1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * set_id_regs - Test for setting ID register from usersapce.
4  *
5  * Copyright (c) 2023 Google LLC.
6  *
7  *
8  * Test that KVM supports setting ID registers from userspace and handles the
9  * feature set correctly.
10  */
11 
12 #include <stdint.h>
13 #include "kvm_util.h"
14 #include "processor.h"
15 #include "test_util.h"
16 #include <linux/bitfield.h>
17 
18 enum ftr_type {
19 	FTR_EXACT,			/* Use a predefined safe value */
20 	FTR_LOWER_SAFE,			/* Smaller value is safe */
21 	FTR_HIGHER_SAFE,		/* Bigger value is safe */
22 	FTR_HIGHER_OR_ZERO_SAFE,	/* Bigger value is safe, but 0 is biggest */
23 	FTR_END,			/* Mark the last ftr bits */
24 };
25 
26 #define FTR_SIGNED	true	/* Value should be treated as signed */
27 #define FTR_UNSIGNED	false	/* Value should be treated as unsigned */
28 
29 struct reg_ftr_bits {
30 	char *name;
31 	bool sign;
32 	enum ftr_type type;
33 	uint8_t shift;
34 	uint64_t mask;
35 	/*
36 	 * For FTR_EXACT, safe_val is used as the exact safe value.
37 	 * For FTR_LOWER_SAFE, safe_val is used as the minimal safe value.
38 	 */
39 	int64_t safe_val;
40 };
41 
42 struct test_feature_reg {
43 	uint32_t reg;
44 	const struct reg_ftr_bits *ftr_bits;
45 };
46 
47 #define __REG_FTR_BITS(NAME, SIGNED, TYPE, SHIFT, MASK, SAFE_VAL)	\
48 	{								\
49 		.name = #NAME,						\
50 		.sign = SIGNED,						\
51 		.type = TYPE,						\
52 		.shift = SHIFT,						\
53 		.mask = MASK,						\
54 		.safe_val = SAFE_VAL,					\
55 	}
56 
57 #define REG_FTR_BITS(type, reg, field, safe_val) \
58 	__REG_FTR_BITS(reg##_##field, FTR_UNSIGNED, type, reg##_##field##_SHIFT, \
59 		       reg##_##field##_MASK, safe_val)
60 
61 #define S_REG_FTR_BITS(type, reg, field, safe_val) \
62 	__REG_FTR_BITS(reg##_##field, FTR_SIGNED, type, reg##_##field##_SHIFT, \
63 		       reg##_##field##_MASK, safe_val)
64 
65 #define REG_FTR_END					\
66 	{						\
67 		.type = FTR_END,			\
68 	}
69 
70 static const struct reg_ftr_bits ftr_id_aa64dfr0_el1[] = {
71 	S_REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64DFR0_EL1, DoubleLock, 0),
72 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64DFR0_EL1, WRPs, 0),
73 	S_REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64DFR0_EL1, PMUVer, 0),
74 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64DFR0_EL1, DebugVer, ID_AA64DFR0_EL1_DebugVer_IMP),
75 	REG_FTR_END,
76 };
77 
78 static const struct reg_ftr_bits ftr_id_dfr0_el1[] = {
79 	S_REG_FTR_BITS(FTR_LOWER_SAFE, ID_DFR0_EL1, PerfMon, ID_DFR0_EL1_PerfMon_PMUv3),
80 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_DFR0_EL1, CopDbg, ID_DFR0_EL1_CopDbg_Armv8),
81 	REG_FTR_END,
82 };
83 
84 static const struct reg_ftr_bits ftr_id_aa64isar0_el1[] = {
85 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, RNDR, 0),
86 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, TLB, 0),
87 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, TS, 0),
88 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, FHM, 0),
89 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, DP, 0),
90 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, SM4, 0),
91 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, SM3, 0),
92 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, SHA3, 0),
93 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, RDM, 0),
94 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, TME, 0),
95 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, ATOMIC, 0),
