1// SPDX-License-Identifier: GPL-2.0-or-later 2/* 3 * Copyright (C) 2001 Ben. Herrenschmidt (benh@kernel.crashing.org) 4 * 5 * Modifications for ppc64: 6 * Copyright (C) 2003 Dave Engebretsen <engebret@us.ibm.com> 7 * 8 * Copyright 2008 Michael Ellerman, IBM Corporation. 9 */ 10 11#include <linux/types.h> 12#include <linux/jump_label.h> 13#include <linux/kernel.h> 14#include <linux/string.h> 15#include <linux/init.h> 16#include <linux/sched/mm.h> 17#include <linux/stop_machine.h> 18#include <asm/cputable.h> 19#include <asm/code-patching.h> 20#include <asm/interrupt.h> 21#include <asm/page.h> 22#include <asm/sections.h> 23#include <asm/setup.h> 24#include <asm/security_features.h> 25#include <asm/firmware.h> 26#include <asm/inst.h> 27 28struct fixup_entry { 29 unsigned long mask; 30 unsigned long value; 31 long start_off; 32 long end_off; 33 long alt_start_off; 34 long alt_end_off; 35}; 36 37static u32 *calc_addr(struct fixup_entry *fcur, long offset) 38{ 39 /* 40 * We store the offset to the code as a negative offset from 41 * the start of the alt_entry, to support the VDSO. This 42 * routine converts that back into an actual address. 43 */ 44 return (u32 *)((unsigned long)fcur + offset); 45} 46 47static int patch_alt_instruction(u32 *src, u32 *dest, u32 *alt_start, u32 *alt_end) 48{ 49 int err; 50 ppc_inst_t instr; 51 52 instr = ppc_inst_read(src); 53 54 if (instr_is_relative_branch(ppc_inst_read(src))) { 55 u32 *target = (u32 *)branch_target(src); 56 57 /* Branch within the section doesn't need translating */ 58 if (target < alt_start || target > alt_end) { 59 err = translate_branch(&instr, dest, src); 60 if (err) 61 return 1; 62 } 63 } 64 65 raw_patch_instruction(dest, instr); 66 67 return 0; 68} 69 70static int patch_feature_section_mask(unsigned long value, unsigned long mask, 71 struct fixup_entry *fcur) 72{ 73 u32 *start, *end, *alt_start, *alt_end, *src, *dest; 74 75 start = calc_addr(fcur, fcur->start_off); 76 end = calc_addr(fcur, fcur->end_off); 77 alt_start = calc_addr(fcur, fcur->alt_start_off); 78 alt_end = calc_addr(fcur, fcur->alt_end_off); 79 80 if ((alt_end - alt_start) > (end - start)) 81 return 1; 82 83 if ((value & fcur->mask & mask) == (fcur->value & mask)) 84 return 0; 85 86 src = alt_start; 87 dest = start; 88 89 for (; src < alt_end; src = ppc_inst_next(src, src), 90 dest = ppc_inst_next(dest, dest)) { 91 if (patch_alt_instruction(src, dest, alt_start, alt_end)) 92 return 1; 93 } 94 95 for (; dest < end; dest++) 96 raw_patch_instruction(dest, ppc_inst(PPC_RAW_NOP())); 97 98 return 0; 99} 100 101static void do_feature_fixups_mask(unsigned long value, unsigned long mask, 102 void *fixup_start, void *fixup_end) 103{ 104 struct fixup_entry *fcur, *fend; 105 106 fcur = fixup_start; 107 fend = fixup_end; 108 109 for (; fcur < fend; fcur++) { 110 if (patch_feature_section_mask(value, mask, fcur)) { 111 WARN_ON(1); 112 printk("Unable to patch feature section at %p - %p" \ 113 " with %p - %p\n", 114 calc_addr(fcur, fcur->start_off), 115 calc_addr(fcur, fcur->end_off), 116 calc_addr(fcur, fcur->alt_start_off), 117 calc_addr(fcur, fcur->alt_end_off)); 118 } 119 } 120} 121 122void do_feature_fixups(unsigned long value, void *fixup_start, void *fixup_end) 123{ 124 do_feature_fixups_mask(value, ~0, fixup_start, fixup_end); 125} 126 127#ifdef CONFIG_PPC_BARRIER_NOSPEC 128static bool is_fixup_addr_valid(void *dest, size_t size) 129{ 130 return system_state < SYSTEM_FREEING_INITMEM || 131 !init_section_contains(dest, size); 132} 133 134static int do_patch_fixups(long *start, long *end, unsigned int *instrs, int num) 135{ 136 int i; 137 138 for (i = 0; start < end; start++, i++) { 139 int j; 140 unsigned int *dest = (void *)start + *start; 141 142 if (!is_fixup_addr_valid(dest, sizeof(*instrs) * num)) 143 continue; 144 145 pr_devel("patching dest %lx\n", (unsigned long)dest); 146 147 for (j = 0; j < num; j++) 148 patch_instruction(dest + j, ppc_inst(instrs[j])); 149 } 150 return i; 151} 152#endif 153 154#ifdef CONFIG_PPC_BOOK3S_64 155static int do_patch_entry_fixups(long *start, long *end, unsigned int *instrs, 156 bool do_fallback, void *fallback) 