1 /* 2 * Copyright 2008 Michael Ellerman, IBM Corporation. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 */ 9 10 #include <linux/kernel.h> 11 #include <linux/kprobes.h> 12 #include <linux/vmalloc.h> 13 #include <linux/init.h> 14 #include <linux/mm.h> 15 #include <linux/cpuhotplug.h> 16 #include <linux/slab.h> 17 #include <linux/uaccess.h> 18 #include <linux/kprobes.h> 19 20 #include <asm/pgtable.h> 21 #include <asm/tlbflush.h> 22 #include <asm/page.h> 23 #include <asm/code-patching.h> 24 #include <asm/setup.h> 25 26 static int __patch_instruction(unsigned int *exec_addr, unsigned int instr, 27 unsigned int *patch_addr) 28 { 29 int err; 30 31 __put_user_size(instr, patch_addr, 4, err); 32 if (err) 33 return err; 34 35 asm ("dcbst 0, %0; sync; icbi 0,%1; sync; isync" :: "r" (patch_addr), 36 "r" (exec_addr)); 37 38 return 0; 39 } 40 41 int raw_patch_instruction(unsigned int *addr, unsigned int instr) 42 { 43 return __patch_instruction(addr, instr, addr); 44 } 45 46 #ifdef CONFIG_STRICT_KERNEL_RWX 47 static DEFINE_PER_CPU(struct vm_struct *, text_poke_area); 48 49 static int text_area_cpu_up(unsigned int cpu) 50 { 51 struct vm_struct *area; 52 53 area = get_vm_area(PAGE_SIZE, VM_ALLOC); 54 if (!area) { 55 WARN_ONCE(1, "Failed to create text area for cpu %d\n", 56 cpu); 57 return -1; 58 } 59 this_cpu_write(text_poke_area, area); 60 61 return 0; 62 } 63 64 static int text_area_cpu_down(unsigned int cpu) 65 { 66 free_vm_area(this_cpu_read(text_poke_area)); 67 return 0; 68 } 69 70 /* 71 * Run as a late init call. This allows all the boot time patching to be done 72 * simply by patching the code, and then we're called here prior to 73 * mark_rodata_ro(), which happens after all init calls are run. Although 74 * BUG_ON() is rude, in this case it should only happen if ENOMEM, and we judge 75 * it as being preferable to a kernel that will crash later when someone tries 76 * to use patch_instruction(). 77 */ 78 static int __init setup_text_poke_area(void) 79 { 80 BUG_ON(!cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, 81 "powerpc/text_poke:online", text_area_cpu_up, 82 text_area_cpu_down)); 83 84 return 0; 85 } 86 late_initcall(setup_text_poke_area); 87 88 /* 89 * This can be called for kernel text or a module. 90 */ 91 static int map_patch_area(void *addr, unsigned long text_poke_addr) 92 { 93 unsigned long pfn; 94 int err; 95 96 if (is_vmalloc_addr(addr)) 97 pfn = vmalloc_to_pfn(addr); 98 else 99 pfn = __pa_symbol(addr) >> PAGE_SHIFT; 100 101 err = map_kernel_page(text_poke_addr, (pfn << PAGE_SHIFT), 102 pgprot_val(PAGE_KERNEL)); 103 104 pr_devel("Mapped addr %lx with pfn %lx:%d\n", text_poke_addr, pfn, err); 105 if (err) 106 return -1; 107 108 return 0; 109 } 110 111 static inline int unmap_patch_area(unsigned long addr) 112 { 113 pte_t *ptep; 114 pmd_t *pmdp; 115 pud_t *pudp; 116 pgd_t *pgdp; 117 118 pgdp = pgd_offset_k(addr); 119 if (unlikely(!pgdp)) 120 return -EINVAL; 121 122 pudp = pud_offset(pgdp, addr); 123 if (unlikely(!pudp)) 124 return -EINVAL; 125 126 pmdp = pmd_offset(pudp, addr); 127 if (unlikely(!pmdp)) 128 return -EINVAL; 129 130 ptep = pte_offset_kernel(pmdp, addr); 131 if (unlikely(!ptep)) 132 return -EINVAL; 133 134 pr_devel("clearing mm %p, pte %p, addr %lx\n", &init_mm, ptep, addr); 135 136 /* 137 * In hash, pte_clear flushes the tlb, in radix, we have to 138 */ 139 pte_clear(&init_mm, addr, ptep); 140 flush_tlb_kernel_range(addr, addr + PAGE_SIZE); 141 142 return 0; 143 } 144 145 static int