96 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, CRC32, 0),
97 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, SHA2, 0),
98 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, SHA1, 0),
99 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, AES, 0),
100 	REG_FTR_END,
101 };
102 
103 static const struct reg_ftr_bits ftr_id_aa64isar1_el1[] = {
104 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, LS64, 0),
105 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, XS, 0),
106 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, I8MM, 0),
107 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, DGH, 0),
108 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, BF16, 0),
109 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, SPECRES, 0),
110 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, SB, 0),
111 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, FRINTTS, 0),
112 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, LRCPC, 0),
113 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, FCMA, 0),
114 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, JSCVT, 0),
115 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, DPB, 0),
116 	REG_FTR_END,
117 };
118 
119 static const struct reg_ftr_bits ftr_id_aa64isar2_el1[] = {
120 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR2_EL1, BC, 0),
121 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR2_EL1, RPRES, 0),
122 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR2_EL1, WFxT, 0),
123 	REG_FTR_END,
124 };
125 
126 static const struct reg_ftr_bits ftr_id_aa64pfr0_el1[] = {
127 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, CSV3, 0),
128 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, CSV2, 0),
129 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, DIT, 0),
130 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, SEL2, 0),
131 	REG_FTR_BITS(FTR_EXACT, ID_AA64PFR0_EL1, GIC, 0),
132 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, EL3, 1),
133 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, EL2, 1),
134 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, EL1, 1),
135 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, EL0, 1),
136 	REG_FTR_END,
137 };
138 
139 static const struct reg_ftr_bits ftr_id_aa64pfr1_el1[] = {
140 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR1_EL1, CSV2_frac, 0),
141 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR1_EL1, SSBS, ID_AA64PFR1_EL1_SSBS_NI),
142 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR1_EL1, BT, 0),
143 	REG_FTR_END,
144 };
145 
146 static const struct reg_ftr_bits ftr_id_aa64mmfr0_el1[] = {
147 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, ECV, 0),
148 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, EXS, 0),
149 	REG_FTR_BITS(FTR_EXACT, ID_AA64MMFR0_EL1, TGRAN4_2, 1),
150 	REG_FTR_BITS(FTR_EXACT, ID_AA64MMFR0_EL1, TGRAN64_2, 1),
151 	REG_FTR_BITS(FTR_EXACT, ID_AA64MMFR0_EL1, TGRAN16_2, 1),
152 	S_REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, TGRAN4, 0),
153 	S_REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, TGRAN64, 0),
154 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, TGRAN16, 0),
155 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, BIGENDEL0, 0),
156 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, SNSMEM, 0),
157 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, BIGEND, 0),
158 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, PARANGE, 0),
