xref: /linux/arch/loongarch/kvm/exit.c (revision 1553a1c48281243359a9529a10ddb551f3b967ab)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
4  */
5 
6 #include <linux/err.h>
7 #include <linux/errno.h>
8 #include <linux/kvm_host.h>
9 #include <linux/module.h>
10 #include <linux/preempt.h>
11 #include <linux/vmalloc.h>
12 #include <asm/fpu.h>
13 #include <asm/inst.h>
14 #include <asm/loongarch.h>
15 #include <asm/mmzone.h>
16 #include <asm/numa.h>
17 #include <asm/time.h>
18 #include <asm/tlb.h>
19 #include <asm/kvm_csr.h>
20 #include <asm/kvm_vcpu.h>
21 #include "trace.h"
22 
23 static unsigned long kvm_emu_read_csr(struct kvm_vcpu *vcpu, int csrid)
24 {
25 	unsigned long val = 0;
26 	struct loongarch_csrs *csr = vcpu->arch.csr;
27 
28 	/*
29 	 * From LoongArch Reference Manual Volume 1 Chapter 4.2.1
30 	 * For undefined CSR id, return value is 0
31 	 */
32 	if (get_gcsr_flag(csrid) & SW_GCSR)
33 		val = kvm_read_sw_gcsr(csr, csrid);
34 	else
35 		pr_warn_once("Unsupported csrrd 0x%x with pc %lx\n", csrid, vcpu->arch.pc);
36 
37 	return val;
38 }
39 
40 static unsigned long kvm_emu_write_csr(struct kvm_vcpu *vcpu, int csrid, unsigned long val)
41 {
42 	unsigned long old = 0;
43 	struct loongarch_csrs *csr = vcpu->arch.csr;
44 
45 	if (get_gcsr_flag(csrid) & SW_GCSR) {
46 		old = kvm_read_sw_gcsr(csr, csrid);
47 		kvm_write_sw_gcsr(csr, csrid, val);
48 	} else
49 		pr_warn_once("Unsupported csrwr 0x%x with pc %lx\n", csrid, vcpu->arch.pc);
50 
51 	return old;
52 }
53 
54 static unsigned long kvm_emu_xchg_csr(struct kvm_vcpu *vcpu, int csrid,
55 				unsigned long csr_mask, unsigned long val)
56 {
57 	unsigned long old = 0;
58 	struct loongarch_csrs *csr = vcpu->arch.csr;
59 
60 	if (get_gcsr_flag(csrid) & SW_GCSR) {
61 		old = kvm_read_sw_gcsr(csr, csrid);
62 		val = (old & ~csr_mask) | (val & csr_mask);
63 		kvm_write_sw_gcsr(csr, csrid, val);
64 		old = old & csr_mask;
65 	} else
66 		pr_warn_once("Unsupported csrxchg 0x%x with pc %lx\n", csrid, vcpu->arch.pc);
67 
68 	return old;
69 }
70 
71 static int kvm_handle_csr(struct kvm_vcpu *vcpu, larch_inst inst)
72 {
73 	unsigned int rd, rj, csrid;
74 	unsigned long csr_mask, val = 0;
75 
76 	/*
77 	 * CSR value mask imm
78 	 * rj = 0 means csrrd
79 	 * rj = 1 means csrwr
80 	 * rj != 0,1 means csrxchg
81 	 */
82 	rd = inst.reg2csr_format.rd;
83 	rj = inst.reg2csr_format.rj;
84 	csrid = inst.reg2csr_format.csr;
85 
86 	/* Process CSR ops */
87 	switch (rj) {
88 	case 0: /* process csrrd */
89 		val = kvm_emu_read_csr(vcpu, csrid);
90 		vcpu->arch.gprs[rd] = val;