do_patch_instruction(unsigned int *addr, unsigned int instr) 146 { 147 int err; 148 unsigned int *patch_addr = NULL; 149 unsigned long flags; 150 unsigned long text_poke_addr; 151 unsigned long kaddr = (unsigned long)addr; 152 153 /* 154 * During early early boot patch_instruction is called 155 * when text_poke_area is not ready, but we still need 156 * to allow patching. We just do the plain old patching 157 */ 158 if (!this_cpu_read(text_poke_area)) 159 return raw_patch_instruction(addr, instr); 160 161 local_irq_save(flags); 162 163 text_poke_addr = (unsigned long)__this_cpu_read(text_poke_area)->addr; 164 if (map_patch_area(addr, text_poke_addr)) { 165 err = -1; 166 goto out; 167 } 168 169 patch_addr = (unsigned int *)(text_poke_addr) + 170 ((kaddr & ~PAGE_MASK) / sizeof(unsigned int)); 171 172 __patch_instruction(addr, instr, patch_addr); 173 174 err = unmap_patch_area(text_poke_addr); 175 if (err) 176 pr_warn("failed to unmap %lx\n", text_poke_addr); 177 178 out: 179 local_irq_restore(flags); 180 181 return err; 182 } 183 #else /* !CONFIG_STRICT_KERNEL_RWX */ 184 185 static int do_patch_instruction(unsigned int *addr, unsigned int instr) 186 { 187 return raw_patch_instruction(addr, instr); 188 } 189 190 #endif /* CONFIG_STRICT_KERNEL_RWX */ 191 192 int patch_instruction(unsigned int *addr, unsigned int instr) 193 { 194 /* Make sure we aren't patching a freed init section */ 195 if (init_mem_is_free && init_section_contains(addr, 4)) { 196 pr_debug("Skipping init section patching addr: 0x%px\n", addr); 197 return 0; 198 } 199 return do_patch_instruction(addr, instr); 200 } 201 NOKPROBE_SYMBOL(patch_instruction); 202 203 int patch_branch(unsigned int *addr, unsigned long target, int flags) 204 { 205 return patch_instruction(addr, create_branch(addr, target, flags)); 206 } 207 208 int patch_branch_site(s32 *site, unsigned long target, int flags) 209 { 210 unsigned int *addr; 211 212 addr = (unsigned int *)((unsigned long)site + *site); 213 return patch_instruction(addr, create_branch(addr, target, flags)); 214 } 215 216 int patch_instruction_site(s32 *site, unsigned int instr) 217 { 218 unsigned int *addr; 219 220 addr = (unsigned int *)((unsigned long)site + *site); 221 return patch_instruction(addr, instr); 222 } 223 224 bool is_offset_in_branch_range(long offset) 225 { 226 /* 227 * Powerpc branch instruction is : 228 * 229 * 0 6 30 31 230 * +---------+----------------+---+---+ 231 * | opcode | LI |AA |LK | 232 * +---------+----------------+---+---+ 233 * Where AA = 0 and LK = 0 234 * 235 * LI is a signed 24 bits integer. The real branch offset is computed 236 * by: imm32 = SignExtend(LI:'0b00', 32); 237 * 238 * So the maximum forward branch should be: 239 * (0x007fffff << 2) = 0x01fffffc = 0x1fffffc 240 * The maximum backward branch should be: 241 * (0xff800000 << 2) = 0xfe000000 = -0x2000000 242 */ 243 return (offset >= -0x2000000 && offset <= 0x1fffffc && !(offset & 0x3)); 244 } 245 246 /* 247 * Helper to check if a given instruction is a conditional branch 248 * Derived from the conditional checks in analyse_instr() 249 */ 250 bool is_conditional_branch(unsigned int instr) 251 { 252 unsigned int opcode = instr >> 26; 253 254 if (opcode == 16) /* bc, bca, bcl, bcla */ 255 return true; 256 if (opcode == 19) { 257 switch ((instr >> 1) & 0x3ff) { 258 case 16: /* bclr, bclrl */ 259 case 528: /* bcctr, bcctrl */ 260 case 560: /* bctar, bctarl */ 261 return true; 262 } 263 } 264 return false; 265 } 266 