159 	REG_FTR_END,
160 };
161 
162 static const struct reg_ftr_bits ftr_id_aa64mmfr1_el1[] = {
163 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, TIDCP1, 0),
164 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, AFP, 0),
165 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, ETS, 0),
166 	REG_FTR_BITS(FTR_HIGHER_SAFE, ID_AA64MMFR1_EL1, SpecSEI, 0),
167 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, PAN, 0),
168 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, LO, 0),
169 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, HPDS, 0),
170 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, HAFDBS, 0),
171 	REG_FTR_END,
172 };
173 
174 static const struct reg_ftr_bits ftr_id_aa64mmfr2_el1[] = {
175 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, E0PD, 0),
176 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, BBM, 0),
177 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, TTL, 0),
178 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, AT, 0),
179 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, ST, 0),
180 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, VARange, 0),
181 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, IESB, 0),
182 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, LSM, 0),
183 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, UAO, 0),
184 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, CnP, 0),
185 	REG_FTR_END,
186 };
187 
188 static const struct reg_ftr_bits ftr_id_aa64zfr0_el1[] = {
189 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, F64MM, 0),
190 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, F32MM, 0),
191 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, I8MM, 0),
192 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, SM4, 0),
193 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, SHA3, 0),
194 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, BF16, 0),
195 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, BitPerm, 0),
196 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, AES, 0),
197 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, SVEver, 0),
198 	REG_FTR_END,
199 };
200 
201 #define TEST_REG(id, table)			\
202 	{					\
203 		.reg = id,			\
204 		.ftr_bits = &((table)[0]),	\
205 	}
206 
207 static struct test_feature_reg test_regs[] = {
208 	TEST_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0_el1),
209 	TEST_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0_el1),
210 	TEST_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0_el1),
211 	TEST_REG(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1_el1),
212 	TEST_REG(SYS_ID_AA64ISAR2_EL1, ftr_id_aa64isar2_el1),
213 	TEST_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0_el1),
214 	TEST_REG(SYS_ID_AA64PFR1_EL1, ftr_id_aa64pfr1_el1),
215 	TEST_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0_el1),
216 	TEST_REG(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1_el1),
217 	TEST_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2_el1),
218 	TEST_REG(SYS_ID_AA64ZFR0_EL1, ftr_id_aa64zfr0_el1),
219 };
220 
221 #define GUEST_REG_SYNC(id) GUEST_SYNC_ARGS(0, id, read_sysreg_s(id), 0, 0);
222 
guest_code(void)223 static void guest_code(void)
224 {
225 	GUEST_REG_SYNC(SYS_ID_AA64DFR0_EL1);
226 	GUEST_REG_SYNC(SYS_ID_DFR0_EL1);
227 	GUEST_REG_SYNC(SYS_ID_AA64ISAR0_EL1);
228 	GUEST_REG_SYNC(SYS_ID_AA64ISAR1_EL1);
229 	GUEST_REG_SYNC(SYS_ID_AA64ISAR2_EL1);