91 		break;
92 	case 1: /* process csrwr */
93 		val = vcpu->arch.gprs[rd];
94 		val = kvm_emu_write_csr(vcpu, csrid, val);
95 		vcpu->arch.gprs[rd] = val;
96 		break;
97 	default: /* process csrxchg */
98 		val = vcpu->arch.gprs[rd];
99 		csr_mask = vcpu->arch.gprs[rj];
100 		val = kvm_emu_xchg_csr(vcpu, csrid, csr_mask, val);
101 		vcpu->arch.gprs[rd] = val;
102 	}
103 
104 	return EMULATE_DONE;
105 }
106 
107 int kvm_emu_iocsr(larch_inst inst, struct kvm_run *run, struct kvm_vcpu *vcpu)
108 {
109 	int ret;
110 	unsigned long val;
111 	u32 addr, rd, rj, opcode;
112 
113 	/*
114 	 * Each IOCSR with different opcode
115 	 */
116 	rd = inst.reg2_format.rd;
117 	rj = inst.reg2_format.rj;
118 	opcode = inst.reg2_format.opcode;
119 	addr = vcpu->arch.gprs[rj];
120 	ret = EMULATE_DO_IOCSR;
121 	run->iocsr_io.phys_addr = addr;
122 	run->iocsr_io.is_write = 0;
123 
124 	/* LoongArch is Little endian */
125 	switch (opcode) {
126 	case iocsrrdb_op:
127 		run->iocsr_io.len = 1;
128 		break;
129 	case iocsrrdh_op:
130 		run->iocsr_io.len = 2;
131 		break;
132 	case iocsrrdw_op:
133 		run->iocsr_io.len = 4;
134 		break;
135 	case iocsrrdd_op:
136 		run->iocsr_io.len = 8;
137 		break;
138 	case iocsrwrb_op:
139 		run->iocsr_io.len = 1;
140 		run->iocsr_io.is_write = 1;
141 		break;
142 	case iocsrwrh_op:
143 		run->iocsr_io.len = 2;
144 		run->iocsr_io.is_write = 1;
145 		break;
146 	case iocsrwrw_op:
147 		run->iocsr_io.len = 4;
148 		run->iocsr_io.is_write = 1;
149 		break;
150 	case iocsrwrd_op:
151 		run->iocsr_io.len = 8;
152 		run->iocsr_io.is_write = 1;
153 		break;
154 	default:
155 		ret = EMULATE_FAIL;
156 		break;
157 	}
158 
159 	if (ret == EMULATE_DO_IOCSR) {
160 		if (run->iocsr_io.is_write) {
161 			val = vcpu->arch.gprs[rd];
162 			memcpy(run->iocsr_io.data, &val, run->iocsr_io.len);
163 		}
164 		vcpu->arch.io_gpr = rd;
165 	}
166 
167 	return ret;
168 }
169 
170 int kvm_complete_iocsr_read(struct kvm_vcpu *vcpu, struct kvm_run *run)
171 {
172 	enum emulation_result er = EMULATE_DONE;
173 	unsigned long *gpr = &vcpu->arch.gprs[vcpu->arch.io_gpr];
174 
175 	switch (run->iocsr_io.len) {
176 	case 1:
177 		*gpr = *(s8 *)run->iocsr_io.data;
178 		break;
179 	case 2:
180 		*gpr = *(s16 *)run->iocsr_io.data;
181 		break;
182 	case 4:
183 		*gpr = *(s32 *)run->iocsr_io.data;
184 		break;
185 	case 8:
186 		*gpr = *(s64 *)run->iocsr_io.data;
187 		break;
188 	default:
189 		kvm_err("Bad IOCSR length: %d, addr is 0x%lx\n",
190 				run->iocsr_io.len, vcpu->arch.badv);
191 		er = EMULATE_FAIL;
192 		break;
193 	}