157{ 158 int i; 159 160 for (i = 0; start < end; start++, i++) { 161 unsigned int *dest = (void *)start + *start; 162 163 if (!is_fixup_addr_valid(dest, sizeof(*instrs) * 3)) 164 continue; 165 166 pr_devel("patching dest %lx\n", (unsigned long)dest); 167 168 // See comment in do_entry_flush_fixups() RE order of patching 169 if (do_fallback) { 170 patch_instruction(dest, ppc_inst(instrs[0])); 171 patch_instruction(dest + 2, ppc_inst(instrs[2])); 172 patch_branch(dest + 1, (unsigned long)fallback, BRANCH_SET_LINK); 173 } else { 174 patch_instruction(dest + 1, ppc_inst(instrs[1])); 175 patch_instruction(dest + 2, ppc_inst(instrs[2])); 176 patch_instruction(dest, ppc_inst(instrs[0])); 177 } 178 } 179 return i; 180} 181 182static void do_stf_entry_barrier_fixups(enum stf_barrier_type types) 183{ 184 unsigned int instrs[3]; 185 long *start, *end; 186 int i; 187 188 start = PTRRELOC(&__start___stf_entry_barrier_fixup); 189 end = PTRRELOC(&__stop___stf_entry_barrier_fixup); 190 191 instrs[0] = PPC_RAW_NOP(); 192 instrs[1] = PPC_RAW_NOP(); 193 instrs[2] = PPC_RAW_NOP(); 194 195 i = 0; 196 if (types & STF_BARRIER_FALLBACK) { 197 instrs[i++] = PPC_RAW_MFLR(_R10); 198 instrs[i++] = PPC_RAW_NOP(); /* branch patched below */ 199 instrs[i++] = PPC_RAW_MTLR(_R10); 200 } else if (types & STF_BARRIER_EIEIO) { 201 instrs[i++] = PPC_RAW_EIEIO() | 0x02000000; /* eieio + bit 6 hint */ 202 } else if (types & STF_BARRIER_SYNC_ORI) { 203 instrs[i++] = PPC_RAW_SYNC(); 204 instrs[i++] = PPC_RAW_LD(_R10, _R13, 0); 205 instrs[i++] = PPC_RAW_ORI(_R31, _R31, 0); /* speculation barrier */ 206 } 207 208 i = do_patch_entry_fixups(start, end, instrs, types & STF_BARRIER_FALLBACK, 209 &stf_barrier_fallback); 210 211 printk(KERN_DEBUG "stf-barrier: patched %d entry locations (%s barrier)\n", i, 212 (types == STF_BARRIER_NONE) ? "no" : 213 (types == STF_BARRIER_FALLBACK) ? "fallback" : 214 (types == STF_BARRIER_EIEIO) ? "eieio" : 215 (types == (STF_BARRIER_SYNC_ORI)) ? "hwsync" 216 : "unknown"); 217} 218 219static void do_stf_exit_barrier_fixups(enum stf_barrier_type types) 220{ 221 unsigned int instrs[6]; 222 long *start, *end; 223 int i; 224 225 start = PTRRELOC(&__start___stf_exit_barrier_fixup); 226 end = PTRRELOC(&__stop___stf_exit_barrier_fixup); 227 228 instrs[0] = PPC_RAW_NOP(); 229 instrs[1] = PPC_RAW_NOP(); 230 instrs[2] = PPC_RAW_NOP(); 231 instrs[3] = PPC_RAW_NOP(); 232 instrs[4] = PPC_RAW_NOP(); 233 instrs[5] = PPC_RAW_NOP(); 234 235 i = 0; 236 if (types & STF_BARRIER_FALLBACK || types & STF_BARRIER_SYNC_ORI) { 237 if (cpu_has_feature(CPU_FTR_HVMODE)) { 238 instrs[i++] = PPC_RAW_MTSPR(SPRN_HSPRG1, _R13); 239 instrs[i++] = PPC_RAW_MFSPR(_R13, SPRN_HSPRG0); 240 } else { 241 instrs[i++] = PPC_RAW_MTSPR(SPRN_SPRG2, _R13); 242 instrs[i++] = PPC_RAW_MFSPR(_R13, SPRN_SPRG1); 243 } 244 instrs[i++] = PPC_RAW_SYNC(); 245 instrs[i++] = PPC_RAW_LD(_R13, _R13, 0); 246 instrs[i++] = PPC_RAW_ORI(_R31, _R31, 0); /* speculation barrier */ 247 if (cpu_has_feature(CPU_FTR_HVMODE)) 248 instrs[i++] = PPC_RAW_MFSPR(_R13, SPRN_HSPRG1); 249 else 250 instrs[i++] = PPC_RAW_MFSPR(_R13, SPRN_SPRG2); 251 } else if (types & STF_BARRIER_EIEIO) { 252 instrs[i++] = PPC_RAW_EIEIO() | 0x02000000; /* eieio + bit 6 hint */ 253 } 254 255 i = do_patch_fixups(start, end, instrs, ARRAY_SIZE(instrs)); 256 257 printk(KERN_DEBUG "stf-barrier: patched %d exit locations (%s barrier)\n", i, 258 (types == STF_BARRIER_NONE) ? "no" : 259 (types == STF_BARRIER_FALLBACK) ? "fallback" : 260 (types == STF_BARRIER_EIEIO) ? "eieio" : 261 (types == (STF_BARRIER_SYNC_ORI)) ? "hwsync" 262 : "unknown"); 263} 264 265static bool stf_exit_reentrant = false; 266static bool rfi_exit_reentrant = false; 267static DEFINE_MUTEX(exit_flush_lock); 268 269static int __do_stf_barrier_fixups(void *data) 270{ 271 enum stf_barrier_type *types = data; 272 273 do_stf_entry_barrier_fixups(*types); 274 do_stf_exit_barrier_fixups(*types); 275 276 return 0; 277} 278 279void do_stf_barrier_fixups(enum stf_barrier_type types) 280{ 281 /* 282 * The call to the fallback entry flush, and the fallback/sync-ori exit 283 * flush can not be safely patched in/out while other CPUs are 284 * executing them. So call __do_stf_barrier_fixups() on one CPU while 285 * all other CPUs spin in the stop machine core with interrupts hard 286 * disabled. 