230 	GUEST_REG_SYNC(SYS_ID_AA64PFR0_EL1);
231 	GUEST_REG_SYNC(SYS_ID_AA64MMFR0_EL1);
232 	GUEST_REG_SYNC(SYS_ID_AA64MMFR1_EL1);
233 	GUEST_REG_SYNC(SYS_ID_AA64MMFR2_EL1);
234 	GUEST_REG_SYNC(SYS_ID_AA64ZFR0_EL1);
235 	GUEST_REG_SYNC(SYS_CTR_EL0);
236 	GUEST_REG_SYNC(SYS_MIDR_EL1);
237 	GUEST_REG_SYNC(SYS_REVIDR_EL1);
238 	GUEST_REG_SYNC(SYS_AIDR_EL1);
239 
240 	GUEST_DONE();
241 }
242 
243 /* Return a safe value to a given ftr_bits an ftr value */
get_safe_value(const struct reg_ftr_bits * ftr_bits,uint64_t ftr)244 uint64_t get_safe_value(const struct reg_ftr_bits *ftr_bits, uint64_t ftr)
245 {
246 	uint64_t ftr_max = GENMASK_ULL(ARM64_FEATURE_FIELD_BITS - 1, 0);
247 
248 	if (ftr_bits->sign == FTR_UNSIGNED) {
249 		switch (ftr_bits->type) {
250 		case FTR_EXACT:
251 			ftr = ftr_bits->safe_val;
252 			break;
253 		case FTR_LOWER_SAFE:
254 			if (ftr > ftr_bits->safe_val)
255 				ftr--;
256 			break;
257 		case FTR_HIGHER_SAFE:
258 			if (ftr < ftr_max)
259 				ftr++;
260 			break;
261 		case FTR_HIGHER_OR_ZERO_SAFE:
262 			if (ftr == ftr_max)
263 				ftr = 0;
264 			else if (ftr != 0)
265 				ftr++;
266 			break;
267 		default:
268 			break;
269 		}
270 	} else if (ftr != ftr_max) {
271 		switch (ftr_bits->type) {
272 		case FTR_EXACT:
273 			ftr = ftr_bits->safe_val;
274 			break;
275 		case FTR_LOWER_SAFE:
276 			if (ftr > ftr_bits->safe_val)
277 				ftr--;
278 			break;
279 		case FTR_HIGHER_SAFE:
280 			if (ftr < ftr_max - 1)
281 				ftr++;
282 			break;
283 		case FTR_HIGHER_OR_ZERO_SAFE:
284 			if (ftr != 0 && ftr != ftr_max - 1)
285 				ftr++;
286 			break;
287 		default:
288 			break;
289 		}
290 	}
291 
292 	return ftr;
293 }
294 
295 /* Return an invalid value to a given ftr_bits an ftr value */
get_invalid_value(const struct reg_ftr_bits * ftr_bits,uint64_t ftr)296 uint64_t get_invalid_value(const struct reg_ftr_bits *ftr_bits, uint64_t ftr)
297 {
298 	uint64_t ftr_max = GENMASK_ULL(ARM64_FEATURE_FIELD_BITS - 1, 0);
299 
300 	if (ftr_bits->sign == FTR_UNSIGNED) {
301 		switch (ftr_bits->type) {
302 		case FTR_EXACT:
303 			ftr = max((uint64_t)ftr_bits->safe_val + 1, ftr + 1);
304 			break;
305 		case FTR_LOWER_SAFE:
306 			ftr++;
307 			break;
308 		case FTR_HIGHER_SAFE:
309 			ftr--;
310 			break;
311 		case FTR_HIGHER_OR_ZERO_SAFE:
312 			if (ftr == 0)
313 				ftr = ftr_max;
314 			else
315 				ftr--;
316 			break;
317 		default:
318 			break;
319 		}
320 	} else if (ftr != ftr_max) {
321 		switch (ftr_bits->type) {
322 		case FTR_EXACT:
323 			ftr = max((uint64_t)ftr_bits->safe_val + 1, ftr + 1);
324 			break;
325 		case FTR_LOWER_SAFE:
326 			ftr++;
327 			break;
328 		case FTR_HIGHER_SAFE:
329 			ftr--;
330 			break;
331 		case FTR_HIGHER_OR_ZERO_SAFE:
332 			if (ftr == 0)
333 				ftr = ftr_max - 1;
334 			else
335 				ftr--;
336 			break;
337 		default:
338 			break;
339 		}
340 	} else {
341 		ftr = 0;
342 	}
343 
344 	return ftr;
345 }
346 
test_reg_set_success(struct kvm_vcpu * vcpu,uint64_t reg,const struct reg_ftr_bits * ftr_bits)347 static uint64_t test_reg_set_success(struct kvm_vcpu *vcpu, uint64_t reg,
348 				     const struct reg_ftr_bits *ftr_bits)
349 {
350 	uint8_t shift = ftr_bits->shift;
351 	uint64_t mask = ftr_bits->mask;
352 	uint64_t val, new_val, ftr;
353 
354 	val = vcpu_get_reg(vcpu, reg);
355 	ftr = (val & mask) >> shift;
356 
357 	ftr = get_safe_value(ftr_bits, ftr);
358 
359 	ftr <<= shift;
360 	val &= ~mask;
361 	val |= ftr;
362 
363 	vcpu_set_reg(vcpu, reg, val);
