1 /* 2 * Derived from "arch/i386/kernel/process.c" 3 * Copyright (C) 1995 Linus Torvalds 4 * 5 * Updated and modified by Cort Dougan (cort@cs.nmt.edu) and 6 * Paul Mackerras (paulus@cs.anu.edu.au) 7 * 8 * PowerPC version 9 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) 10 * 11 * This program is free software; you can redistribute it and/or 12 * modify it under the terms of the GNU General Public License 13 * as published by the Free Software Foundation; either version 14 * 2 of the License, or (at your option) any later version. 15 */ 16 17 #include <linux/errno.h> 18 #include <linux/sched.h> 19 #include <linux/kernel.h> 20 #include <linux/mm.h> 21 #include <linux/smp.h> 22 #include <linux/stddef.h> 23 #include <linux/unistd.h> 24 #include <linux/ptrace.h> 25 #include <linux/slab.h> 26 #include <linux/user.h> 27 #include <linux/elf.h> 28 #include <linux/init.h> 29 #include <linux/prctl.h> 30 #include <linux/init_task.h> 31 #include <linux/export.h> 32 #include <linux/kallsyms.h> 33 #include <linux/mqueue.h> 34 #include <linux/hardirq.h> 35 #include <linux/utsname.h> 36 #include <linux/ftrace.h> 37 #include <linux/kernel_stat.h> 38 #include <linux/personality.h> 39 #include <linux/random.h> 40 #include <linux/hw_breakpoint.h> 41 42 #include <asm/pgtable.h> 43 #include <asm/uaccess.h> 44 #include <asm/io.h> 45 #include <asm/processor.h> 46 #include <asm/mmu.h> 47 #include <asm/prom.h> 48 #include <asm/machdep.h> 49 #include <asm/time.h> 50 #include <asm/runlatch.h> 51 #include <asm/syscalls.h> 52 #include <asm/switch_to.h> 53 #include <asm/tm.h> 54 #include <asm/debug.h> 55 #ifdef CONFIG_PPC64 56 #include <asm/firmware.h> 57 #endif 58 #include <linux/kprobes.h> 59 #include <linux/kdebug.h> 60 61 /* Transactional Memory debug */ 62 #ifdef TM_DEBUG_SW 63 #define TM_DEBUG(x...) printk(KERN_INFO x) 64 #else 65 #define TM_DEBUG(x...) do { } while(0) 66 #endif 67 68 extern unsigned long _get_SP(void); 69 70 #ifndef CONFIG_SMP 71 struct task_struct *last_task_used_math = NULL; 72 struct task_struct *last_task_used_altivec = NULL; 73 struct task_struct *last_task_used_vsx = NULL; 74 struct task_struct *last_task_used_spe = NULL; 75 #endif 76 77 #ifdef CONFIG_PPC_FPU 78 /* 79 * Make sure the floating-point register state in the 80 * the thread_struct is up to date for task tsk. 81 */ 82 void flush_fp_to_thread(struct task_struct *tsk) 83 { 84 if (tsk->thread.regs) { 85 /* 86 * We need to disable preemption here because if we didn't, 87 * another process could get scheduled after the regs->msr 88 * test but before we have finished saving the FP registers 89 * to the thread_struct. That process could take over the 90 * FPU, and then when we get scheduled again we would store 91 * bogus values for the remaining FP registers. 92 */ 93 preempt_disable(); 94 if (tsk->thread.regs->msr & MSR_FP) { 95 #ifdef CONFIG_SMP 96 /* 97 * This should only ever be called for current or 98 * for a stopped child process. Since we save away 99 * the FP register state on context switch on SMP, 100 * there is something wrong if a stopped child appears 101 * to still have its FP state in the CPU registers. 