287 * 288 * The branch to mark interrupt exits non-reentrant is enabled first, 289 * then stop_machine runs which will ensure all CPUs are out of the 290 * low level interrupt exit code before patching. After the patching, 291 * if allowed, then flip the branch to allow fast exits. 292 */ 293 294 // Prevent static key update races with do_rfi_flush_fixups() 295 mutex_lock(&exit_flush_lock); 296 static_branch_enable(&interrupt_exit_not_reentrant); 297 298 stop_machine(__do_stf_barrier_fixups, &types, NULL); 299 300 if ((types & STF_BARRIER_FALLBACK) || (types & STF_BARRIER_SYNC_ORI)) 301 stf_exit_reentrant = false; 302 else 303 stf_exit_reentrant = true; 304 305 if (stf_exit_reentrant && rfi_exit_reentrant) 306 static_branch_disable(&interrupt_exit_not_reentrant); 307 308 mutex_unlock(&exit_flush_lock); 309} 310 311void do_uaccess_flush_fixups(enum l1d_flush_type types) 312{ 313 unsigned int instrs[4]; 314 long *start, *end; 315 int i; 316 317 start = PTRRELOC(&__start___uaccess_flush_fixup); 318 end = PTRRELOC(&__stop___uaccess_flush_fixup); 319 320 instrs[0] = PPC_RAW_NOP(); 321 instrs[1] = PPC_RAW_NOP(); 322 instrs[2] = PPC_RAW_NOP(); 323 instrs[3] = PPC_RAW_BLR(); 324 325 i = 0; 326 if (types == L1D_FLUSH_FALLBACK) { 327 instrs[3] = PPC_RAW_NOP(); 328 /* fallthrough to fallback flush */ 329 } 330 331 if (types & L1D_FLUSH_ORI) { 332 instrs[i++] = PPC_RAW_ORI(_R31, _R31, 0); /* speculation barrier */ 333 instrs[i++] = PPC_RAW_ORI(_R30, _R30, 0); /* L1d flush */ 334 } 335 336 if (types & L1D_FLUSH_MTTRIG) 337 instrs[i++] = PPC_RAW_MTSPR(SPRN_TRIG2, _R0); 338 339 i = do_patch_fixups(start, end, instrs, ARRAY_SIZE(instrs)); 340 341 printk(KERN_DEBUG "uaccess-flush: patched %d locations (%s flush)\n", i, 342 (types == L1D_FLUSH_NONE) ? "no" : 343 (types == L1D_FLUSH_FALLBACK) ? "fallback displacement" : 344 (types & L1D_FLUSH_ORI) ? (types & L1D_FLUSH_MTTRIG) 345 ? "ori+mttrig type" 346 : "ori type" : 347 (types & L1D_FLUSH_MTTRIG) ? "mttrig type" 348 : "unknown"); 349} 350 351static int __do_entry_flush_fixups(void *data) 352{ 353 enum l1d_flush_type types = *(enum l1d_flush_type *)data; 354 unsigned int instrs[3]; 355 long *start, *end; 356 int i; 357 358 instrs[0] = PPC_RAW_NOP(); 359 instrs[1] = PPC_RAW_NOP(); 360 instrs[2] = PPC_RAW_NOP(); 361 362 i = 0; 363 if (types == L1D_FLUSH_FALLBACK) { 364 instrs[i++] = PPC_RAW_MFLR(_R10); 365 instrs[i++] = PPC_RAW_NOP(); /* branch patched below */ 366 instrs[i++] = PPC_RAW_MTLR(_R10); 367 } 368 369 if (types & L1D_FLUSH_ORI) { 370 instrs[i++] = PPC_RAW_ORI(_R31, _R31, 0); /* speculation barrier */ 371 instrs[i++] = PPC_RAW_ORI(_R30, _R30, 0); /* L1d flush */ 372 } 373 374 if (types & L1D_FLUSH_MTTRIG) 375 instrs[i++] = PPC_RAW_MTSPR(SPRN_TRIG2, _R0); 376 377 /* 378 * If we're patching in or out the fallback flush we need to be careful about the 379 * order in which we patch instructions. That's because it's possible we could 380 * take a page fault after patching one instruction, so the sequence of 381 * instructions must be safe even in a half patched state. 382 * 383 * To make that work, when patching in the fallback flush we patch in this order: 384 * - the mflr (dest) 385 * - the mtlr (dest + 2) 386 * - the branch (dest + 1) 387 * 388 * That ensures the sequence is safe to execute at any point. In contrast if we 389 * patch the mtlr last, it's possible we could return from the branch and not 390 * restore LR, leading to a crash later. 391 * 392 * When patching out the fallback flush (either with nops or another flush type), 393 * we patch in this order: 394 * - the branch (dest + 1) 395 * - the mtlr (dest + 2) 396 * - the mflr (dest) 397 * 398 * Note we are protected by stop_machine() from other CPUs executing the code in a 399 * semi-patched state. 