364 	new_val = vcpu_get_reg(vcpu, reg);
365 	TEST_ASSERT_EQ(new_val, val);
366 
367 	return new_val;
368 }
369 
test_reg_set_fail(struct kvm_vcpu * vcpu,uint64_t reg,const struct reg_ftr_bits * ftr_bits)370 static void test_reg_set_fail(struct kvm_vcpu *vcpu, uint64_t reg,
371 			      const struct reg_ftr_bits *ftr_bits)
372 {
373 	uint8_t shift = ftr_bits->shift;
374 	uint64_t mask = ftr_bits->mask;
375 	uint64_t val, old_val, ftr;
376 	int r;
377 
378 	val = vcpu_get_reg(vcpu, reg);
379 	ftr = (val & mask) >> shift;
380 
381 	ftr = get_invalid_value(ftr_bits, ftr);
382 
383 	old_val = val;
384 	ftr <<= shift;
385 	val &= ~mask;
386 	val |= ftr;
387 
388 	r = __vcpu_set_reg(vcpu, reg, val);
389 	TEST_ASSERT(r < 0 && errno == EINVAL,
390 		    "Unexpected KVM_SET_ONE_REG error: r=%d, errno=%d", r, errno);
391 
392 	val = vcpu_get_reg(vcpu, reg);
393 	TEST_ASSERT_EQ(val, old_val);
394 }
395 
396 static uint64_t test_reg_vals[KVM_ARM_FEATURE_ID_RANGE_SIZE];
397 
398 #define encoding_to_range_idx(encoding)							\
399 	KVM_ARM_FEATURE_ID_RANGE_IDX(sys_reg_Op0(encoding), sys_reg_Op1(encoding),	\
400 				     sys_reg_CRn(encoding), sys_reg_CRm(encoding),	\
401 				     sys_reg_Op2(encoding))
402 
403 
test_vm_ftr_id_regs(struct kvm_vcpu * vcpu,bool aarch64_only)404 static void test_vm_ftr_id_regs(struct kvm_vcpu *vcpu, bool aarch64_only)
405 {
406 	uint64_t masks[KVM_ARM_FEATURE_ID_RANGE_SIZE];
407 	struct reg_mask_range range = {
408 		.addr = (__u64)masks,
409 	};
410 	int ret;
411 
412 	/* KVM should return error when reserved field is not zero */
413 	range.reserved[0] = 1;
414 	ret = __vm_ioctl(vcpu->vm, KVM_ARM_GET_REG_WRITABLE_MASKS, &range);
415 	TEST_ASSERT(ret, "KVM doesn't check invalid parameters.");
416 
417 	/* Get writable masks for feature ID registers */
418 	memset(range.reserved, 0, sizeof(range.reserved));
419 	vm_ioctl(vcpu->vm, KVM_ARM_GET_REG_WRITABLE_MASKS, &range);
420 
421 	for (int i = 0; i < ARRAY_SIZE(test_regs); i++) {
422 		const struct reg_ftr_bits *ftr_bits = test_regs[i].ftr_bits;
423 		uint32_t reg_id = test_regs[i].reg;
424 		uint64_t reg = KVM_ARM64_SYS_REG(reg_id);
425 		int idx;
426 
427 		/* Get the index to masks array for the idreg */
428 		idx = encoding_to_range_idx(reg_id);
429 
430 		for (int j = 0;  ftr_bits[j].type != FTR_END; j++) {
431 			/* Skip aarch32 reg on aarch64 only system, since they are RAZ/WI. */
432 			if (aarch64_only && sys_reg_CRm(reg_id) < 4) {
433 				ksft_test_result_skip("%s on AARCH64 only system\n",
434 						      ftr_bits[j].name);
435 				continue;
436 			}
437 
438 			/* Make sure the feature field is writable */
439 			TEST_ASSERT_EQ(masks[idx] & ftr_bits[j].mask, ftr_bits[j].mask);
440 
441 			test_reg_set_fail(vcpu, reg, &ftr_bits[j]);
442 
443 			test_reg_vals[idx] = test_reg_set_success(vcpu, reg,
444 								  &ftr_bits[j]);
445 
446 			ksft_test_result_pass("%s\n", ftr_bits[j].name);
447 		}
448 	}
449 }
450 
451 #define MPAM_IDREG_TEST	6
test_user_set_mpam_reg(struct kvm_vcpu * vcpu)452 static void test_user_set_mpam_reg(struct kvm_vcpu *vcpu)
453 {
454 	uint64_t masks[KVM_ARM_FEATURE_ID_RANGE_SIZE];
455 	struct reg_mask_range range = {
456 		.addr = (__u64)masks,
457 	};
458 	uint64_t val;
459 	int idx, err;
460 
461 	/*
462 	 * If ID_AA64PFR0.MPAM is _not_ officially modifiable and is zero,
463 	 * check that if it can be set to 1, (i.e. it is supported by the
464 	 * hardware), that it can't be set to other values.