194 
195 	return er;
196 }
197 
198 int kvm_emu_idle(struct kvm_vcpu *vcpu)
199 {
200 	++vcpu->stat.idle_exits;
201 	trace_kvm_exit_idle(vcpu, KVM_TRACE_EXIT_IDLE);
202 
203 	if (!kvm_arch_vcpu_runnable(vcpu))
204 		kvm_vcpu_halt(vcpu);
205 
206 	return EMULATE_DONE;
207 }
208 
209 static int kvm_trap_handle_gspr(struct kvm_vcpu *vcpu)
210 {
211 	int rd, rj;
212 	unsigned int index;
213 	unsigned long curr_pc;
214 	larch_inst inst;
215 	enum emulation_result er = EMULATE_DONE;
216 	struct kvm_run *run = vcpu->run;
217 
218 	/* Fetch the instruction */
219 	inst.word = vcpu->arch.badi;
220 	curr_pc = vcpu->arch.pc;
221 	update_pc(&vcpu->arch);
222 
223 	trace_kvm_exit_gspr(vcpu, inst.word);
224 	er = EMULATE_FAIL;
225 	switch (((inst.word >> 24) & 0xff)) {
226 	case 0x0: /* CPUCFG GSPR */
227 		if (inst.reg2_format.opcode == 0x1B) {
228 			rd = inst.reg2_format.rd;
229 			rj = inst.reg2_format.rj;
230 			++vcpu->stat.cpucfg_exits;
231 			index = vcpu->arch.gprs[rj];
232 			er = EMULATE_DONE;
233 			/*
234 			 * By LoongArch Reference Manual 2.2.10.5
235 			 * return value is 0 for undefined cpucfg index
236 			 */
237 			if (index < KVM_MAX_CPUCFG_REGS)
238 				vcpu->arch.gprs[rd] = vcpu->arch.cpucfg[index];
239 			else
240 				vcpu->arch.gprs[rd] = 0;
241 		}
242 		break;
243 	case 0x4: /* CSR{RD,WR,XCHG} GSPR */
244 		er = kvm_handle_csr(vcpu, inst);
245 		break;
246 	case 0x6: /* Cache, Idle and IOCSR GSPR */
247 		switch (((inst.word >> 22) & 0x3ff)) {
248 		case 0x18: /* Cache GSPR */
249 			er = EMULATE_DONE;
250 			trace_kvm_exit_cache(vcpu, KVM_TRACE_EXIT_CACHE);
251 			break;
252 		case 0x19: /* Idle/IOCSR GSPR */
253 			switch (((inst.word >> 15) & 0x1ffff)) {
254 			case 0xc90: /* IOCSR GSPR */
255 				er = kvm_emu_iocsr(inst, run, vcpu);
256 				break;
257 			case 0xc91: /* Idle GSPR */
258 				er = kvm_emu_idle(vcpu);
259 				break;
260 			default:
261 				er = EMULATE_FAIL;
262 				break;
263 			}
264 			break;
265 		default:
266 			er = EMULATE_FAIL;
267 			break;
268 		}
269 		break;
270 	default:
271 		er = EMULATE_FAIL;
272 		break;
273 	}
274 
275 	/* Rollback PC only if emulation was unsuccessful */
276 	if (er == EMULATE_FAIL) {
277 		kvm_err("[%#lx]%s: unsupported gspr instruction 0x%08x\n",
278 			curr_pc, __func__, inst.word);
279 
280 		kvm_arch_vcpu_dump_regs(vcpu);
281 		vcpu->arch.pc = curr_pc;
282 	}
283 
284 	return er;
285 }
286 
287 /*
288  * Trigger GSPR:
289  * 1) Execute CPUCFG instruction;
290  * 2) Execute CACOP/IDLE instructions;
291  * 3) Access to unimplemented CSRs/IOCSRs.