400 */ 401 402 start = PTRRELOC(&__start___entry_flush_fixup); 403 end = PTRRELOC(&__stop___entry_flush_fixup); 404 i = do_patch_entry_fixups(start, end, instrs, types == L1D_FLUSH_FALLBACK, 405 &entry_flush_fallback); 406 407 start = PTRRELOC(&__start___scv_entry_flush_fixup); 408 end = PTRRELOC(&__stop___scv_entry_flush_fixup); 409 i += do_patch_entry_fixups(start, end, instrs, types == L1D_FLUSH_FALLBACK, 410 &scv_entry_flush_fallback); 411 412 printk(KERN_DEBUG "entry-flush: patched %d locations (%s flush)\n", i, 413 (types == L1D_FLUSH_NONE) ? "no" : 414 (types == L1D_FLUSH_FALLBACK) ? "fallback displacement" : 415 (types & L1D_FLUSH_ORI) ? (types & L1D_FLUSH_MTTRIG) 416 ? "ori+mttrig type" 417 : "ori type" : 418 (types & L1D_FLUSH_MTTRIG) ? "mttrig type" 419 : "unknown"); 420 421 return 0; 422} 423 424void do_entry_flush_fixups(enum l1d_flush_type types) 425{ 426 /* 427 * The call to the fallback flush can not be safely patched in/out while 428 * other CPUs are executing it. So call __do_entry_flush_fixups() on one 429 * CPU while all other CPUs spin in the stop machine core with interrupts 430 * hard disabled. 431 */ 432 stop_machine(__do_entry_flush_fixups, &types, NULL); 433} 434 435static int __do_rfi_flush_fixups(void *data) 436{ 437 enum l1d_flush_type types = *(enum l1d_flush_type *)data; 438 unsigned int instrs[3]; 439 long *start, *end; 440 int i; 441 442 start = PTRRELOC(&__start___rfi_flush_fixup); 443 end = PTRRELOC(&__stop___rfi_flush_fixup); 444 445 instrs[0] = PPC_RAW_NOP(); 446 instrs[1] = PPC_RAW_NOP(); 447 instrs[2] = PPC_RAW_NOP(); 448 449 if (types & L1D_FLUSH_FALLBACK) 450 /* b .+16 to fallback flush */ 451 instrs[0] = PPC_RAW_BRANCH(16); 452 453 i = 0; 454 if (types & L1D_FLUSH_ORI) { 455 instrs[i++] = PPC_RAW_ORI(_R31, _R31, 0); /* speculation barrier */ 456 instrs[i++] = PPC_RAW_ORI(_R30, _R30, 0); /* L1d flush */ 457 } 458 459 if (types & L1D_FLUSH_MTTRIG) 460 instrs[i++] = PPC_RAW_MTSPR(SPRN_TRIG2, _R0); 461 462 i = do_patch_fixups(start, end, instrs, ARRAY_SIZE(instrs)); 463 464 printk(KERN_DEBUG "rfi-flush: patched %d locations (%s flush)\n", i, 465 (types == L1D_FLUSH_NONE) ? "no" : 466 (types == L1D_FLUSH_FALLBACK) ? "fallback displacement" : 467 (types & L1D_FLUSH_ORI) ? (types & L1D_FLUSH_MTTRIG) 468 ? "ori+mttrig type" 469 : "ori type" : 470 (types & L1D_FLUSH_MTTRIG) ? "mttrig type" 471 : "unknown"); 472 473 return 0; 474} 475 476void do_rfi_flush_fixups(enum l1d_flush_type types) 477{ 478 /* 479 * stop_machine gets all CPUs out of the interrupt exit handler same 480 * as do_stf_barrier_fixups. do_rfi_flush_fixups patching can run 481 * without stop_machine, so this could be achieved with a broadcast 482 * IPI instead, but this matches the stf sequence. 483 */ 484 485 // Prevent static key update races with do_stf_barrier_fixups() 486 mutex_lock(&exit_flush_lock); 487 static_branch_enable(&interrupt_exit_not_reentrant); 488 489 stop_machine(__do_rfi_flush_fixups, &types, NULL); 490 491 if (types & L1D_FLUSH_FALLBACK) 492 rfi_exit_reentrant = false; 493 else 494 rfi_exit_reentrant = true; 495 496 if (stf_exit_reentrant && rfi_exit_reentrant) 497 static_branch_disable(&interrupt_exit_not_reentrant); 498 499 mutex_unlock(&exit_flush_lock); 500} 501 502void do_barrier_nospec_fixups_range(bool enable, void *fixup_start, void *fixup_end) 503{ 504 unsigned int instr; 505 long *start, *end; 506 int i; 507 508 start = fixup_start; 509 end = fixup_end; 510 511 instr = PPC_RAW_NOP(); 512 513 if (enable) { 514 pr_info("barrier-nospec: using ORI speculation barrier\n"); 515 instr = PPC_RAW_ORI(_R31, _R31, 0); /* speculation barrier */ 516 } 517 518 i = do_patch_fixups(start, end, &instr, 1); 519 520 printk(KERN_DEBUG "barrier-nospec: patched %d locations\n", i); 521} 522 523#endif /* CONFIG_PPC_BOOK3S_64 */ 524 525#ifdef CONFIG_PPC_BARRIER_NOSPEC 526void do_barrier_nospec_fixups(bool enable) 527{ 528 void *start, *end; 529 530 start = PTRRELOC(&__start___barrier_nospec_fixup); 531 end = PTRRELOC(&__stop___barrier_nospec_fixup); 532 533 do_barrier_nospec_fixups_range(enable, start, end); 534} 535#endif /* CONFIG_PPC_BARRIER_NOSPEC */ 536 537#ifdef CONFIG_PPC_E500 538void do_barrier_nospec_fixups_range(bool enable, void *fixup_start, void *fixup_end) 539{ 540 unsigned int instr[2]; 541 long *start, *end; 542 int i; 543 544 