465 	 */
466 
467 	/* Get writable masks for feature ID registers */
468 	memset(range.reserved, 0, sizeof(range.reserved));
469 	vm_ioctl(vcpu->vm, KVM_ARM_GET_REG_WRITABLE_MASKS, &range);
470 
471 	/* Writeable? Nothing to test! */
472 	idx = encoding_to_range_idx(SYS_ID_AA64PFR0_EL1);
473 	if ((masks[idx] & ID_AA64PFR0_EL1_MPAM_MASK) == ID_AA64PFR0_EL1_MPAM_MASK) {
474 		ksft_test_result_skip("ID_AA64PFR0_EL1.MPAM is officially writable, nothing to test\n");
475 		return;
476 	}
477 
478 	/* Get the id register value */
479 	val = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR0_EL1));
480 
481 	/* Try to set MPAM=0. This should always be possible. */
482 	val &= ~ID_AA64PFR0_EL1_MPAM_MASK;
483 	val |= FIELD_PREP(ID_AA64PFR0_EL1_MPAM_MASK, 0);
484 	err = __vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR0_EL1), val);
485 	if (err)
486 		ksft_test_result_fail("ID_AA64PFR0_EL1.MPAM=0 was not accepted\n");
487 	else
488 		ksft_test_result_pass("ID_AA64PFR0_EL1.MPAM=0 worked\n");
489 
490 	/* Try to set MPAM=1 */
491 	val &= ~ID_AA64PFR0_EL1_MPAM_MASK;
492 	val |= FIELD_PREP(ID_AA64PFR0_EL1_MPAM_MASK, 1);
493 	err = __vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR0_EL1), val);
494 	if (err)
495 		ksft_test_result_skip("ID_AA64PFR0_EL1.MPAM is not writable, nothing to test\n");
496 	else
497 		ksft_test_result_pass("ID_AA64PFR0_EL1.MPAM=1 was writable\n");
498 
499 	/* Try to set MPAM=2 */
500 	val &= ~ID_AA64PFR0_EL1_MPAM_MASK;
501 	val |= FIELD_PREP(ID_AA64PFR0_EL1_MPAM_MASK, 2);
502 	err = __vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR0_EL1), val);
503 	if (err)
504 		ksft_test_result_pass("ID_AA64PFR0_EL1.MPAM not arbitrarily modifiable\n");
505 	else
506 		ksft_test_result_fail("ID_AA64PFR0_EL1.MPAM value should not be ignored\n");
507 
508 	/* And again for ID_AA64PFR1_EL1.MPAM_frac */
509 	idx = encoding_to_range_idx(SYS_ID_AA64PFR1_EL1);
510 	if ((masks[idx] & ID_AA64PFR1_EL1_MPAM_frac_MASK) == ID_AA64PFR1_EL1_MPAM_frac_MASK) {
511 		ksft_test_result_skip("ID_AA64PFR1_EL1.MPAM_frac is officially writable, nothing to test\n");
512 		return;
513 	}
514 
515 	/* Get the id register value */
516 	val = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR1_EL1));
517 
518 	/* Try to set MPAM_frac=0. This should always be possible. */
519 	val &= ~ID_AA64PFR1_EL1_MPAM_frac_MASK;
520 	val |= FIELD_PREP(ID_AA64PFR1_EL1_MPAM_frac_MASK, 0);
521 	err = __vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR1_EL1), val);
522 	if (err)
523 		ksft_test_result_fail("ID_AA64PFR0_EL1.MPAM_frac=0 was not accepted\n");
524 	else
525 		ksft_test_result_pass("ID_AA64PFR0_EL1.MPAM_frac=0 worked\n");
526 
527 	/* Try to set MPAM_frac=1 */
528 	val &= ~ID_AA64PFR1_EL1_MPAM_frac_MASK;
529 	val |= FIELD_PREP(ID_AA64PFR1_EL1_MPAM_frac_MASK, 1);
530 	err = __vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR1_EL1), val);
531 	if (err)
532 		ksft_test_result_skip("ID_AA64PFR1_EL1.MPAM_frac is not writable, nothing to test\n");
533 	else
534 		ksft_test_result_pass("ID_AA64PFR0_EL1.MPAM_frac=1 was writable\n");
535 
536 	/* Try to set MPAM_frac=2 */
537 	val &= ~ID_AA64PFR1_EL1_MPAM_frac_MASK;
538 	val |= FIELD_PREP(ID_AA64PFR1_EL1_MPAM_frac_MASK, 2);
539 	err = __vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR1_EL1), val);
540 	if (err)
541 		ksft_test_result_pass("ID_AA64PFR1_EL1.MPAM_frac not arbitrarily modifiable\n");
542 	else
543 		ksft_test_result_fail("ID_AA64PFR1_EL1.MPAM_frac value should not be ignored\n");
544 }
545 
test_guest_reg_read(struct kvm_vcpu * vcpu)546 static void test_guest_reg_read(struct kvm_vcpu *vcpu)
547 {
548 	bool done = false;
549 	struct ucall uc;