292  */
293 static int kvm_handle_gspr(struct kvm_vcpu *vcpu)
294 {
295 	int ret = RESUME_GUEST;
296 	enum emulation_result er = EMULATE_DONE;
297 
298 	er = kvm_trap_handle_gspr(vcpu);
299 
300 	if (er == EMULATE_DONE) {
301 		ret = RESUME_GUEST;
302 	} else if (er == EMULATE_DO_MMIO) {
303 		vcpu->run->exit_reason = KVM_EXIT_MMIO;
304 		ret = RESUME_HOST;
305 	} else if (er == EMULATE_DO_IOCSR) {
306 		vcpu->run->exit_reason = KVM_EXIT_LOONGARCH_IOCSR;
307 		ret = RESUME_HOST;
308 	} else {
309 		kvm_queue_exception(vcpu, EXCCODE_INE, 0);
310 		ret = RESUME_GUEST;
311 	}
312 
313 	return ret;
314 }
315 
316 int kvm_emu_mmio_read(struct kvm_vcpu *vcpu, larch_inst inst)
317 {
318 	int ret;
319 	unsigned int op8, opcode, rd;
320 	struct kvm_run *run = vcpu->run;
321 
322 	run->mmio.phys_addr = vcpu->arch.badv;
323 	vcpu->mmio_needed = 2;	/* signed */
324 	op8 = (inst.word >> 24) & 0xff;
325 	ret = EMULATE_DO_MMIO;
326 
327 	switch (op8) {
328 	case 0x24 ... 0x27:	/* ldptr.w/d process */
329 		rd = inst.reg2i14_format.rd;
330 		opcode = inst.reg2i14_format.opcode;
331 
332 		switch (opcode) {
333 		case ldptrw_op:
334 			run->mmio.len = 4;
335 			break;
336 		case ldptrd_op:
337 			run->mmio.len = 8;
338 			break;
339 		default:
340 			break;
341 		}
342 		break;
343 	case 0x28 ... 0x2e:	/* ld.b/h/w/d, ld.bu/hu/wu process */
344 		rd = inst.reg2i12_format.rd;
345 		opcode = inst.reg2i12_format.opcode;
346 
347 		switch (opcode) {
348 		case ldb_op:
349 			run->mmio.len = 1;
350 			break;
351 		case ldbu_op:
352 			vcpu->mmio_needed = 1;	/* unsigned */
353 			run->mmio.len = 1;
354 			break;
355 		case ldh_op:
356 			run->mmio.len = 2;
357 			break;
358 		case ldhu_op:
359 			vcpu->mmio_needed = 1;	/* unsigned */
360 			run->mmio.len = 2;
361 			break;
362 		case ldw_op:
363 			run->mmio.len = 4;
364 			break;
365 		case ldwu_op:
366 			vcpu->mmio_needed = 1;	/* unsigned */
367 			run->mmio.len = 4;
368 			break;
369 		case ldd_op:
370 			run->mmio.len = 8;
371 			break;
372 		default:
373 			ret = EMULATE_FAIL;
374 			break;
375 		}
376 		break;
377 	case 0x38:	/* ldx.b/h/w/d, ldx.bu/hu/wu process */
378 		rd = inst.reg3_format.rd;
379 		opcode = inst.reg3_format.opcode;
380 
381 		switch (opcode) {
382 		case ldxb_op:
383 			run->mmio.len = 1;
384 			break;
385 		case ldxbu_op:
386 			run->mmio.len = 1;
387 			vcpu->mmio_needed = 1;	/* unsigned */
388 			break;
389 		case ldxh_op:
390 			run->mmio.len = 2;
391 			break;
392 		case ldxhu_op:
393 			run->mmio.len = 2;
394 			vcpu->mmio_needed = 1;	/* unsigned */
395 			break;
396 		case ldxw_op:
397 			run->mmio.len = 4;
398 			break;
399 		case ldxwu_op:
400 			run->mmio.len = 4;
401 			vcpu->mmio_needed = 1;	/* unsigned */
402 			break;
403 		case ldxd_op:
404 			run->mmio.len = 8;
405 			break;
406 		default:
407 			ret = EMULATE_FAIL;
408 			break;
409 		}
410 		break;
411 	default:
