vbar_el1);
250 }
251 NOKPROBE_SYMBOL(__deactivate_traps);
252 
253 /*
254  * Disable IRQs in __vcpu_{load,put}_{activate,deactivate}_traps() to
255  * prevent a race condition between context switching of PMUSERENR_EL0
256  * in __{activate,deactivate}_traps_common() and IPIs that attempts to
257  * update PMUSERENR_EL0. See also kvm_set_pmuserenr().
258  */
259 static void __vcpu_load_activate_traps(struct kvm_vcpu *vcpu)
260 {
261 	unsigned long flags;
262 
263 	local_irq_save(flags);
264 	__activate_traps_common(vcpu);
265 	local_irq_restore(flags);
266 }
267 
268 static void __vcpu_put_deactivate_traps(struct kvm_vcpu *vcpu)
269 {
270 	unsigned long flags;
271 
272 	local_irq_save(flags);
273 	__deactivate_traps_common(vcpu);
274 	local_irq_restore(flags);
275 }
276 
277 void kvm_vcpu_load_vhe(struct kvm_vcpu *vcpu)
278 {
279 	host_data_ptr(host_ctxt)->__hyp_running_vcpu = vcpu;
280 
281 	__vcpu_load_switch_sysregs(vcpu);
282 	__vcpu_load_activate_traps(vcpu);
283 	__load_stage2(vcpu->arch.hw_mmu, vcpu->arch.hw_mmu->arch);
284 }
285 
286 void kvm_vcpu_put_vhe(struct kvm_vcpu *vcpu)
287 {
288 	__vcpu_put_deactivate_traps(vcpu);
289 	__vcpu_put_switch_sysregs(vcpu);
290 
291 	host_data_ptr(host_ctxt)->__hyp_running_vcpu = NULL;
292 }
293 
294 static u64 compute_emulated_cntx_ctl_el0(struct kvm_vcpu *vcpu,
295 					 enum vcpu_sysreg reg)
296 {
297 	unsigned long ctl;
298 	u64 cval, cnt;
299 	bool stat;
300 
301 	switch (reg) {
302 	case CNTP_CTL_EL0:
303 		cval = __vcpu_sys_reg(vcpu, CNTP_CVAL_EL0);
304 		ctl  = __vcpu_sys_reg(vcpu, CNTP_CTL_EL0);
305 		cnt  = compute_counter_value(vcpu_ptimer(vcpu));
306 		break;
307 	case CNTV_CTL_EL0:
308 		cval = __vcpu_sys_reg(vcpu, CNTV_CVAL_EL0);
309 		ctl  = __vcpu_sys_reg(vcpu, CNTV_CTL_EL0);
310 		cnt  = compute_counter_value(vcpu_vtimer(vcpu));
311 		break;
312 	default:
313 		BUG();
314 	}
315 
316 	stat = cval <= cnt;
317 	__assign_bit(__ffs(ARCH_TIMER_CTRL_IT_STAT), &ctl, stat);
318 
319 	return ctl;
320 }
321 
322 static bool kvm_hyp_handle_timer(struct kvm_vcpu *vcpu, u64 *exit_code)
323 {
324 	u64 esr, val;
325 
326 	/*
327 	 * Having FEAT_ECV allows for a better quality of timer emulation.
328 	 * However, this comes at a huge cost in terms of traps. Try and
329 	 * satisfy the reads from guest's hypervisor context without
330 	 * returning to the kernel if we can.