start = fixup_start; 545 end = fixup_end; 546 547 instr[0] = PPC_RAW_NOP(); 548 instr[1] = PPC_RAW_NOP(); 549 550 if (enable) { 551 pr_info("barrier-nospec: using isync; sync as speculation barrier\n"); 552 instr[0] = PPC_RAW_ISYNC(); 553 instr[1] = PPC_RAW_SYNC(); 554 } 555 556 i = do_patch_fixups(start, end, instr, ARRAY_SIZE(instr)); 557 558 printk(KERN_DEBUG "barrier-nospec: patched %d locations\n", i); 559} 560 561static void __init patch_btb_flush_section(long *curr) 562{ 563 unsigned int *start, *end; 564 565 start = (void *)curr + *curr; 566 end = (void *)curr + *(curr + 1); 567 for (; start < end; start++) { 568 pr_devel("patching dest %lx\n", (unsigned long)start); 569 patch_instruction(start, ppc_inst(PPC_RAW_NOP())); 570 } 571} 572 573void __init do_btb_flush_fixups(void) 574{ 575 long *start, *end; 576 577 start = PTRRELOC(&__start__btb_flush_fixup); 578 end = PTRRELOC(&__stop__btb_flush_fixup); 579 580 for (; start < end; start += 2) 581 patch_btb_flush_section(start); 582} 583#endif /* CONFIG_PPC_E500 */ 584 585void do_lwsync_fixups(unsigned long value, void *fixup_start, void *fixup_end) 586{ 587 long *start, *end; 588 u32 *dest; 589 590 if (!(value & CPU_FTR_LWSYNC)) 591 return ; 592 593 start = fixup_start; 594 end = fixup_end; 595 596 for (; start < end; start++) { 597 dest = (void *)start + *start; 598 raw_patch_instruction(dest, ppc_inst(PPC_INST_LWSYNC)); 599 } 600} 601 602static void __init do_final_fixups(void) 603{ 604#if defined(CONFIG_PPC64) && defined(CONFIG_RELOCATABLE) 605 ppc_inst_t inst; 606 u32 *src, *dest, *end; 607 608 if (PHYSICAL_START == 0) 609 return; 610 611 src = (u32 *)(KERNELBASE + PHYSICAL_START); 612 dest = (u32 *)KERNELBASE; 613 end = (void *)src + (__end_interrupts - _stext); 614 615 while (src < end) { 616 inst = ppc_inst_read(src); 617 raw_patch_instruction(dest, inst); 618 src = ppc_inst_next(src, src); 619 dest = ppc_inst_next(dest, dest); 620 } 621#endif 622} 623 624static unsigned long __initdata saved_cpu_features; 625static unsigned int __initdata saved_mmu_features; 626#ifdef CONFIG_PPC64 627static unsigned long __initdata saved_firmware_features; 628#endif 629 630void __init apply_feature_fixups(void) 631{ 632 struct cpu_spec *spec = PTRRELOC(*PTRRELOC(&cur_cpu_spec)); 633 634 *PTRRELOC(&saved_cpu_features) = spec->cpu_features; 635 *PTRRELOC(&saved_mmu_features) = spec->mmu_features; 636 637 /* 638 * Apply the CPU-specific and firmware specific fixups to kernel text 639 * (nop out sections not relevant to this CPU or this firmware). 640 */ 641 do_feature_fixups(spec->cpu_features, 642 PTRRELOC(&__start___ftr_fixup), 643 PTRRELOC(&__stop___ftr_fixup)); 644 645 do_feature_fixups(spec->mmu_features, 646 PTRRELOC(&__start___mmu_ftr_fixup), 647 PTRRELOC(&__stop___mmu_ftr_fixup)); 648 649 do_lwsync_fixups(spec->cpu_features, 650 PTRRELOC(&__start___lwsync_fixup), 651 PTRRELOC(&__stop___lwsync_fixup)); 652 653#ifdef CONFIG_PPC64 654 saved_firmware_features = powerpc_firmware_features; 655 do_feature_fixups(powerpc_firmware_features, 656 &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup); 657#endif 658 do_final_fixups(); 659} 660 661void __init update_mmu_feature_fixups(unsigned long mask) 662{ 663 saved_mmu_features &= ~mask; 664 saved_mmu_features |= cur_cpu_spec->mmu_features & mask; 665 666 do_feature_fixups_mask(cur_cpu_spec->mmu_features, mask, 667 PTRRELOC(&__start___mmu_ftr_fixup), 668 PTRRELOC(&__stop___mmu_ftr_fixup)); 669 mmu_feature_keys_init(); 670} 671 672void __init setup_feature_keys(void) 673{ 674 /* 675 * Initialise jump label. This causes all the cpu/mmu_has_feature() 676 * checks to take on their correct polarity based on the current set of 677 * CPU/MMU features. 678 */ 679 jump_label_init(); 680 cpu_feature_keys_init(); 681 mmu_feature_keys_init(); 682} 683 684static int __init check_features(void) 685{ 686 WARN(saved_cpu_features != cur_cpu_spec->cpu_features, 687 "CPU features changed after feature patching!\n"); 688 WARN(saved_mmu_features != cur_cpu_spec->mmu_features, 689 "MMU features changed after feature patching!