1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * amx tests 4 * 5 * Copyright (C) 2021, Intel, Inc. 6 * 7 * Tests for amx #NM exception and save/restore. 8 */ 9 10 #define _GNU_SOURCE /* for program_invocation_short_name */ 11 #include <fcntl.h> 12 #include <stdio.h> 13 #include <stdlib.h> 14 #include <string.h> 15 #include <sys/ioctl.h> 16 #include <sys/syscall.h> 17 18 #include "test_util.h" 19 20 #include "kvm_util.h" 21 #include "processor.h" 22 #include "vmx.h" 23 24 #ifndef __x86_64__ 25 # error This test is 64-bit only 26 #endif 27 28 #define NUM_TILES 8 29 #define TILE_SIZE 1024 30 #define XSAVE_SIZE ((NUM_TILES * TILE_SIZE) + PAGE_SIZE) 31 32 /* Tile configuration associated: */ 33 #define PALETTE_TABLE_INDEX 1 34 #define MAX_TILES 16 35 #define RESERVED_BYTES 14 36 37 #define XSAVE_HDR_OFFSET 512 38 39 struct tile_config { 40 u8 palette_id; 41 u8 start_row; 42 u8 reserved[RESERVED_BYTES]; 43 u16 colsb[MAX_TILES]; 44 u8 rows[MAX_TILES]; 45 }; 46 47 struct tile_data { 48 u8 data[NUM_TILES * TILE_SIZE]; 49 }; 50 51 struct xtile_info { 52 u16 bytes_per_tile; 53 u16 bytes_per_row; 54 u16 max_names; 55 u16 max_rows; 56 u32 xsave_offset; 57 u32 xsave_size; 58 }; 59 60 static struct xtile_info xtile; 61 62 static inline void __ldtilecfg(void *cfg) 63 { 64 asm volatile(".byte 0xc4,0xe2,0x78,0x49,0x00" 65 : : "a"(cfg)); 66 } 67 68 static inline void __tileloadd(void *tile) 69 { 70 asm volatile(".byte 0xc4,0xe2,0x7b,0x4b,0x04,0x10" 71 : : "a"(tile), "d"(0)); 72 } 73 74 static inline void __tilerelease(void) 75 { 76 asm volatile(".byte 0xc4, 0xe2, 0x78, 0x49, 0xc0" ::); 77 } 78 79 static inline void __xsavec(struct xstate *xstate, uint64_t rfbm) 80 { 81 uint32_t rfbm_lo = rfbm; 82 uint32_t rfbm_hi = rfbm >> 32; 83 84 asm volatile("xsavec (%%rdi)" 85 : : "D" (xstate), "a" (rfbm_lo), "d" (rfbm_hi) 86 : "memory"); 87 } 88 89 static void check_xtile_info(void) 90 { 91 GUEST_ASSERT(this_cpu_has_p(X86_PROPERTY_XSTATE_MAX_SIZE_XCR0)); 92 GUEST_ASSERT(this_cpu_property(X86_PROPERTY_XSTATE_MAX_SIZE_XCR0) <= XSAVE_SIZE); 93 94 xtile.xsave_offset = this_cpu_property(X86_PROPERTY_XSTATE_TILE_OFFSET); 95 GUEST_ASSERT(xtile.xsave_offset == 2816); 96 xtile.xsave_size = this_cpu_property(X86_PROPERTY_XSTATE_TILE_SIZE); 97 GUEST_ASSERT(xtile.xsave_size == 8192); 98 GUEST_ASSERT(sizeof(struct tile_data) >= xtile.xsave_size); 99 100 GUEST_ASSERT(this_cpu_has_p(X86_PROPERTY_AMX_MAX_PALETTE_TABLES)); 101 GUEST_ASSERT(this_cpu_property(X86_PROPERTY_AMX_MAX_PALETTE_TABLES) >= 102 PALETTE_TABLE_INDEX); 103 104 GUEST_ASSERT(this_cpu_has_p(X86_PROPERTY_AMX_NR_TILE_REGS)); 105 xtile.max_names = this_cpu_property(X86_PROPERTY_AMX_NR_TILE_REGS); 106 GUEST_ASSERT(xtile.max_names == 8); 107 xtile.bytes_per_tile = this_cpu_property(X86_PROPERTY_AMX_BYTES_PER_TILE); 108 GUEST_ASSERT(xtile.bytes_per_tile == 1024); 109 xtile.bytes_per_row = this_cpu_property(X86_PROPERTY_AMX_BYTES_PER_ROW); 110 GUEST_ASSERT(xtile.bytes_per_row == 64); 111 xtile.max_rows = this_cpu_property(X86_PROPERTY_AMX_MAX_ROWS); 112 GUEST_ASSERT(xtile.max_rows == 16); 113 } 114 115 static void set_tilecfg(struct tile_config *cfg) 116 { 117 int i; 118 119 /* Only palette id 1 */ 120 cfg->palette_id = 1; 121 for (i = 0; i < xtile.max_names; i++) { 122 cfg->colsb[i] = xtile.bytes_per_row; 123 