102 */ 103 BUG_ON(tsk != current); 104 #endif 105 giveup_fpu(tsk); 106 } 107 preempt_enable(); 108 } 109 } 110 EXPORT_SYMBOL_GPL(flush_fp_to_thread); 111 #endif 112 113 void enable_kernel_fp(void) 114 { 115 WARN_ON(preemptible()); 116 117 #ifdef CONFIG_SMP 118 if (current->thread.regs && (current->thread.regs->msr & MSR_FP)) 119 giveup_fpu(current); 120 else 121 giveup_fpu(NULL); /* just enables FP for kernel */ 122 #else 123 giveup_fpu(last_task_used_math); 124 #endif /* CONFIG_SMP */ 125 } 126 EXPORT_SYMBOL(enable_kernel_fp); 127 128 #ifdef CONFIG_ALTIVEC 129 void enable_kernel_altivec(void) 130 { 131 WARN_ON(preemptible()); 132 133 #ifdef CONFIG_SMP 134 if (current->thread.regs && (current->thread.regs->msr & MSR_VEC)) 135 giveup_altivec(current); 136 else 137 giveup_altivec_notask(); 138 #else 139 giveup_altivec(last_task_used_altivec); 140 #endif /* CONFIG_SMP */ 141 } 142 EXPORT_SYMBOL(enable_kernel_altivec); 143 144 /* 145 * Make sure the VMX/Altivec register state in the 146 * the thread_struct is up to date for task tsk. 147 */ 148 void flush_altivec_to_thread(struct task_struct *tsk) 149 { 150 if (tsk->thread.regs) { 151 preempt_disable(); 152 if (tsk->thread.regs->msr & MSR_VEC) { 153 #ifdef CONFIG_SMP 154 BUG_ON(tsk != current); 155 #endif 156 giveup_altivec(tsk); 157 } 158 preempt_enable(); 159 } 160 } 161 EXPORT_SYMBOL_GPL(flush_altivec_to_thread); 162 #endif /* CONFIG_ALTIVEC */ 163 164 #ifdef CONFIG_VSX 165 #if 0 166 /* not currently used, but some crazy RAID module might want to later */ 167 void enable_kernel_vsx(void) 168 { 169 WARN_ON(preemptible()); 170 171 #ifdef CONFIG_SMP 172 if (current->thread.regs && (current->thread.regs->msr & MSR_VSX)) 173 giveup_vsx(current); 174 else 175 giveup_vsx(NULL); /* just enable vsx for kernel - force */ 176 #else 177 giveup_vsx(last_task_used_vsx); 178 #endif /* CONFIG_SMP */ 179 } 180 EXPORT_SYMBOL(enable_kernel_vsx); 181 #endif 182 183 void giveup_vsx(struct task_struct *tsk) 184 { 185 giveup_fpu(tsk); 186 giveup_altivec(tsk); 187 __giveup_vsx(tsk); 188 } 189 190 void flush_vsx_to_thread(struct task_struct *tsk) 191 { 192 if (tsk->thread.regs) { 193 preempt_disable(); 194 if (tsk->thread.regs->msr & MSR_VSX) { 195 #ifdef CONFIG_SMP 196 BUG_ON(tsk != current); 197 #endif 198 giveup_vsx(tsk); 199 } 200 preempt_enable(); 201 } 202 } 203 EXPORT_SYMBOL_GPL(flush_vsx_to_thread); 204 #endif /* CONFIG_VSX */ 205 206 #ifdef CONFIG_SPE 207 208 void enable_kernel_spe(void) 209 { 210 WARN_ON(preemptible()); 211 212 #ifdef CONFIG_SMP 213 if (current->thread.regs && (current->thread.regs->msr & MSR_SPE)) 214 giveup_spe(current); 215 else 216 giveup_spe(NULL); /* just enable SPE for kernel - force */ 217 #else 218 giveup_spe(last_task_used_spe); 219 #endif /* __SMP __ */ 220 } 221 EXPORT_SYMBOL(enable_kernel_spe); 222 223 void flush_spe_to_thread(struct task_struct *tsk) 224 { 225 if (tsk->thread.regs) { 226 preempt_disable(); 227 if (tsk->thread.regs->msr & MSR_SPE) { 228 #ifdef CONFIG_SMP 229 BUG_ON(tsk != current); 230 #endif 231 tsk->thread.spefscr = mfspr(SPRN_SPEFSCR); 232 giveup_spe(tsk); 233 } 234 preempt_enable(); 235 } 236 } 237 #endif /* CONFIG_SPE */ 238 239 #ifndef CONFIG_SMP 240 /* 241 * If we are doing lazy switching of CPU state (FP, altivec or SPE), 242 * and the current task has some state, discard it. 243 */ 244 void discard_lazy_cpu_state(void) 245 { 246 preempt_disable(); 247 if (last_task_used_math == current) 248 last_task_used_math = NULL; 249 #ifdef CONFIG_ALTIVEC 250 if (last_task_used_altivec == current) 251 last_task_used_altivec = NULL; 252 #endif /* CONFIG_ALTIVEC */ 253 #ifdef CONFIG_VSX 254 if (last_task_used_vsx == current) 255 last_task_used_vsx = NULL; 256 #endif /* CONFIG_VSX */ 257 #ifdef CONFIG_SPE 258 if (last_task_used_spe == current) 259 last_task_used_spe = NULL; 260 #endif 261 preempt_enable(); 262 } 263 #endif /* CONFIG_SMP */ 264 265 #ifdef CONFIG_PPC_ADV_DEBUG_REGS 266 void do_send_trap(struct pt_regs *regs, unsigned long address, 267 unsigned long error_code, int signal_code, int breakpt) 268 { 269 siginfo_t info; 270 271 current->thread.trap_nr = signal_code; 272 if (notify_die(DIE_DABR_MATCH, "dabr_match", regs, error_code, 273 11, SIGSEGV) == NOTIFY_STOP) 274 return; 275 276 /* Deliver the signal to userspace */ 277 info.si_signo = SIGTRAP; 278 info.si_errno = breakpt; /* breakpoint or watchpoint id */ 279 info.si_code = signal_code; 280 info.si_addr = (void __user *)address; 281 force_sig_info(SIGTRAP, &info, current); 282 } 283 #else /* !CONFIG_PPC_ADV_DEBUG_REGS */ 284 void do_break (struct pt_regs *regs, unsigned long address, 285 unsigned long error_code) 286 { 287 siginfo_t info; 288 289 current->thread.trap_nr = TRAP_HWBKPT; 290 if (notify_die(DIE_DABR_MATCH, "dabr_match", regs, error_code, 291 11, SIGSEGV) == NOTIFY_STOP) 292 return; 293 294 if (debugger_break_match(regs)) 295 return; 296 297 /* Clear the breakpoint */ 298 hw_breakpoint_disable(); 299 300 /* Deliver the signal to userspace */ 301 info.si_signo = SIGTRAP; 302 info.si_errno = 0; 303 info.si_code = TRAP_HWBKPT; 304 info.si_addr = (void __user *)address; 305 force_sig_info(SIGTRAP, &info, current); 306 } 307 #endif /* CONFIG_PPC_ADV_DEBUG_REGS */ 308 309 static DEFINE_PER_CPU(struct arch_hw_breakpoint, current_brk); 310 311 #ifdef CONFIG_PPC_ADV_DEBUG_REGS 312 /* 313 * Set the debug registers back to their default "safe" values. 314 */ 315 static void set_debug_reg_defaults(struct thread_struct *thread) 316 { 317 thread->iac1 = thread->iac2 = 0; 318 #if CONFIG_PPC_ADV_DEBUG_IACS > 2 319 thread->iac3 = thread->iac4 = 0; 320 #endif 321 thread->dac1 = thread->dac2 = 0; 322 #if CONFIG_PPC_ADV_DEBUG_DVCS > 0 323 thread->dvc1 = thread->dvc2 = 0; 324 #endif 325 thread->dbcr0 = 0; 326 #ifdef CONFIG_BOOKE 327 /* 328 * Force User/Supervisor bits to b11 (user-only MSR[PR]=1) 329 */ 330 thread->dbcr1 = DBCR1_IAC1US | DBCR1_IAC2US | \ 331 DBCR1_IAC3US | DBCR1_IAC4US; 332 /* 333 * Force Data Address Compare User/Supervisor bits to be User-only 334 * (0b11 MSR[PR]=1) and set all other bits in DBCR2 register to be 0. 335 */ 336 thread->dbcr2 = DBCR2_DAC1US | DBCR2_DAC2US; 337 #else 338 thread->dbcr1 = 0; 339 #endif 340 } 341 342 static void prime_debug_regs(struct thread_struct *thread) 343 { 344 /* 345 * We could have inherited MSR_DE from userspace, since 346 * it doesn't get cleared on exception entry. Make sure 347 * MSR_DE is clear before we enable any debug events. 348 */ 349 mtmsr(mfmsr() & ~MSR_DE); 350 351 mtspr(SPRN_IAC1, thread->iac1); 352 mtspr(SPRN_IAC2, thread->iac2); 353 #if CONFIG_PPC_ADV_DEBUG_IACS > 2 354 mtspr(SPRN_IAC3, thread->iac3); 355 mtspr(SPRN_IAC4, thread->iac4); 356 #endif 357 mtspr(SPRN_DAC1, thread->dac1); 358 mtspr(SPRN_DAC2, thread->dac2); 359 #if CONFIG_PPC_ADV_DEBUG_DVCS > 0 360 mtspr(SPRN_DVC1, thread->dvc1); 361 mtspr(SPRN_DVC2, thread->dvc2); 362 #endif 363 mtspr(SPRN_DBCR0, thread->dbcr0); 364 mtspr(SPRN_DBCR1, thread->dbcr1); 365 #ifdef CONFIG_BOOKE 366 mtspr(SPRN_DBCR2, thread->dbcr2); 367 #endif 368 } 369 /* 370 * Unless neither the old or new thread are making use of the 371 * debug registers, set the debug registers from the values 372 * stored in the new thread. 