\n"); 690#ifdef CONFIG_PPC64 691 WARN(saved_firmware_features != powerpc_firmware_features, 692 "Firmware features changed after feature patching!\n"); 693#endif 694 695 return 0; 696} 697late_initcall(check_features); 698 699#ifdef CONFIG_FTR_FIXUP_SELFTEST 700 701#define check(x) \ 702 if (!(x)) printk("feature-fixups: test failed at line %d\n", __LINE__); 703 704static int patch_feature_section(unsigned long value, struct fixup_entry *fcur) 705{ 706 return patch_feature_section_mask(value, ~0, fcur); 707} 708 709/* This must be after the text it fixes up, vmlinux.lds.S enforces that atm */ 710static struct fixup_entry fixup; 711 712static long __init calc_offset(struct fixup_entry *entry, unsigned int *p) 713{ 714 return (unsigned long)p - (unsigned long)entry; 715} 716 717static void __init test_basic_patching(void) 718{ 719 extern unsigned int ftr_fixup_test1[]; 720 extern unsigned int end_ftr_fixup_test1[]; 721 extern unsigned int ftr_fixup_test1_orig[]; 722 extern unsigned int ftr_fixup_test1_expected[]; 723 int size = 4 * (end_ftr_fixup_test1 - ftr_fixup_test1); 724 725 fixup.value = fixup.mask = 8; 726 fixup.start_off = calc_offset(&fixup, ftr_fixup_test1 + 1); 727 fixup.end_off = calc_offset(&fixup, ftr_fixup_test1 + 2); 728 fixup.alt_start_off = fixup.alt_end_off = 0; 729 730 /* Sanity check */ 731 check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0); 732 733 /* Check we don't patch if the value matches */ 734 patch_feature_section(8, &fixup); 735 check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0); 736 737 /* Check we do patch if the value doesn't match */ 738 patch_feature_section(0, &fixup); 739 check(memcmp(ftr_fixup_test1, ftr_fixup_test1_expected, size) == 0); 740 741 /* Check we do patch if the mask doesn't match */ 742 memcpy(ftr_fixup_test1, ftr_fixup_test1_orig, size); 743 check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0); 744 patch_feature_section(~8, &fixup); 745 check(memcmp(ftr_fixup_test1, ftr_fixup_test1_expected, size) == 0); 746} 747 748static void __init test_alternative_patching(void) 749{ 750 extern unsigned int ftr_fixup_test2[]; 751 extern unsigned int end_ftr_fixup_test2[]; 752 extern unsigned int ftr_fixup_test2_orig[]; 753 extern unsigned int ftr_fixup_test2_alt[]; 754 extern unsigned int ftr_fixup_test2_expected[]; 755 int size = 4 * (end_ftr_fixup_test2 - ftr_fixup_test2); 756 757 fixup.value = fixup.mask = 0xF; 758 fixup.start_off = calc_offset(&fixup, ftr_fixup_test2 + 1); 759 fixup.end_off = calc_offset(&fixup, ftr_fixup_test2 + 2); 760 fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test2_alt); 761 fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test2_alt + 1); 762 763 /* Sanity check */ 764 check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0); 765 766 /* Check we don't patch if the value matches */ 767 patch_feature_section(0xF, &fixup); 768 check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0); 769 770 /* Check we do patch if the value doesn't match */ 771 patch_feature_section(0, &fixup); 772 check(memcmp(ftr_fixup_test2, ftr_fixup_test2_expected, size) == 0); 773 774 /* Check we do patch if the mask doesn't match */ 775 memcpy(ftr_fixup_test2, ftr_fixup_test2_orig, size); 776 check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0); 777 patch_feature_section(~0xF, &fixup); 778 check(memcmp(ftr_fixup_test2, ftr_fixup_test2_expected, size) == 0); 779} 780 781static void __init test_alternative_case_too_big(void) 782{ 783 extern unsigned int ftr_fixup_test3[]; 784 extern unsigned int end_ftr_fixup_test3[]; 785 extern unsigned int ftr_fixup_test3_orig[]; 786 extern unsigned int ftr_fixup_test3_alt[]; 787 int size = 4 * (end_ftr_fixup_test3 - ftr_fixup_test3); 788 789 fixup.value = fixup.mask = 0xC; 790 fixup.start_off = calc_offset(&fixup, ftr_fixup_test3 + 1); 791 fixup.end_off = calc_offset(&fixup, ftr_fixup_test3 + 2); 792 fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test3_alt); 793 fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test3_alt + 2); 794 795 /* Sanity check */ 796 check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0); 797 798 /* Expect nothing to be patched, and the error returned to