cfg->rows[i] = xtile.max_rows; 124 } 125 } 126 127 static void init_regs(void) 128 { 129 uint64_t cr4, xcr0; 130 131 GUEST_ASSERT(this_cpu_has(X86_FEATURE_XSAVE)); 132 133 /* turn on CR4.OSXSAVE */ 134 cr4 = get_cr4(); 135 cr4 |= X86_CR4_OSXSAVE; 136 set_cr4(cr4); 137 GUEST_ASSERT(this_cpu_has(X86_FEATURE_OSXSAVE)); 138 139 xcr0 = xgetbv(0); 140 xcr0 |= XFEATURE_MASK_XTILE; 141 xsetbv(0x0, xcr0); 142 GUEST_ASSERT((xgetbv(0) & XFEATURE_MASK_XTILE) == XFEATURE_MASK_XTILE); 143 } 144 145 static void __attribute__((__flatten__)) guest_code(struct tile_config *amx_cfg, 146 struct tile_data *tiledata, 147 struct xstate *xstate) 148 { 149 init_regs(); 150 check_xtile_info(); 151 GUEST_SYNC(1); 152 153 /* xfd=0, enable amx */ 154 wrmsr(MSR_IA32_XFD, 0); 155 GUEST_SYNC(2); 156 GUEST_ASSERT(rdmsr(MSR_IA32_XFD) == 0); 157 set_tilecfg(amx_cfg); 158 __ldtilecfg(amx_cfg); 159 GUEST_SYNC(3); 160 /* Check save/restore when trap to userspace */ 161 __tileloadd(tiledata); 162 GUEST_SYNC(4); 163 __tilerelease(); 164 GUEST_SYNC(5); 165 /* 166 * After XSAVEC, XTILEDATA is cleared in the xstate_bv but is set in 167 * the xcomp_bv. 168 */ 169 xstate->header.xstate_bv = XFEATURE_MASK_XTILE_DATA; 170 __xsavec(xstate, XFEATURE_MASK_XTILE_DATA); 171 GUEST_ASSERT(!(xstate->header.xstate_bv & XFEATURE_MASK_XTILE_DATA)); 172 GUEST_ASSERT(xstate->header.xcomp_bv & XFEATURE_MASK_XTILE_DATA); 173 174 /* xfd=0x40000, disable amx tiledata */ 175 wrmsr(MSR_IA32_XFD, XFEATURE_MASK_XTILE_DATA); 176 177 /* 178 * XTILEDATA is cleared in xstate_bv but set in xcomp_bv, this property 179 * remains the same even when amx tiledata is disabled by IA32_XFD. 180 */ 181 xstate->header.xstate_bv = XFEATURE_MASK_XTILE_DATA; 182 __xsavec(xstate, XFEATURE_MASK_XTILE_DATA); 183 GUEST_ASSERT(!(xstate->header.xstate_bv & XFEATURE_MASK_XTILE_DATA)); 184 GUEST_ASSERT((xstate->header.xcomp_bv & XFEATURE_MASK_XTILE_DATA)); 185 186 GUEST_SYNC(6); 187 GUEST_ASSERT(rdmsr(MSR_IA32_XFD) == XFEATURE_MASK_XTILE_DATA); 188 set_tilecfg(amx_cfg); 189 __ldtilecfg(amx_cfg); 190 /* Trigger #NM exception */ 191 __tileloadd(tiledata); 192 GUEST_SYNC(10); 193 194 GUEST_DONE(); 195 } 196 197 void guest_nm_handler(struct ex_regs *regs) 198 { 199 /* Check if #NM is triggered by XFEATURE_MASK_XTILE_DATA */ 200 GUEST_SYNC(7); 201 GUEST_ASSERT(!(get_cr0() & X86_CR0_TS)); 202 GUEST_ASSERT(rdmsr(MSR_IA32_XFD_ERR) == XFEATURE_MASK_XTILE_DATA); 203 GUEST_ASSERT(rdmsr(MSR_IA32_XFD) == XFEATURE_MASK_XTILE_DATA); 204 GUEST_SYNC(8); 205 GUEST_ASSERT(rdmsr(MSR_IA32_XFD_ERR) == XFEATURE_MASK_XTILE_DATA); 206 GUEST_ASSERT(rdmsr(MSR_IA32_XFD) == XFEATURE_MASK_XTILE_DATA); 207 /* Clear xfd_err */ 208 wrmsr(MSR_IA32_XFD_ERR, 0); 209 /* xfd=0, enable amx */ 210 wrmsr(MSR_IA32_XFD, 0); 211 GUEST_SYNC(9); 212 } 213 214 int main(int argc, char *argv[]) 215 { 216 struct kvm_regs regs1, regs2; 217 struct kvm_vcpu *vcpu; 218 struct kvm_vm *vm; 219 struct kvm_x86_state *state; 220 int xsave_restore_size; 221 vm_vaddr_t amx_cfg, tiledata, xstate; 222 struct ucall uc; 223 u32 amx_offset; 224 int ret; 225 226 /* 227 * Note, all off-by-default features must be enabled before anything 228 * caches KVM_GET_SUPPORTED_CPUID, e.g. before using kvm_cpu_has(). 