NOKPROBE_SYMBOL(is_conditional_branch); 267 268 unsigned int create_branch(const unsigned int *addr, 269 unsigned long target, int flags) 270 { 271 unsigned int instruction; 272 long offset; 273 274 offset = target; 275 if (! (flags & BRANCH_ABSOLUTE)) 276 offset = offset - (unsigned long)addr; 277 278 /* Check we can represent the target in the instruction format */ 279 if (!is_offset_in_branch_range(offset)) 280 return 0; 281 282 /* Mask out the flags and target, so they don't step on each other. */ 283 instruction = 0x48000000 | (flags & 0x3) | (offset & 0x03FFFFFC); 284 285 return instruction; 286 } 287 288 unsigned int create_cond_branch(const unsigned int *addr, 289 unsigned long target, int flags) 290 { 291 unsigned int instruction; 292 long offset; 293 294 offset = target; 295 if (! (flags & BRANCH_ABSOLUTE)) 296 offset = offset - (unsigned long)addr; 297 298 /* Check we can represent the target in the instruction format */ 299 if (offset < -0x8000 || offset > 0x7FFF || offset & 0x3) 300 return 0; 301 302 /* Mask out the flags and target, so they don't step on each other. */ 303 instruction = 0x40000000 | (flags & 0x3FF0003) | (offset & 0xFFFC); 304 305 return instruction; 306 } 307 308 static unsigned int branch_opcode(unsigned int instr) 309 { 310 return (instr >> 26) & 0x3F; 311 } 312 313 static int instr_is_branch_iform(unsigned int instr) 314 { 315 return branch_opcode(instr) == 18; 316 } 317 318 static int instr_is_branch_bform(unsigned int instr) 319 { 320 return branch_opcode(instr) == 16; 321 } 322 323 int instr_is_relative_branch(unsigned int instr) 324 { 325 if (instr & BRANCH_ABSOLUTE) 326 return 0; 327 328 return instr_is_branch_iform(instr) || instr_is_branch_bform(instr); 329 } 330 331 int instr_is_relative_link_branch(unsigned int instr) 332 { 333 return instr_is_relative_branch(instr) && (instr & BRANCH_SET_LINK); 334 } 335 336 static unsigned long branch_iform_target(const unsigned int *instr) 337 { 338 signed long imm; 339 340 imm = *instr & 0x3FFFFFC; 341 342 /* If the top bit of the immediate value is set this is negative */ 343 if (imm & 0x2000000) 344 imm -= 0x4000000; 345 346 if ((*instr & BRANCH_ABSOLUTE) == 0) 347 imm += (unsigned long)instr; 348 349 return (unsigned long)imm; 350 } 351 352 static unsigned long branch_bform_target(const unsigned int *instr) 353 { 354 signed long imm; 355 356 imm = *instr & 0xFFFC; 357 358 /* If the top bit of the immediate value is set this is negative */ 359 if (imm & 0x8000) 360 imm -= 0x10000; 361 362 if ((*instr & BRANCH_ABSOLUTE) == 0) 363 imm += (unsigned long)instr; 364 365 return (unsigned long)imm; 366 } 367 368 unsigned long branch_target(const unsigned int *instr) 369 { 370 if (instr_is_branch_iform(*instr)) 371 return branch_iform_target(instr); 372 else if (instr_is_branch_bform(*instr)) 373 return branch_bform_target(instr); 374 375 return 0; 376 } 377 378 int instr_is_branch_to_addr(const unsigned int *instr, unsigned long addr) 379 { 380 if (instr_is_branch_iform(*instr) || instr_is_branch_bform(*instr)) 381 return branch_target(instr) == addr; 382 383 return 0; 384 } 385 386 unsigned int translate_branch(const unsigned int *dest, const unsigned int *src) 387 { 388 unsigned long target; 389 390 target = branch_target(src); 391 392 if (instr_is_branch_iform(*src)) 393 return create_branch(dest, target, *src); 394 else if (instr_is_branch_bform(*src)) 395 return create_cond_branch(dest, target, *src); 396 397 return 0; 398 } 399 400 #ifdef CONFIG_PPC_BOOK3E_64 