373 */ 374 static void switch_booke_debug_regs(struct thread_struct *new_thread) 375 { 376 if ((current->thread.dbcr0 & DBCR0_IDM) 377 || (new_thread->dbcr0 & DBCR0_IDM)) 378 prime_debug_regs(new_thread); 379 } 380 #else /* !CONFIG_PPC_ADV_DEBUG_REGS */ 381 #ifndef CONFIG_HAVE_HW_BREAKPOINT 382 static void set_debug_reg_defaults(struct thread_struct *thread) 383 { 384 thread->hw_brk.address = 0; 385 thread->hw_brk.type = 0; 386 set_breakpoint(&thread->hw_brk); 387 } 388 #endif /* !CONFIG_HAVE_HW_BREAKPOINT */ 389 #endif /* CONFIG_PPC_ADV_DEBUG_REGS */ 390 391 #ifdef CONFIG_PPC_ADV_DEBUG_REGS 392 static inline int __set_dabr(unsigned long dabr, unsigned long dabrx) 393 { 394 mtspr(SPRN_DAC1, dabr); 395 #ifdef CONFIG_PPC_47x 396 isync(); 397 #endif 398 return 0; 399 } 400 #elif defined(CONFIG_PPC_BOOK3S) 401 static inline int __set_dabr(unsigned long dabr, unsigned long dabrx) 402 { 403 mtspr(SPRN_DABR, dabr); 404 if (cpu_has_feature(CPU_FTR_DABRX)) 405 mtspr(SPRN_DABRX, dabrx); 406 return 0; 407 } 408 #else 409 static inline int __set_dabr(unsigned long dabr, unsigned long dabrx) 410 { 411 return -EINVAL; 412 } 413 #endif 414 415 static inline int set_dabr(struct arch_hw_breakpoint *brk) 416 { 417 unsigned long dabr, dabrx; 418 419 dabr = brk->address | (brk->type & HW_BRK_TYPE_DABR); 420 dabrx = ((brk->type >> 3) & 0x7); 421 422 if (ppc_md.set_dabr) 423 return ppc_md.set_dabr(dabr, dabrx); 424 425 return __set_dabr(dabr, dabrx); 426 } 427 428 static inline int set_dawr(struct arch_hw_breakpoint *brk) 429 { 430 unsigned long dawr, dawrx, mrd; 431 432 dawr = brk->address; 433 434 dawrx = (brk->type & (HW_BRK_TYPE_READ | HW_BRK_TYPE_WRITE)) \ 435 << (63 - 58); //* read/write bits */ 436 dawrx |= ((brk->type & (HW_BRK_TYPE_TRANSLATE)) >> 2) \ 437 << (63 - 59); //* translate */ 438 dawrx |= (brk->type & (HW_BRK_TYPE_PRIV_ALL)) \ 439 >> 3; //* PRIM bits */ 440 /* dawr length is stored in field MDR bits 48:53. Matches range in 441 doublewords (64 bits) baised by -1 eg. 0b000000=1DW and 442 0b111111=64DW. 443 brk->len is in bytes. 444 This aligns up to double word size, shifts and does the bias. 445 */ 446 mrd = ((brk->len + 7) >> 3) - 1; 447 dawrx |= (mrd & 0x3f) << (63 - 53); 448 449 if (ppc_md.set_dawr) 450 return ppc_md.set_dawr(dawr, dawrx); 451 mtspr(SPRN_DAWR, dawr); 452 mtspr(SPRN_DAWRX, dawrx); 453 return 0; 454 } 455 456 int set_breakpoint(struct arch_hw_breakpoint *brk) 457 { 458 __get_cpu_var(current_brk) = *brk; 459 460 if (cpu_has_feature(CPU_FTR_DAWR)) 461 return set_dawr(brk); 462 463 return set_dabr(brk); 464 } 465 466 #ifdef CONFIG_PPC64 467 DEFINE_PER_CPU(struct cpu_usage, cpu_usage_array); 468 #endif 469 470 static inline bool hw_brk_match(struct arch_hw_breakpoint *a, 471 struct arch_hw_breakpoint *b) 472 { 473 if (a->address != b->address) 474 return false; 475 if (a->type != b->type) 476 return false; 477 if (a->len != b->len) 478 return false; 479 return true; 480 } 481 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 482 static inline void tm_reclaim_task(struct task_struct *tsk) 483 { 484 /* We have to work out if we're switching from/to a task that's in the 485 * middle of a transaction. 