us */ 799 check(patch_feature_section(0xF, &fixup) == 1); 800 check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0); 801 check(patch_feature_section(0, &fixup) == 1); 802 check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0); 803 check(patch_feature_section(~0xF, &fixup) == 1); 804 check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0); 805} 806 807static void __init test_alternative_case_too_small(void) 808{ 809 extern unsigned int ftr_fixup_test4[]; 810 extern unsigned int end_ftr_fixup_test4[]; 811 extern unsigned int ftr_fixup_test4_orig[]; 812 extern unsigned int ftr_fixup_test4_alt[]; 813 extern unsigned int ftr_fixup_test4_expected[]; 814 int size = 4 * (end_ftr_fixup_test4 - ftr_fixup_test4); 815 unsigned long flag; 816 817 /* Check a high-bit flag */ 818 flag = 1UL << ((sizeof(unsigned long) - 1) * 8); 819 fixup.value = fixup.mask = flag; 820 fixup.start_off = calc_offset(&fixup, ftr_fixup_test4 + 1); 821 fixup.end_off = calc_offset(&fixup, ftr_fixup_test4 + 5); 822 fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test4_alt); 823 fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test4_alt + 2); 824 825 /* Sanity check */ 826 check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0); 827 828 /* Check we don't patch if the value matches */ 829 patch_feature_section(flag, &fixup); 830 check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0); 831 832 /* Check we do patch if the value doesn't match */ 833 patch_feature_section(0, &fixup); 834 check(memcmp(ftr_fixup_test4, ftr_fixup_test4_expected, size) == 0); 835 836 /* Check we do patch if the mask doesn't match */ 837 memcpy(ftr_fixup_test4, ftr_fixup_test4_orig, size); 838 check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0); 839 patch_feature_section(~flag, &fixup); 840 check(memcmp(ftr_fixup_test4, ftr_fixup_test4_expected, size) == 0); 841} 842 843static void test_alternative_case_with_branch(void) 844{ 845 extern unsigned int ftr_fixup_test5[]; 846 extern unsigned int end_ftr_fixup_test5[]; 847 extern unsigned int ftr_fixup_test5_expected[]; 848 int size = 4 * (end_ftr_fixup_test5 - ftr_fixup_test5); 849 850 check(memcmp(ftr_fixup_test5, ftr_fixup_test5_expected, size) == 0); 851} 852 853static void __init test_alternative_case_with_external_branch(void) 854{ 855 extern unsigned int ftr_fixup_test6[]; 856 extern unsigned int end_ftr_fixup_test6[]; 857 extern unsigned int ftr_fixup_test6_expected[]; 858 int size = 4 * (end_ftr_fixup_test6 - ftr_fixup_test6); 859 860 check(memcmp(ftr_fixup_test6, ftr_fixup_test6_expected, size) == 0); 861} 862 863static void __init test_alternative_case_with_branch_to_end(void) 864{ 865 extern unsigned int ftr_fixup_test7[]; 866 extern unsigned int end_ftr_fixup_test7[]; 867 extern unsigned int ftr_fixup_test7_expected[]; 868 int size = 4 * (end_ftr_fixup_test7 - ftr_fixup_test7); 869 870 check(memcmp(ftr_fixup_test7, ftr_fixup_test7_expected, size) == 0); 871} 872 873static void __init test_cpu_macros(void) 874{ 875 extern u8 ftr_fixup_test_FTR_macros[]; 876 extern u8 ftr_fixup_test_FTR_macros_expected[]; 877 unsigned long size = ftr_fixup_test_FTR_macros_expected - 878 ftr_fixup_test_FTR_macros; 879 880 /* The fixups have already been done for us during boot */ 881 check(memcmp(ftr_fixup_test_FTR_macros, 882 ftr_fixup_test_FTR_macros_expected, size) == 0); 883} 884 885static void __init test_fw_macros(void) 886{ 887#ifdef CONFIG_PPC64 888 extern u8 ftr_fixup_test_FW_FTR_macros[]; 889 extern u8 ftr_fixup_test_FW_FTR_macros_expected[]; 890 unsigned long size = ftr_fixup_test_FW_FTR_macros_expected - 891 ftr_fixup_test_FW_FTR_macros; 892 893 /* The fixups have already been done for us during boot */ 894 check(memcmp(ftr_fixup_test_FW_FTR_macros, 895 ftr_fixup_test_FW_FTR_macros_expected, size) == 0); 896#endif 897} 898 899static void __init test_lwsync_macros(void) 900{ 901 extern u8 lwsync_fixup_test[]; 902 extern u8 end_lwsync_fixup_test[]; 903 extern u8 lwsync_fixup_test_expected_LWSYNC[]; 904 extern u8 lwsync_fixup_test_expected_SYNC[]; 905 unsigned long size = end_lwsync_fixup_test - 906 lwsync_fixup_test; 907 908 /* The fixups have already been done for us during boot */ 909 if (cur_cpu_spec->cpu_features & CPU_FTR_LWSYNC) { 910 check(memcmp(lwsync_fixup_test, 911 lwsync_fixup_test_expected_LWSYNC, size) == 0); 912 } else { 913 check(memcmp(lwsync_fixup_test, 914 lwsync_fixup_test_expected_SYNC, size) == 0); 915 } 916} 917 918#ifdef CONFIG_PPC64 919static void __init test_prefix_patching(void) 920{ 921 extern unsigned int ftr_fixup_prefix1[]; 922 extern unsigned int end_ftr_fixup_prefix1[]; 923 extern unsigned int ftr_fixup_prefix1_orig[]; 924 extern unsigned int ftr_fixup_prefix1_expected[]; 925 int size = sizeof(unsigned int) * (end_ftr_fixup_prefix1 - ftr_fixup_prefix1); 926 927 fixup.value = fixup.mask = 8; 928 fixup.start_off = calc_offset(&fixup, ftr_fixup_prefix1 + 1); 929 fixup.end_off = calc_offset(&fixup, ftr_fixup_prefix1 + 3); 930 fixup.alt_start_off = fixup.alt_end_off = 0; 931 932 /* Sanity check */ 933 check(memcmp(ftr_fixup_prefix1, ftr_fixup_prefix1_orig, size) == 0); 934 935 patch_feature_section(0, &fixup); 936 check(memcmp(ftr_fixup_prefix1, ftr_fixup_prefix1_expected, size) == 0); 937 check(memcmp(ftr_fixup_prefix1, ftr_fixup_prefix1_orig, size) != 0); 938} 939 940static void __init test_prefix_alt_patching(void) 941{ 942 extern unsigned int ftr_fixup_prefix2[]; 943 extern unsigned int end_ftr_fixup_prefix2[]; 944 extern unsigned int ftr_fixup_prefix2_orig[]; 945 extern unsigned int ftr_fixup_prefix2_expected[]; 946 extern unsigned int ftr_fixup_prefix2_alt[]; 947 int size = sizeof(unsigned int) * (end_ftr_fixup_prefix2 - ftr_fixup_prefix2); 948 949 fixup.value = fixup.mask = 8; 950 fixup.start_off = calc_offset(&fixup, ftr_fixup_prefix2 + 1); 951 fixup.end_off = calc_offset(&fixup, ftr_fixup_prefix2 + 3); 952 fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_prefix2_alt); 953 fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_prefix2_alt + 2); 954 /* Sanity check */ 955 check(memcmp(ftr_fixup_prefix2, ftr_fixup_prefix2_orig, size) == 0); 956 957 patch_feature_section(0, &fixup); 958 check(memcmp(ftr_fixup_prefix2, ftr_fixup_prefix2_expected, size) == 0); 959 check(memcmp(ftr_fixup_prefix2, ftr_fixup_prefix2_orig, size) != 0); 960} 961 962static void __init test_prefix_word_alt_patching(void) 963{ 964 extern unsigned int ftr_fixup_prefix3[]; 965 extern unsigned int end_ftr_fixup_prefix3[]; 966 extern unsigned int ftr_fixup_prefix3_orig[]; 967 extern unsigned int ftr_fixup_prefix3_expected[]; 968 extern unsigned int ftr_fixup_prefix3_alt[]; 969 int size = sizeof(unsigned int) * (end_ftr_fixup_prefix3 - ftr_fixup_prefix3); 970 971 fixup.value = fixup.mask = 8; 972 fixup.start_off = calc_offset(&fixup, ftr_fixup_prefix3 + 1); 973 fixup.end_off = calc_offset(&fixup, ftr_fixup_prefix3 + 4); 974 fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_prefix3_alt); 975 fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_prefix3_alt + 3); 976 /* Sanity check */ 977 check(memcmp(ftr_fixup_prefix3, ftr_fixup_prefix3_orig, size) == 0); 978 979 patch_feature_section(0, &fixup); 980 check(memcmp(ftr_fixup_prefix3, ftr_fixup_prefix3_expected, size) == 0); 981 patch_feature_section(0, &fixup); 982 check(memcmp(ftr_fixup_prefix3, ftr_fixup_prefix3_orig, size) != 0); 983} 984#else 985static inline void test_prefix_patching(void) {} 986static inline void test_prefix_alt_patching(void) {} 987static inline void test_prefix_word_alt_patching(void) {} 988#endif /* CONFIG_PPC64 */ 989 990static int __init test_feature_fixups(void) 991{ 992 printk(KERN_DEBUG "Running feature fixup self-tests ...\n"); 993 994 test_basic_patching(); 995 test_alternative_patching(); 996 test_alternative_case_too_big(); 997 test_alternative_case_too_small(); 998 test_alternative_case_with_branch(); 999 test_alternative_case_with_external_branch(); 1000 test_alternative_case_with_branch_to_end(); 1001 test_cpu_macros(); 1002 test_fw_macros(); 1003 test_lwsync_macros(); 1004 test_prefix_patching(); 1005 test_prefix_alt_patching(); 1006 test_prefix_word_alt_patching(); 1007 1008 return 0; 1009} 1010late_initcall(test_feature_fixups); 1011 1012#endif /* CONFIG_FTR_FIXUP_SELFTEST */ 1013