412 		ret = EMULATE_FAIL;
413 	}
414 
415 	if (ret == EMULATE_DO_MMIO) {
416 		/* Set for kvm_complete_mmio_read() use */
417 		vcpu->arch.io_gpr = rd;
418 		run->mmio.is_write = 0;
419 		vcpu->mmio_is_write = 0;
420 	} else {
421 		kvm_err("Read not supported Inst=0x%08x @%lx BadVaddr:%#lx\n",
422 			inst.word, vcpu->arch.pc, vcpu->arch.badv);
423 		kvm_arch_vcpu_dump_regs(vcpu);
424 		vcpu->mmio_needed = 0;
425 	}
426 
427 	return ret;
428 }
429 
430 int kvm_complete_mmio_read(struct kvm_vcpu *vcpu, struct kvm_run *run)
431 {
432 	enum emulation_result er = EMULATE_DONE;
433 	unsigned long *gpr = &vcpu->arch.gprs[vcpu->arch.io_gpr];
434 
435 	/* Update with new PC */
436 	update_pc(&vcpu->arch);
437 	switch (run->mmio.len) {
438 	case 1:
439 		if (vcpu->mmio_needed == 2)
440 			*gpr = *(s8 *)run->mmio.data;
441 		else
442 			*gpr = *(u8 *)run->mmio.data;
443 		break;
444 	case 2:
445 		if (vcpu->mmio_needed == 2)
446 			*gpr = *(s16 *)run->mmio.data;
447 		else
448 			*gpr = *(u16 *)run->mmio.data;
449 		break;
450 	case 4:
451 		if (vcpu->mmio_needed == 2)
452 			*gpr = *(s32 *)run->mmio.data;
453 		else
454 			*gpr = *(u32 *)run->mmio.data;
455 		break;
456 	case 8:
457 		*gpr = *(s64 *)run->mmio.data;
458 		break;
459 	default:
460 		kvm_err("Bad MMIO length: %d, addr is 0x%lx\n",
461 				run->mmio.len, vcpu->arch.badv);
462 		er = EMULATE_FAIL;
463 		break;
464 	}
465 
466 	return er;
467 }
468 
469 int kvm_emu_mmio_write(struct kvm_vcpu *vcpu, larch_inst inst)
470 {
471 	int ret;
472 	unsigned int rd, op8, opcode;
473 	unsigned long curr_pc, rd_val = 0;
474 	struct kvm_run *run = vcpu->run;
475 	void *data = run->mmio.data;
476 
477 	/*
478 	 * Update PC and hold onto current PC in case there is
479 	 * an error and we want to rollback the PC
480 	 */
481 	curr_pc = vcpu->arch.pc;
482 	update_pc(&vcpu->arch);
483 
484 	op8 = (inst.word >> 24) & 0xff;
485 	run->mmio.phys_addr = vcpu->arch.badv;
486 	ret = EMULATE_DO_MMIO;
487 	switch (op8) {
488 	case 0x24 ... 0x27:	/* stptr.w/d process */
489 		rd = inst.reg2i14_format.rd;
490 		opcode = inst.reg2i14_format.opcode;
491 
492 		switch (opcode) {
493 		case stptrw_op:
494 			run->mmio.len = 4;
495 			*(unsigned int *)data = vcpu->arch.gprs[rd];
496 			break;
497 		case stptrd_op:
498 			run->mmio.len = 8;
499 			*(unsigned long *)data = vcpu->arch.gprs[rd];
500 			break;
501 		default:
502 			ret = EMULATE_FAIL;
503 			break;
504 		}
505 		break;
506 	case 0x28 ... 0x2e:	/* st.b/h/w/d  process */
507 		rd = inst.reg2i12_format.rd;
508 		opcode = inst.reg2i12_format.opcode;
509 		rd_val = vcpu->arch.gprs[rd];
510 
511 		switch (opcode) {
512 		case stb_op:
513 			run->mmio.len = 1;
514 			*(unsigned char *)data = rd_val;
515 			break;
516 		case sth_op:
517 			run->mmio.len = 2;
518 			*(unsigned short *)data = rd_val;
519 			break;
520 		case stw_op:
521 			run->mmio.len = 4;