331 	 */
332 	if (!is_hyp_ctxt(vcpu))
333 		return false;
334 
335 	esr = kvm_vcpu_get_esr(vcpu);
336 	if ((esr & ESR_ELx_SYS64_ISS_DIR_MASK) != ESR_ELx_SYS64_ISS_DIR_READ)
337 		return false;
338 
339 	switch (esr_sys64_to_sysreg(esr)) {
340 	case SYS_CNTP_CTL_EL02:
341 		val = compute_emulated_cntx_ctl_el0(vcpu, CNTP_CTL_EL0);
342 		break;
343 	case SYS_CNTP_CTL_EL0:
344 		if (vcpu_el2_e2h_is_set(vcpu))
345 			val = read_sysreg_el0(SYS_CNTP_CTL);
346 		else
347 			val = compute_emulated_cntx_ctl_el0(vcpu, CNTP_CTL_EL0);
348 		break;
349 	case SYS_CNTP_CVAL_EL02:
350 		val = __vcpu_sys_reg(vcpu, CNTP_CVAL_EL0);
351 		break;
352 	case SYS_CNTP_CVAL_EL0:
353 		if (vcpu_el2_e2h_is_set(vcpu)) {
354 			val = read_sysreg_el0(SYS_CNTP_CVAL);
355 
356 			if (!has_cntpoff())
357 				val -= timer_get_offset(vcpu_hptimer(vcpu));
358 		} else {
359 			val = __vcpu_sys_reg(vcpu, CNTP_CVAL_EL0);
360 		}
361 		break;
362 	case SYS_CNTPCT_EL0:
363 	case SYS_CNTPCTSS_EL0:
364 		val = compute_counter_value(vcpu_hptimer(vcpu));
365 		break;
366 	case SYS_CNTV_CTL_EL02:
367 		val = compute_emulated_cntx_ctl_el0(vcpu, CNTV_CTL_EL0);
368 		break;
369 	case SYS_CNTV_CTL_EL0:
370 		if (vcpu_el2_e2h_is_set(vcpu))
371 			val = read_sysreg_el0(SYS_CNTV_CTL);
372 		else
373 			val = compute_emulated_cntx_ctl_el0(vcpu, CNTV_CTL_EL0);
374 		break;
375 	case SYS_CNTV_CVAL_EL02:
376 		val = __vcpu_sys_reg(vcpu, CNTV_CVAL_EL0);
377 		break;
378 	case SYS_CNTV_CVAL_EL0:
379 		if (vcpu_el2_e2h_is_set(vcpu))
380 			val = read_sysreg_el0(SYS_CNTV_CVAL);
381 		else
382 			val = __vcpu_sys_reg(vcpu, CNTV_CVAL_EL0);
383 		break;
384 	case SYS_CNTVCT_EL0:
385 	case SYS_CNTVCTSS_EL0:
386 		val = compute_counter_value(vcpu_hvtimer(vcpu));
387 		break;
388 	default:
389 		return false;
390 	}
391 
392 	vcpu_set_reg(vcpu, kvm_vcpu_sys_get_rt(vcpu), val);
393 	__kvm_skip_instr(vcpu);
394 
395 	return true;
396 }
397 
398 static bool kvm_hyp_handle_eret(struct kvm_vcpu *vcpu, u64 *exit_code)
399 {
400 	u64 esr = kvm_vcpu_get_esr(vcpu);
401 	u64 spsr, elr, mode;
402 
403 	/*
404 	 * Going through the whole put/load motions is a waste of time
405 	 * if this is a VHE guest hypervisor returning to its own
406 	 * userspace, or the hypervisor performing a local exception
407 	 * return. No need to save/restore registers, no need to
408 	 * switch S2 MMU. Just do the canonical ERET.
409 	 *
410 	 * Unless the trap has to be forwarded further down the line,
411 	 * of course...
412 	 */
413 	if ((__vcpu_sys_reg(vcpu, HCR_EL2) & HCR_NV) ||
414 	    (__vcpu_sys_reg(vcpu, HFGITR_EL2) & HFGITR_EL2_ERET))
415 		return false;
416 
417 	spsr = read_sysreg_el1(SYS_SPSR);
418 	mode = spsr & (PSR_MODE_MASK | PSR_MODE32_BIT);
419 
420 	switch (mode) {
421 	case PSR_MODE_EL0t:
422 		if (!(vcpu_el2_e2h_is_set(vcpu) && vcpu_el2_tge_is_set(vcpu)))
423 			return false;
424 		break;
425 	case PSR_MODE_EL2t:
426 		mode = PSR_MODE_EL1t;
427 		break;
428 	case PSR_MODE_EL2h:
429 		mode = PSR_MODE_EL1h;
430 		break;
431 	default:
432 		return false;
433 	}
434 
435 	/* If ERETAx fails, take the slow path */
436 	if (esr_iss_is_eretax(esr)) {
437 		if (!(vcpu_has_ptrauth(vcpu) && kvm_auth_eretax(vcpu, &elr)))
438 			return false;
439 	} else {
440 		elr = read_sysreg_el1(SYS_ELR);
441 	}
442 
443 	spsr = (spsr & ~(PSR_MODE_MASK | PSR_MODE32_BIT)) | mode;
444 
445 	write_sysreg_el2(spsr, SYS_SPSR);
446 	write_sysreg_el2(elr, SYS_ELR);
447 
448 	return true;
449 }
450 
451 static bool kvm_hyp_handle_tlbi_el2(struct kvm_vcpu *vcpu, u64 *exit_code)
452 {
453 	int ret = -EINVAL;
454 	u32 instr;
455 	u64 val;
456 
457 	/*
458 	 * Ideally, we would never trap on EL2 S1 TLB invalidations using
459 	 * the EL1 instructions when the guest's HCR_EL2.{E2H,TGE}=={1,1}.