401 void __patch_exception(int exc, unsigned long addr) 402 { 403 extern unsigned int interrupt_base_book3e; 404 unsigned int *ibase = &interrupt_base_book3e; 405 406 /* Our exceptions vectors start with a NOP and -then- a branch 407 * to deal with single stepping from userspace which stops on 408 * the second instruction. Thus we need to patch the second 409 * instruction of the exception, not the first one 410 */ 411 412 patch_branch(ibase + (exc / 4) + 1, addr, 0); 413 } 414 #endif 415 416 #ifdef CONFIG_CODE_PATCHING_SELFTEST 417 418 static void __init test_trampoline(void) 419 { 420 asm ("nop;\n"); 421 } 422 423 #define check(x) \ 424 if (!(x)) printk("code-patching: test failed at line %d\n", __LINE__); 425 426 static void __init test_branch_iform(void) 427 { 428 unsigned int instr; 429 unsigned long addr; 430 431 addr = (unsigned long)&instr; 432 433 /* The simplest case, branch to self, no flags */ 434 check(instr_is_branch_iform(0x48000000)); 435 /* All bits of target set, and flags */ 436 check(instr_is_branch_iform(0x4bffffff)); 437 /* High bit of opcode set, which is wrong */ 438 check(!instr_is_branch_iform(0xcbffffff)); 439 /* Middle bits of opcode set, which is wrong */ 440 check(!instr_is_branch_iform(0x7bffffff)); 441 442 /* Simplest case, branch to self with link */ 443 check(instr_is_branch_iform(0x48000001)); 444 /* All bits of targets set */ 445 check(instr_is_branch_iform(0x4bfffffd)); 446 /* Some bits of targets set */ 447 check(instr_is_branch_iform(0x4bff00fd)); 448 /* Must be a valid branch to start with */ 449 check(!instr_is_branch_iform(0x7bfffffd)); 450 451 /* Absolute branch to 0x100 */ 452 instr = 0x48000103; 453 check(instr_is_branch_to_addr(&instr, 0x100)); 454 /* Absolute branch to 0x420fc */ 455 instr = 0x480420ff; 456 check(instr_is_branch_to_addr(&instr, 0x420fc)); 457 /* Maximum positive relative branch, + 20MB - 4B */ 458 instr = 0x49fffffc; 459 check(instr_is_branch_to_addr(&instr, addr + 0x1FFFFFC)); 460 /* Smallest negative relative branch, - 4B */ 461 instr = 0x4bfffffc; 462 check(instr_is_branch_to_addr(&instr, addr - 4)); 463 /* Largest negative relative branch, - 32 MB */ 464 instr = 0x4a000000; 465 check(instr_is_branch_to_addr(&instr, addr - 0x2000000)); 466 467 /* Branch to self, with link */ 468 instr = create_branch(&instr, addr, BRANCH_SET_LINK); 469 check(instr_is_branch_to_addr(&instr, addr)); 470 471 /* Branch to self - 0x100, with link */ 472 instr = create_branch(&instr, addr - 0x100, BRANCH_SET_LINK); 473 check(instr_is_branch_to_addr(&instr, addr - 0x100)); 474 475 /* Branch to self + 0x100, no link */ 476 instr = create_branch(&instr, addr + 0x100, 0); 477 check(instr_is_branch_to_addr(&instr, addr + 0x100)); 478 479 /* Maximum relative negative offset, - 32 MB */ 480 instr = create_branch(&instr, addr - 0x2000000, BRANCH_SET_LINK); 481 check(instr_is_branch_to_addr(&instr, addr - 0x2000000)); 482 483 /* Out of range relative negative offset, - 32 MB + 4*/ 484 instr = create_branch(&instr, addr - 0x2000004, BRANCH_SET_LINK); 485 check(instr == 0); 486 487 /* Out of range relative positive offset, + 32 MB */ 488 instr = create_branch(&instr, addr + 0x2000000, BRANCH_SET_LINK); 489 check(instr == 0); 490 491 /* Unaligned target */ 492 instr = create_branch(&instr, addr + 3, BRANCH_SET_LINK); 493 check(instr == 0); 494 495 /* Check flags are masked correctly */ 496 instr = create_branch(&instr, addr, 0xFFFFFFFC); 497 check(instr_is_branch_to_addr(&instr, addr)); 