486 * 487 * In switching we need to maintain a 2nd register state as 488 * oldtask->thread.ckpt_regs. We tm_reclaim(oldproc); this saves the 489 * checkpointed (tbegin) state in ckpt_regs and saves the transactional 490 * (current) FPRs into oldtask->thread.transact_fpr[]. 491 * 492 * We also context switch (save) TFHAR/TEXASR/TFIAR in here. 493 */ 494 struct thread_struct *thr = &tsk->thread; 495 496 if (!thr->regs) 497 return; 498 499 if (!MSR_TM_ACTIVE(thr->regs->msr)) 500 goto out_and_saveregs; 501 502 /* Stash the original thread MSR, as giveup_fpu et al will 503 * modify it. We hold onto it to see whether the task used 504 * FP & vector regs. 505 */ 506 thr->tm_orig_msr = thr->regs->msr; 507 508 TM_DEBUG("--- tm_reclaim on pid %d (NIP=%lx, " 509 "ccr=%lx, msr=%lx, trap=%lx)\n", 510 tsk->pid, thr->regs->nip, 511 thr->regs->ccr, thr->regs->msr, 512 thr->regs->trap); 513 514 tm_reclaim(thr, thr->regs->msr, TM_CAUSE_RESCHED); 515 516 TM_DEBUG("--- tm_reclaim on pid %d complete\n", 517 tsk->pid); 518 519 out_and_saveregs: 520 /* Always save the regs here, even if a transaction's not active. 521 * This context-switches a thread's TM info SPRs. We do it here to 522 * be consistent with the restore path (in recheckpoint) which 523 * cannot happen later in _switch(). 524 */ 525 tm_save_sprs(thr); 526 } 527 528 static inline void tm_recheckpoint_new_task(struct task_struct *new) 529 { 530 unsigned long msr; 531 532 if (!cpu_has_feature(CPU_FTR_TM)) 533 return; 534 535 /* Recheckpoint the registers of the thread we're about to switch to. 536 * 537 * If the task was using FP, we non-lazily reload both the original and 538 * the speculative FP register states. This is because the kernel 539 * doesn't see if/when a TM rollback occurs, so if we take an FP 540 * unavoidable later, we are unable to determine which set of FP regs 541 * need to be restored. 542 */ 543 if (!new->thread.regs) 544 return; 545 546 /* The TM SPRs are restored here, so that TEXASR.FS can be set 547 * before the trecheckpoint and no explosion occurs. 548 */ 549 tm_restore_sprs(&new->thread); 550 551 if (!MSR_TM_ACTIVE(new->thread.regs->msr)) 552 return; 553 msr = new->thread.tm_orig_msr; 554 /* Recheckpoint to restore original checkpointed register state. */ 555 TM_DEBUG("*** tm_recheckpoint of pid %d " 556 "(new->msr 0x%lx, new->origmsr 0x%lx)\n", 557 new->pid, new->thread.regs->msr, msr); 558 559 /* This loads the checkpointed FP/VEC state, if used */ 560 tm_recheckpoint(&new->thread, msr); 561 562 /* This loads the speculative FP/VEC state, if used */ 563 if (msr & MSR_FP) { 564 do_load_up_transact_fpu(&new->thread); 565 new->thread.regs->msr |= 566 (MSR_FP | new->thread.fpexc_mode); 567 } 568 #ifdef CONFIG_ALTIVEC 569 if (msr & MSR_VEC) { 570 do_load_up_transact_altivec(&new->thread); 571 new->thread.regs->msr |= MSR_VEC; 572 } 573 #endif 574 /* We may as well turn on VSX too since all the state is restored now */ 575 if (msr & MSR_VSX) 576 new->thread.regs->msr |= MSR_VSX; 577 578 TM_DEBUG("*** tm_recheckpoint of pid %d complete " 579 "(kernel msr 0x%lx)\n", 580 new->pid, mfmsr()); 581 } 582 583 static inline void __switch_to_tm(struct task_struct *prev) 584 { 585 if (cpu_has_feature(CPU_FTR_TM)) { 586 tm_enable(); 587 tm_reclaim_task(prev); 588 } 589 } 590 #else 591 #define tm_recheckpoint_new_task(new) 592 #define __switch_to_tm(prev) 593 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */ 594 595 struct task_struct *__switch_to(struct task_struct *prev, 596 struct task_struct *new) 597 { 598 struct thread_struct *new_thread, *old_thread; 599 unsigned long flags; 600 struct task_struct *last; 601 #ifdef CONFIG_PPC_BOOK3S_64 602 struct ppc64_tlb_batch *batch; 603 #endif 604 605 /* Back up the TAR across context switches. 