550 
551 	while (!done) {
552 		vcpu_run(vcpu);
553 
554 		switch (get_ucall(vcpu, &uc)) {
555 		case UCALL_ABORT:
556 			REPORT_GUEST_ASSERT(uc);
557 			break;
558 		case UCALL_SYNC:
559 			/* Make sure the written values are seen by guest */
560 			TEST_ASSERT_EQ(test_reg_vals[encoding_to_range_idx(uc.args[2])],
561 				       uc.args[3]);
562 			break;
563 		case UCALL_DONE:
564 			done = true;
565 			break;
566 		default:
567 			TEST_FAIL("Unexpected ucall: %lu", uc.cmd);
568 		}
569 	}
570 }
571 
572 /* Politely lifted from arch/arm64/include/asm/cache.h */
573 /* Ctypen, bits[3(n - 1) + 2 : 3(n - 1)], for n = 1 to 7 */
574 #define CLIDR_CTYPE_SHIFT(level)	(3 * (level - 1))
575 #define CLIDR_CTYPE_MASK(level)		(7 << CLIDR_CTYPE_SHIFT(level))
576 #define CLIDR_CTYPE(clidr, level)	\
577 	(((clidr) & CLIDR_CTYPE_MASK(level)) >> CLIDR_CTYPE_SHIFT(level))
578 
test_clidr(struct kvm_vcpu * vcpu)579 static void test_clidr(struct kvm_vcpu *vcpu)
580 {
581 	uint64_t clidr;
582 	int level;
583 
584 	clidr = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_CLIDR_EL1));
585 
586 	/* find the first empty level in the cache hierarchy */
587 	for (level = 1; level < 7; level++) {
588 		if (!CLIDR_CTYPE(clidr, level))
589 			break;
590 	}
591 
592 	/*
593 	 * If you have a mind-boggling 7 levels of cache, congratulations, you
594 	 * get to fix this.
595 	 */
596 	TEST_ASSERT(level <= 7, "can't find an empty level in cache hierarchy");
597 
598 	/* stick in a unified cache level */
599 	clidr |= BIT(2) << CLIDR_CTYPE_SHIFT(level);
600 
601 	vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_CLIDR_EL1), clidr);
602 	test_reg_vals[encoding_to_range_idx(SYS_CLIDR_EL1)] = clidr;
603 }
604 
test_ctr(struct kvm_vcpu * vcpu)605 static void test_ctr(struct kvm_vcpu *vcpu)
606 {
607 	u64 ctr;
608 
609 	ctr = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_CTR_EL0));
610 	ctr &= ~CTR_EL0_DIC_MASK;
611 	if (ctr & CTR_EL0_IminLine_MASK)
612 		ctr--;
613 
614 	vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_CTR_EL0), ctr);
615 	test_reg_vals[encoding_to_range_idx(SYS_CTR_EL0)] = ctr;
616 }
617 
test_id_reg(struct kvm_vcpu * vcpu,u32 id)618 static void test_id_reg(struct kvm_vcpu *vcpu, u32 id)
619 {
620 	u64 val;
621 
622 	val = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(id));
623 	val++;
624 	vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(id), val);
625 	test_reg_vals[encoding_to_range_idx(id)] = val;
626 }
627 
test_vcpu_ftr_id_regs(struct kvm_vcpu * vcpu)628 static void test_vcpu_ftr_id_regs(struct kvm_vcpu *vcpu)
629 {
630 	test_clidr(vcpu);
631 	test_ctr(vcpu);
632 
633 	test_id_reg(vcpu, SYS_MPIDR_EL1);
634 	ksft_test_result_pass("%s\n", __func__);
635 }
636 
test_vcpu_non_ftr_id_regs(struct kvm_vcpu * vcpu)637 static void test_vcpu_non_ftr_id_regs(struct kvm_vcpu *vcpu)
638 {
639 	test_id_reg(vcpu, SYS_MIDR_EL1);
640 	test_id_reg(vcpu, SYS_REVIDR_EL1);
641 	test_id_reg(vcpu, SYS_AIDR_EL1);
642 
643 	ksft_test_result_pass("%s\n", __func__);
644 }
645 
test_assert_id_reg_unchanged(struct kvm_vcpu * vcpu,uint32_t encoding)646 static void test_assert_id_reg_unchanged(struct kvm_vcpu *vcpu, uint32_t encoding)
647 {
648 	size_t idx = encoding_to_range_idx(encoding);
649 	uint64_t observed;
650 
651 	observed = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(encoding));
652 	TEST_ASSERT_EQ(test_reg_vals[idx], observed);
653 }
654 
test_reset_preserves_id_regs(struct kvm_vcpu * vcpu)655 static void test_reset_preserves_id_regs(struct kvm_vcpu *vcpu)
656 {
657 	/*
658 	 * Calls KVM_ARM_VCPU_INIT behind the scenes, which will do an
659 	 * architectural reset of the vCPU.