498 check(instr == 0x48000000); 499 } 500 501 static void __init test_create_function_call(void) 502 { 503 unsigned int *iptr; 504 unsigned long dest; 505 506 /* Check we can create a function call */ 507 iptr = (unsigned int *)ppc_function_entry(test_trampoline); 508 dest = ppc_function_entry(test_create_function_call); 509 patch_instruction(iptr, create_branch(iptr, dest, BRANCH_SET_LINK)); 510 check(instr_is_branch_to_addr(iptr, dest)); 511 } 512 513 static void __init test_branch_bform(void) 514 { 515 unsigned long addr; 516 unsigned int *iptr, instr, flags; 517 518 iptr = &instr; 519 addr = (unsigned long)iptr; 520 521 /* The simplest case, branch to self, no flags */ 522 check(instr_is_branch_bform(0x40000000)); 523 /* All bits of target set, and flags */ 524 check(instr_is_branch_bform(0x43ffffff)); 525 /* High bit of opcode set, which is wrong */ 526 check(!instr_is_branch_bform(0xc3ffffff)); 527 /* Middle bits of opcode set, which is wrong */ 528 check(!instr_is_branch_bform(0x7bffffff)); 529 530 /* Absolute conditional branch to 0x100 */ 531 instr = 0x43ff0103; 532 check(instr_is_branch_to_addr(&instr, 0x100)); 533 /* Absolute conditional branch to 0x20fc */ 534 instr = 0x43ff20ff; 535 check(instr_is_branch_to_addr(&instr, 0x20fc)); 536 /* Maximum positive relative conditional branch, + 32 KB - 4B */ 537 instr = 0x43ff7ffc; 538 check(instr_is_branch_to_addr(&instr, addr + 0x7FFC)); 539 /* Smallest negative relative conditional branch, - 4B */ 540 instr = 0x43fffffc; 541 check(instr_is_branch_to_addr(&instr, addr - 4)); 542 /* Largest negative relative conditional branch, - 32 KB */ 543 instr = 0x43ff8000; 544 check(instr_is_branch_to_addr(&instr, addr - 0x8000)); 545 546 /* All condition code bits set & link */ 547 flags = 0x3ff000 | BRANCH_SET_LINK; 548 549 /* Branch to self */ 550 instr = create_cond_branch(iptr, addr, flags); 551 check(instr_is_branch_to_addr(&instr, addr)); 552 553 /* Branch to self - 0x100 */ 554 instr = create_cond_branch(iptr, addr - 0x100, flags); 555 check(instr_is_branch_to_addr(&instr, addr - 0x100)); 556 557 /* Branch to self + 0x100 */ 558 instr = create_cond_branch(iptr, addr + 0x100, flags); 559 check(instr_is_branch_to_addr(&instr, addr + 0x100)); 560 561 /* Maximum relative negative offset, - 32 KB */ 562 instr = create_cond_branch(iptr, addr - 0x8000, flags); 563 check(instr_is_branch_to_addr(&instr, addr - 0x8000)); 564 565 /* Out of range relative negative offset, - 32 KB + 4*/ 566 instr = create_cond_branch(iptr, addr - 0x8004, flags); 567 check(instr == 0); 568 569 /* Out of range relative positive offset, + 32 KB */ 570 instr = create_cond_branch(iptr, addr + 0x8000, flags); 571 check(instr == 0); 572 573 /* Unaligned target */ 574 instr = create_cond_branch(iptr, addr + 3, flags); 575 check(instr == 0); 576 577 /* Check flags are masked correctly */ 578 instr = create_cond_branch(iptr, addr, 0xFFFFFFFC); 579 check(instr_is_branch_to_addr(&instr, addr)); 580 check(instr == 0x43FF0000); 581 } 582 583 static void __init test_translate_branch(void) 584 { 585 unsigned long addr; 586 unsigned int *p, *q; 587 void *buf; 588 589 buf = vmalloc(PAGE_ALIGN(0x2000000 + 1)); 590 check(buf); 591 if (!buf) 592 return; 593 594 /* Simple case, branch to self moved a little */ 595 p = buf; 596 addr = (unsigned long)p; 597 patch_branch(p, addr, 0); 598 check(instr_is_branch_to_addr(p, addr)); 599 q = p + 1; 600 patch_instruction(q, translate_branch(q, p)); 601 