522 			*(unsigned int *)data = rd_val;
523 			break;
524 		case std_op:
525 			run->mmio.len = 8;
526 			*(unsigned long *)data = rd_val;
527 			break;
528 		default:
529 			ret = EMULATE_FAIL;
530 			break;
531 		}
532 		break;
533 	case 0x38:	/* stx.b/h/w/d process */
534 		rd = inst.reg3_format.rd;
535 		opcode = inst.reg3_format.opcode;
536 
537 		switch (opcode) {
538 		case stxb_op:
539 			run->mmio.len = 1;
540 			*(unsigned char *)data = vcpu->arch.gprs[rd];
541 			break;
542 		case stxh_op:
543 			run->mmio.len = 2;
544 			*(unsigned short *)data = vcpu->arch.gprs[rd];
545 			break;
546 		case stxw_op:
547 			run->mmio.len = 4;
548 			*(unsigned int *)data = vcpu->arch.gprs[rd];
549 			break;
550 		case stxd_op:
551 			run->mmio.len = 8;
552 			*(unsigned long *)data = vcpu->arch.gprs[rd];
553 			break;
554 		default:
555 			ret = EMULATE_FAIL;
556 			break;
557 		}
558 		break;
559 	default:
560 		ret = EMULATE_FAIL;
561 	}
562 
563 	if (ret == EMULATE_DO_MMIO) {
564 		run->mmio.is_write = 1;
565 		vcpu->mmio_needed = 1;
566 		vcpu->mmio_is_write = 1;
567 	} else {
568 		vcpu->arch.pc = curr_pc;
569 		kvm_err("Write not supported Inst=0x%08x @%lx BadVaddr:%#lx\n",
570 			inst.word, vcpu->arch.pc, vcpu->arch.badv);
571 		kvm_arch_vcpu_dump_regs(vcpu);
572 		/* Rollback PC if emulation was unsuccessful */
573 	}
574 
575 	return ret;
576 }
577 
578 static int kvm_handle_rdwr_fault(struct kvm_vcpu *vcpu, bool write)
579 {
580 	int ret;
581 	larch_inst inst;
582 	enum emulation_result er = EMULATE_DONE;
583 	struct kvm_run *run = vcpu->run;
584 	unsigned long badv = vcpu->arch.badv;
585 
586 	ret = kvm_handle_mm_fault(vcpu, badv, write);
587 	if (ret) {
588 		/* Treat as MMIO */
589 		inst.word = vcpu->arch.badi;
590 		if (write) {
591 			er = kvm_emu_mmio_write(vcpu, inst);
592 		} else {
593 			/* A code fetch fault doesn't count as an MMIO */
594 			if (kvm_is_ifetch_fault(&vcpu->arch)) {
595 				kvm_queue_exception(vcpu, EXCCODE_ADE, EXSUBCODE_ADEF);
596 				return RESUME_GUEST;
597 			}
598 
599 			er = kvm_emu_mmio_read(vcpu, inst);
600 		}
601 	}
602 
603 	if (er == EMULATE_DONE) {
604 		ret = RESUME_GUEST;
605 	} else if (er == EMULATE_DO_MMIO) {
606 		run->exit_reason = KVM_EXIT_MMIO;
607 		ret = RESUME_HOST;
608 	} else {
609 		kvm_queue_exception(vcpu, EXCCODE_ADE, EXSUBCODE_ADEM);
610 		ret = RESUME_GUEST;
611 	}
612 
613 	return ret;
614 }
615 
616 static int kvm_handle_read_fault(struct kvm_vcpu *vcpu)
617 {
618 	return kvm_handle_rdwr_fault(vcpu, false);
619 }
620 
621 static int kvm_handle_write_fault(struct kvm_vcpu *vcpu)
622 {
623 	return kvm_handle_rdwr_fault(vcpu, true);
624 }
625 
626 /**
627  * kvm_handle_fpu_disabled() - Guest used fpu however it is disabled at host
628  * @vcpu:	Virtual CPU context.
629  *
630  * Handle when the guest attempts to use fpu which hasn't been allowed
631  * by the root context.