660 	 */
661 	aarch64_vcpu_setup(vcpu, NULL);
662 
663 	for (int i = 0; i < ARRAY_SIZE(test_regs); i++)
664 		test_assert_id_reg_unchanged(vcpu, test_regs[i].reg);
665 
666 	test_assert_id_reg_unchanged(vcpu, SYS_MPIDR_EL1);
667 	test_assert_id_reg_unchanged(vcpu, SYS_CLIDR_EL1);
668 	test_assert_id_reg_unchanged(vcpu, SYS_CTR_EL0);
669 	test_assert_id_reg_unchanged(vcpu, SYS_MIDR_EL1);
670 	test_assert_id_reg_unchanged(vcpu, SYS_REVIDR_EL1);
671 	test_assert_id_reg_unchanged(vcpu, SYS_AIDR_EL1);
672 
673 	ksft_test_result_pass("%s\n", __func__);
674 }
675 
main(void)676 int main(void)
677 {
678 	struct kvm_vcpu *vcpu;
679 	struct kvm_vm *vm;
680 	bool aarch64_only;
681 	uint64_t val, el0;
682 	int test_cnt;
683 
684 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_ARM_SUPPORTED_REG_MASK_RANGES));
685 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_ARM_WRITABLE_IMP_ID_REGS));
686 
687 	vm = vm_create(1);
688 	vm_enable_cap(vm, KVM_CAP_ARM_WRITABLE_IMP_ID_REGS, 0);
689 	vcpu = vm_vcpu_add(vm, 0, guest_code);
690 
691 	/* Check for AARCH64 only system */
692 	val = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR0_EL1));
693 	el0 = FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_EL0), val);
694 	aarch64_only = (el0 == ID_AA64PFR0_EL1_EL0_IMP);
695 
696 	ksft_print_header();
697 
698 	test_cnt = ARRAY_SIZE(ftr_id_aa64dfr0_el1) + ARRAY_SIZE(ftr_id_dfr0_el1) +
699 		   ARRAY_SIZE(ftr_id_aa64isar0_el1) + ARRAY_SIZE(ftr_id_aa64isar1_el1) +
700 		   ARRAY_SIZE(ftr_id_aa64isar2_el1) + ARRAY_SIZE(ftr_id_aa64pfr0_el1) +
701 		   ARRAY_SIZE(ftr_id_aa64pfr1_el1) + ARRAY_SIZE(ftr_id_aa64mmfr0_el1) +
702 		   ARRAY_SIZE(ftr_id_aa64mmfr1_el1) + ARRAY_SIZE(ftr_id_aa64mmfr2_el1) +
703 		   ARRAY_SIZE(ftr_id_aa64zfr0_el1) - ARRAY_SIZE(test_regs) + 3 +
704 		   MPAM_IDREG_TEST;
705 
706 	ksft_set_plan(test_cnt);
707 
708 	test_vm_ftr_id_regs(vcpu, aarch64_only);
709 	test_vcpu_ftr_id_regs(vcpu);
710 	test_vcpu_non_ftr_id_regs(vcpu);
711 	test_user_set_mpam_reg(vcpu);
712 
713 	test_guest_reg_read(vcpu);
714 
715 	test_reset_preserves_id_regs(vcpu);
716 
717 	kvm_vm_free(vm);
718 
719 	ksft_finished();
720 }
721