229 */ 230 vm_xsave_require_permission(XFEATURE_MASK_XTILE_DATA); 231 232 TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_XFD)); 233 TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_XSAVE)); 234 TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_AMX_TILE)); 235 TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_XTILECFG)); 236 TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_XTILEDATA)); 237 TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_XTILEDATA_XFD)); 238 239 /* Create VM */ 240 vm = vm_create_with_one_vcpu(&vcpu, guest_code); 241 242 TEST_ASSERT(kvm_cpu_has_p(X86_PROPERTY_XSTATE_MAX_SIZE), 243 "KVM should enumerate max XSAVE size when XSAVE is supported"); 244 xsave_restore_size = kvm_cpu_property(X86_PROPERTY_XSTATE_MAX_SIZE); 245 246 vcpu_regs_get(vcpu, ®s1); 247 248 /* Register #NM handler */ 249 vm_init_descriptor_tables(vm); 250 vcpu_init_descriptor_tables(vcpu); 251 vm_install_exception_handler(vm, NM_VECTOR, guest_nm_handler); 252 253 /* amx cfg for guest_code */ 254 amx_cfg = vm_vaddr_alloc_page(vm); 255 memset(addr_gva2hva(vm, amx_cfg), 0x0, getpagesize()); 256 257 /* amx tiledata for guest_code */ 258 tiledata = vm_vaddr_alloc_pages(vm, 2); 259 memset(addr_gva2hva(vm, tiledata), rand() | 1, 2 * getpagesize()); 260 261 /* XSAVE state for guest_code */ 262 xstate = vm_vaddr_alloc_pages(vm, DIV_ROUND_UP(XSAVE_SIZE, PAGE_SIZE)); 263 memset(addr_gva2hva(vm, xstate), 0, PAGE_SIZE * DIV_ROUND_UP(XSAVE_SIZE, PAGE_SIZE)); 264 vcpu_args_set(vcpu, 3, amx_cfg, tiledata, xstate); 265 266 for (;;) { 267 vcpu_run(vcpu); 268 TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_IO); 269 270 switch (get_ucall(vcpu, &uc)) { 271 case UCALL_ABORT: 272 REPORT_GUEST_ASSERT(uc); 273 /* NOT REACHED */ 274 case UCALL_SYNC: 275 switch (uc.args[1]) { 276 case 1: 277 case 2: 278 case 3: 279 case 5: 280 case 6: 281 case 7: 282 case 8: 283 fprintf(stderr, "GUEST_SYNC(%ld)\n", uc.args[1]); 284 break; 285 case 4: 286 case 10: 287 fprintf(stderr, 288 "GUEST_SYNC(%ld), check save/restore status\n", uc.args[1]); 289 290 /* Compacted mode, get amx offset by xsave area 291 * size subtract 8K amx size. 292 */ 293 amx_offset = xsave_restore_size - NUM_TILES*TILE_SIZE; 294 state = vcpu_save_state(vcpu); 295 void *amx_start = (void *)state->xsave + amx_offset; 296 void *tiles_data = (void *)addr_gva2hva(vm, tiledata); 297 /* Only check TMM0 register, 1 tile */ 298 ret = memcmp(amx_start, tiles_data, TILE_SIZE); 299 TEST_ASSERT(ret == 0, "memcmp failed, ret=%d", ret); 300 kvm_x86_state_cleanup(state); 301 break; 302 case 9: 303 fprintf(stderr, 304 "GUEST_SYNC(%ld), #NM exception and enable amx\n", uc.args[1]); 305 break; 306 } 307 break; 308 case UCALL_DONE: 309 fprintf(stderr, "UCALL_DONE\n"); 310 goto done; 311 default: 312 TEST_FAIL("Unknown ucall %lu", uc.cmd); 313 } 314 315 state = vcpu_save_state(vcpu); 316 memset(®s1, 0, sizeof(regs1)); 317 vcpu_regs_get(vcpu, ®s1); 318 319 kvm_vm_release(vm); 320 321 /* Restore state in a new VM. */ 322 vcpu = vm_recreate_with_one_vcpu(vm); 323 vcpu_load_state(vcpu, state); 324 kvm_x86_state_cleanup(state); 325 326 memset(®s2, 0, sizeof(regs2)); 327 vcpu_regs_get(vcpu, ®s2); 328 TEST_ASSERT(!memcmp(®s1, ®s2, sizeof(regs2)), 329 "Unexpected register values after vcpu_load_state; rdi: %lx rsi: %lx", 330 (ulong) regs2.rdi, (ulong) regs2.rsi); 331 } 332 done: 333 kvm_vm_free(vm); 334 } 335