460 	 * But "thanks" to FEAT_NV2, we don't trap writes to HCR_EL2,
461 	 * meaning that we can't track changes to the virtual TGE bit. So we
462 	 * have to leave HCR_EL2.TTLB set on the host. Oopsie...
463 	 *
464 	 * Try and handle these invalidation as quickly as possible, without
465 	 * fully exiting. Note that we don't need to consider any forwarding
466 	 * here, as having E2H+TGE set is the very definition of being
467 	 * InHost.
468 	 *
469 	 * For the lesser hypervisors out there that have failed to get on
470 	 * with the VHE program, we can also handle the nVHE style of EL2
471 	 * invalidation.
472 	 */
473 	if (!(is_hyp_ctxt(vcpu)))
474 		return false;
475 
476 	instr = esr_sys64_to_sysreg(kvm_vcpu_get_esr(vcpu));
477 	val = vcpu_get_reg(vcpu, kvm_vcpu_sys_get_rt(vcpu));
478 
479 	if ((kvm_supported_tlbi_s1e1_op(vcpu, instr) &&
480 	     vcpu_el2_e2h_is_set(vcpu) && vcpu_el2_tge_is_set(vcpu)) ||
481 	    kvm_supported_tlbi_s1e2_op (vcpu, instr))
482 		ret = __kvm_tlbi_s1e2(NULL, val, instr);
483 
484 	if (ret)
485 		return false;
486 
487 	/*
488 	 * If we have to check for any VNCR mapping being invalidated,
489 	 * go back to the slow path for further processing.
490 	 */
491 	if (vcpu_el2_e2h_is_set(vcpu) && vcpu_el2_tge_is_set(vcpu) &&
492 	    atomic_read(&vcpu->kvm->arch.vncr_map_count))
493 		return false;
494 
495 	__kvm_skip_instr(vcpu);
496 
497 	return true;
498 }
499 
500 static bool kvm_hyp_handle_cpacr_el1(struct kvm_vcpu *vcpu, u64 *exit_code)
501 {
502 	u64 esr = kvm_vcpu_get_esr(vcpu);
503 	int rt;
504 
505 	if (!is_hyp_ctxt(vcpu) || esr_sys64_to_sysreg(esr) != SYS_CPACR_EL1)
506 		return false;
507 
508 	rt = kvm_vcpu_sys_get_rt(vcpu);
509 
510 	if ((esr & ESR_ELx_SYS64_ISS_DIR_MASK) == ESR_ELx_SYS64_ISS_DIR_READ) {
511 		vcpu_set_reg(vcpu, rt, __vcpu_sys_reg(vcpu, CPTR_EL2));
512 	} else {
513 		vcpu_write_sys_reg(vcpu, vcpu_get_reg(vcpu, rt), CPTR_EL2);
514 		__activate_cptr_traps(vcpu);
515 	}
516 
517 	__kvm_skip_instr(vcpu);
518 
519 	return true;
520 }
521 
522 static bool kvm_hyp_handle_zcr_el2(struct kvm_vcpu *vcpu, u64 *exit_code)
523 {
524 	u32 sysreg = esr_sys64_to_sysreg(kvm_vcpu_get_esr(vcpu));
525 
526 	if (!vcpu_has_nv(vcpu))
527 		return false;
528 
529 	if (sysreg != SYS_ZCR_EL2)
530 		return false;
531 
532 	if (guest_owns_fp_regs())
533 		return false;
534 
535 	/*
536 	 * ZCR_EL2 traps are handled in the slow path, with the expectation
537 	 * that the guest's FP context has already been loaded onto the CPU.
538 	 *
539 	 * Load the guest's FP context and unconditionally forward to the
540 	 * slow path for handling (i.e. return false).