check(instr_is_branch_to_addr(q, addr)); 602 603 /* Maximum negative case, move b . to addr + 32 MB */ 604 p = buf; 605 addr = (unsigned long)p; 606 patch_branch(p, addr, 0); 607 q = buf + 0x2000000; 608 patch_instruction(q, translate_branch(q, p)); 609 check(instr_is_branch_to_addr(p, addr)); 610 check(instr_is_branch_to_addr(q, addr)); 611 check(*q == 0x4a000000); 612 613 /* Maximum positive case, move x to x - 32 MB + 4 */ 614 p = buf + 0x2000000; 615 addr = (unsigned long)p; 616 patch_branch(p, addr, 0); 617 q = buf + 4; 618 patch_instruction(q, translate_branch(q, p)); 619 check(instr_is_branch_to_addr(p, addr)); 620 check(instr_is_branch_to_addr(q, addr)); 621 check(*q == 0x49fffffc); 622 623 /* Jump to x + 16 MB moved to x + 20 MB */ 624 p = buf; 625 addr = 0x1000000 + (unsigned long)buf; 626 patch_branch(p, addr, BRANCH_SET_LINK); 627 q = buf + 0x1400000; 628 patch_instruction(q, translate_branch(q, p)); 629 check(instr_is_branch_to_addr(p, addr)); 630 check(instr_is_branch_to_addr(q, addr)); 631 632 /* Jump to x + 16 MB moved to x - 16 MB + 4 */ 633 p = buf + 0x1000000; 634 addr = 0x2000000 + (unsigned long)buf; 635 patch_branch(p, addr, 0); 636 q = buf + 4; 637 patch_instruction(q, translate_branch(q, p)); 638 check(instr_is_branch_to_addr(p, addr)); 639 check(instr_is_branch_to_addr(q, addr)); 640 641 642 /* Conditional branch tests */ 643 644 /* Simple case, branch to self moved a little */ 645 p = buf; 646 addr = (unsigned long)p; 647 patch_instruction(p, create_cond_branch(p, addr, 0)); 648 check(instr_is_branch_to_addr(p, addr)); 649 q = p + 1; 650 patch_instruction(q, translate_branch(q, p)); 651 check(instr_is_branch_to_addr(q, addr)); 652 653 /* Maximum negative case, move b . to addr + 32 KB */ 654 p = buf; 655 addr = (unsigned long)p; 656 patch_instruction(p, create_cond_branch(p, addr, 0xFFFFFFFC)); 657 q = buf + 0x8000; 658 patch_instruction(q, translate_branch(q, p)); 659 check(instr_is_branch_to_addr(p, addr)); 660 check(instr_is_branch_to_addr(q, addr)); 661 check(*q == 0x43ff8000); 662 663 /* Maximum positive case, move x to x - 32 KB + 4 */ 664 p = buf + 0x8000; 665 addr = (unsigned long)p; 666 patch_instruction(p, create_cond_branch(p, addr, 0xFFFFFFFC)); 667 q = buf + 4; 668 patch_instruction(q, translate_branch(q, p)); 669 check(instr_is_branch_to_addr(p, addr)); 670 check(instr_is_branch_to_addr(q, addr)); 671 check(*q == 0x43ff7ffc); 672 673 /* Jump to x + 12 KB moved to x + 20 KB */ 674 p = buf; 675 addr = 0x3000 + (unsigned long)buf; 676 patch_instruction(p, create_cond_branch(p, addr, BRANCH_SET_LINK)); 677 q = buf + 0x5000; 678 patch_instruction(q, translate_branch(q, p)); 679 check(instr_is_branch_to_addr(p, addr)); 680 check(instr_is_branch_to_addr(q, addr)); 681 682 /* Jump to x + 8 KB moved to x - 8 KB + 4 */ 683 p = buf + 0x2000; 684 addr = 0x4000 + (unsigned long)buf; 685 patch_instruction(p, create_cond_branch(p, addr, 0)); 686 q = buf + 4; 687 patch_instruction(q, translate_branch(q, p)); 688 check(instr_is_branch_to_addr(p, addr)); 689 check(instr_is_branch_to_addr(q, addr)); 690 691 /* Free the buffer we were using */ 692 vfree(buf); 693 } 694 695 static int __init test_code_patching(void) 696 { 697 printk(KERN_DEBUG "Running code patching self-tests ...\n"); 698 699 test_branch_iform(); 700 test_branch_bform(); 701 test_create_function_call(); 702 test_translate_branch(); 703 704 return 0; 705 } 706 late_initcall(test_code_patching); 707 708 #endif /* CONFIG_CODE_PATCHING_SELFTEST */ 709