632  */
633 static int kvm_handle_fpu_disabled(struct kvm_vcpu *vcpu)
634 {
635 	struct kvm_run *run = vcpu->run;
636 
637 	if (!kvm_guest_has_fpu(&vcpu->arch)) {
638 		kvm_queue_exception(vcpu, EXCCODE_INE, 0);
639 		return RESUME_GUEST;
640 	}
641 
642 	/*
643 	 * If guest FPU not present, the FPU operation should have been
644 	 * treated as a reserved instruction!
645 	 * If FPU already in use, we shouldn't get this at all.
646 	 */
647 	if (WARN_ON(vcpu->arch.aux_inuse & KVM_LARCH_FPU)) {
648 		kvm_err("%s internal error\n", __func__);
649 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
650 		return RESUME_HOST;
651 	}
652 
653 	kvm_own_fpu(vcpu);
654 
655 	return RESUME_GUEST;
656 }
657 
658 /*
659  * kvm_handle_lsx_disabled() - Guest used LSX while disabled in root.
660  * @vcpu:      Virtual CPU context.
661  *
662  * Handle when the guest attempts to use LSX when it is disabled in the root
663  * context.
664  */
665 static int kvm_handle_lsx_disabled(struct kvm_vcpu *vcpu)
666 {
667 	if (kvm_own_lsx(vcpu))
668 		kvm_queue_exception(vcpu, EXCCODE_INE, 0);
669 
670 	return RESUME_GUEST;
671 }
672 
673 /*
674  * kvm_handle_lasx_disabled() - Guest used LASX while disabled in root.
675  * @vcpu:	Virtual CPU context.
676  *
677  * Handle when the guest attempts to use LASX when it is disabled in the root
678  * context.
679  */
680 static int kvm_handle_lasx_disabled(struct kvm_vcpu *vcpu)
681 {
682 	if (kvm_own_lasx(vcpu))
683 		kvm_queue_exception(vcpu, EXCCODE_INE, 0);
684 
685 	return RESUME_GUEST;
686 }
687 
688 /*
689  * LoongArch KVM callback handling for unimplemented guest exiting
690  */
691 static int kvm_fault_ni(struct kvm_vcpu *vcpu)
692 {
693 	unsigned int ecode, inst;
694 	unsigned long estat, badv;
695 
696 	/* Fetch the instruction */
697 	inst = vcpu->arch.badi;
698 	badv = vcpu->arch.badv;
699 	estat = vcpu->arch.host_estat;
700 	ecode = (estat & CSR_ESTAT_EXC) >> CSR_ESTAT_EXC_SHIFT;
701 	kvm_err("ECode: %d PC=%#lx Inst=0x%08x BadVaddr=%#lx ESTAT=%#lx\n",
702 			ecode, vcpu->arch.pc, inst, badv, read_gcsr_estat());
703 	kvm_arch_vcpu_dump_regs(vcpu);
704 	kvm_queue_exception(vcpu, EXCCODE_INE, 0);
705 
706 	return RESUME_GUEST;
707 }
708 
709 static exit_handle_fn kvm_fault_tables[EXCCODE_INT_START] = {
710 	[0 ... EXCCODE_INT_START - 1]	= kvm_fault_ni,
711 	[EXCCODE_TLBI]			= kvm_handle_read_fault,
712 	[EXCCODE_TLBL]			= kvm_handle_read_fault,
713 	[EXCCODE_TLBS]			= kvm_handle_write_fault,
714 	[EXCCODE_TLBM]			= kvm_handle_write_fault,
715 	[EXCCODE_FPDIS]			= kvm_handle_fpu_disabled,
716 	[EXCCODE_LSXDIS]		= kvm_handle_lsx_disabled,
717 	[EXCCODE_LASXDIS]		= kvm_handle_lasx_disabled,
718 	[EXCCODE_GSPR]			= kvm_handle_gspr,
719 };
720 
721 int kvm_handle_fault(struct kvm_vcpu *vcpu, int fault)
722 {
723 	return kvm_fault_tables[fault](vcpu);
724 }
725