541 	 */
542 	kvm_hyp_handle_fpsimd(vcpu, exit_code);
543 	return false;
544 }
545 
546 static bool kvm_hyp_handle_sysreg_vhe(struct kvm_vcpu *vcpu, u64 *exit_code)
547 {
548 	if (kvm_hyp_handle_tlbi_el2(vcpu, exit_code))
549 		return true;
550 
551 	if (kvm_hyp_handle_timer(vcpu, exit_code))
552 		return true;
553 
554 	if (kvm_hyp_handle_cpacr_el1(vcpu, exit_code))
555 		return true;
556 
557 	if (kvm_hyp_handle_zcr_el2(vcpu, exit_code))
558 		return true;
559 
560 	return kvm_hyp_handle_sysreg(vcpu, exit_code);
561 }
562 
563 static bool kvm_hyp_handle_impdef(struct kvm_vcpu *vcpu, u64 *exit_code)
564 {
565 	u64 iss;
566 
567 	if (!cpus_have_final_cap(ARM64_WORKAROUND_PMUV3_IMPDEF_TRAPS))
568 		return false;
569 
570 	/*
571 	 * Compute a synthetic ESR for a sysreg trap. Conveniently, AFSR1_EL2
572 	 * is populated with a correct ISS for a sysreg trap. These fruity
573 	 * parts are 64bit only, so unconditionally set IL.
574 	 */
575 	iss = ESR_ELx_ISS(read_sysreg_s(SYS_AFSR1_EL2));
576 	vcpu->arch.fault.esr_el2 = FIELD_PREP(ESR_ELx_EC_MASK, ESR_ELx_EC_SYS64) |
577 				   FIELD_PREP(ESR_ELx_ISS_MASK, iss) |
578 				   ESR_ELx_IL;
579 	return false;
580 }
581 
582 static const exit_handler_fn hyp_exit_handlers[] = {
583 	[0 ... ESR_ELx_EC_MAX]		= NULL,
584 	[ESR_ELx_EC_CP15_32]		= kvm_hyp_handle_cp15_32,
585 	[ESR_ELx_EC_SYS64]		= kvm_hyp_handle_sysreg_vhe,
586 	[ESR_ELx_EC_SVE]		= kvm_hyp_handle_fpsimd,
587 	[ESR_ELx_EC_FP_ASIMD]		= kvm_hyp_handle_fpsimd,
588 	[ESR_ELx_EC_IABT_LOW]		= kvm_hyp_handle_iabt_low,
589 	[ESR_ELx_EC_DABT_LOW]		= kvm_hyp_handle_dabt_low,
590 	[ESR_ELx_EC_WATCHPT_LOW]	= kvm_hyp_handle_watchpt_low,
591 	[ESR_ELx_EC_ERET]		= kvm_hyp_handle_eret,
592 	[ESR_ELx_EC_MOPS]		= kvm_hyp_handle_mops,
593 
594 	/* Apple shenanigans */
595 	[0x3F]				= kvm_hyp_handle_impdef,
596 };
597 
598 static inline bool fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
599 {
600 	synchronize_vcpu_pstate(vcpu, exit_code);
601 
602 	/*
603 	 * If we were in HYP context on entry, adjust the PSTATE view
604 	 * so that the usual helpers work correctly. This enforces our
605 	 * invariant that the guest's HYP context status is preserved
606 	 * across a run.
607 	 */
608 	if (vcpu_has_nv(vcpu) &&
609 	    unlikely(host_data_test_flag(VCPU_IN_HYP_CONTEXT))) {
610 		u64 mode = *vcpu_cpsr(vcpu) & (PSR_MODE_MASK | PSR_MODE32_BIT);
611 
612 		switch (mode) {
613 		case PSR_MODE_EL1t:
614 			mode = PSR_MODE_EL2t;
615 			break;
616 		case PSR_MODE_EL1h:
617 			mode = PSR_MODE_EL2h;
618 			break;
619 		}
620 
621 		*vcpu_cpsr(vcpu) &= ~(PSR_MODE_MASK | PSR_MODE32_BIT);
622 		*vcpu_cpsr(vcpu) |= mode;
623 	}
624 
625 	/* Apply extreme paranoia! */
626 	BUG_ON(vcpu_has_nv(vcpu) &&
627 	       !!host_data_test_flag(VCPU_IN_HYP_CONTEXT) != is_hyp_ctxt(vcpu));
628 
629 	return __fixup_guest_exit(vcpu, exit_code, hyp_exit_handlers);
630 }
631 
632 /* Switch to the guest for VHE systems running in EL2 */
633 static int __kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
634 {
635 	struct kvm_cpu_context *host_ctxt;
636 	struct kvm_cpu_context *guest_ctxt;
637 	u64 exit_code;
638 
639 	host_ctxt = host_data_ptr(host_ctxt);
640 	guest_ctxt = &vcpu->arch.ctxt;
641 
642 	sysreg_save_host_state_vhe(host_ctxt);
643 
644 	fpsimd_lazy_switch_to_guest(vcpu);
645 
646 	/*
647 	 * Note that ARM erratum 1165522 requires us to configure both stage 1
648 	 * and stage 2 translation for the guest context before we clear
649 	 * HCR_EL2.TGE. The stage 1 and stage 2 guest context has already been
650 	 * loaded on the CPU in kvm_vcpu_load_vhe().
651 	 */
652 	__activate_traps(vcpu);
653 
654 	__kvm_adjust_pc(vcpu);
655 
656 	sysreg_restore_guest_state_vhe(guest_ctxt);
657 	__debug_switch_to_guest(vcpu);
658 
659 	do {
660 		/* Jump in the fire! */
661 		exit_code = __guest_enter(vcpu);
662 
663 		/* And we're baaack! */
664 	} while (fixup_guest_exit(vcpu, &exit_code));
665 
666 	sysreg_save_guest_state_vhe(guest_ctxt);
667 
668 	__deactivate_traps(vcpu);
669 
670 	fpsimd_lazy_switch_to_host(vcpu);
671 
672 	sysreg_restore_host_state_vhe(host_ctxt);
673 
674 	if (guest_owns_fp_regs())
675 		__fpsimd_save_fpexc32(vcpu);
676 
677 	__debug_switch_to_host(vcpu);
678 
679 	return exit_code;
680 }
681 NOKPROBE_SYMBOL(__kvm_vcpu_run_vhe);
682 
683 int __kvm_vcpu_run(struct kvm_vcpu *vcpu)
684 {
685 	int ret;
686 
687 	local_daif_mask();
688 
689 	/*
690 	 * Having IRQs masked via PMR when entering the guest means the GIC
691 	 * will not signal the CPU of interrupts of lower priority, and the
692 	 * only way to get out will be via guest exceptions.
693 	 * Naturally, we want to avoid this.
694 	 *
695 	 * local_daif_mask() already sets GIC_PRIO_PSR_I_SET, we just need a
696 	 * dsb to ensure the redistributor is forwards EL2 IRQs to the CPU.
697 	 */
698 	pmr_sync();
699 
700 	ret = __kvm_vcpu_run_vhe(vcpu);
701 
702 	/*
703 	 * local_daif_restore() takes care to properly restore PSTATE.DAIF
704 	 * and the GIC PMR if the host is using IRQ priorities.
705 	 */
706 	local_daif_restore(DAIF_PROCCTX_NOIRQ);
707 
708 	/*
709 	 * When we exit from the guest we change a number of CPU configuration
710 	 * parameters, such as traps.  We rely on the isb() in kvm_call_hyp*()
711 	 * to make sure these changes take effect before running the host or
712 	 * additional guests.
713 	 */
714 	return ret;
715 }
716 
717 static void __noreturn __hyp_call_panic(u64 spsr, u64 elr, u64 par)
718 {
719 	struct kvm_cpu_context *host_ctxt;
720 	struct kvm_vcpu *vcpu;
721 
722 	host_ctxt = host_data_ptr(host_ctxt);
723 	vcpu = host_ctxt->__hyp_running_vcpu;
724 
725 	__deactivate_traps(vcpu);
726 	sysreg_restore_host_state_vhe(host_ctxt);
727 
728 	panic("HYP panic:\nPS:%08llx PC:%016llx ESR:%08llx\nFAR:%016llx HPFAR:%016llx PAR:%016llx\nVCPU:%p\n",
729 	      spsr, elr,
730 	      read_sysreg_el2(SYS_ESR), read_sysreg_el2(SYS_FAR),
731 	      read_sysreg(hpfar_el2), par, vcpu);
732 }
733 NOKPROBE_SYMBOL(__hyp_call_panic);
734 
735 void __noreturn hyp_panic(void)
736 {
737 	u64 spsr = read_sysreg_el2(SYS_SPSR);
738 	u64 elr = read_sysreg_el2(SYS_ELR);
739 	u64 par = read_sysreg_par();
740 
741 	__hyp_call_panic(spsr, elr, par);
742 }
743 
744 asmlinkage void kvm_unexpected_el2_exception(void)
745 {
746 	__kvm_unexpected_el2_exception();
747 }
748