606 * Note that the TAR is not available for use in the kernel. (To 607 * provide this, the TAR should be backed up/restored on exception 608 * entry/exit instead, and be in pt_regs. FIXME, this should be in 609 * pt_regs anyway (for debug).) 610 * Save the TAR here before we do treclaim/trecheckpoint as these 611 * will change the TAR. 612 */ 613 save_tar(&prev->thread); 614 615 __switch_to_tm(prev); 616 617 #ifdef CONFIG_SMP 618 /* avoid complexity of lazy save/restore of fpu 619 * by just saving it every time we switch out if 620 * this task used the fpu during the last quantum. 621 * 622 * If it tries to use the fpu again, it'll trap and 623 * reload its fp regs. So we don't have to do a restore 624 * every switch, just a save. 625 * -- Cort 626 */ 627 if (prev->thread.regs && (prev->thread.regs->msr & MSR_FP)) 628 giveup_fpu(prev); 629 #ifdef CONFIG_ALTIVEC 630 /* 631 * If the previous thread used altivec in the last quantum 632 * (thus changing altivec regs) then save them. 633 * We used to check the VRSAVE register but not all apps 634 * set it, so we don't rely on it now (and in fact we need 635 * to save & restore VSCR even if VRSAVE == 0). -- paulus 636 * 637 * On SMP we always save/restore altivec regs just to avoid the 638 * complexity of changing processors. 639 * -- Cort 640 */ 641 if (prev->thread.regs && (prev->thread.regs->msr & MSR_VEC)) 642 giveup_altivec(prev); 643 #endif /* CONFIG_ALTIVEC */ 644 #ifdef CONFIG_VSX 645 if (prev->thread.regs && (prev->thread.regs->msr & MSR_VSX)) 646 /* VMX and FPU registers are already save here */ 647 __giveup_vsx(prev); 648 #endif /* CONFIG_VSX */ 649 #ifdef CONFIG_SPE 650 /* 651 * If the previous thread used spe in the last quantum 652 * (thus changing spe regs) then save them. 653 * 654 * On SMP we always save/restore spe regs just to avoid the 655 * complexity of changing processors. 656 */ 657 if ((prev->thread.regs && (prev->thread.regs->msr & MSR_SPE))) 658 giveup_spe(prev); 659 #endif /* CONFIG_SPE */ 660 661 #else /* CONFIG_SMP */ 662 #ifdef CONFIG_ALTIVEC 663 /* Avoid the trap. On smp this this never happens since 664 * we don't set last_task_used_altivec -- Cort 665 */ 666 if (new->thread.regs && last_task_used_altivec == new) 667 new->thread.regs->msr |= MSR_VEC; 668 #endif /* CONFIG_ALTIVEC */ 669 #ifdef CONFIG_VSX 670 if (new->thread.regs && last_task_used_vsx == new) 671 new->thread.regs->msr |= MSR_VSX; 672 #endif /* CONFIG_VSX */ 673 #ifdef CONFIG_SPE 674 /* Avoid the trap. On smp this this never happens since 675 * we don't set last_task_used_spe 676 */ 677 if (new->thread.regs && last_task_used_spe == new) 678 new->thread.regs->msr |= MSR_SPE; 679 #endif /* CONFIG_SPE */ 680 681 #endif /* CONFIG_SMP */ 682 683 #ifdef CONFIG_PPC_ADV_DEBUG_REGS 684 switch_booke_debug_regs(&new->thread); 685 #else 686 /* 687 * For PPC_BOOK3S_64, we use the hw-breakpoint interfaces that would 688 * schedule DABR 689 */ 690 #ifndef CONFIG_HAVE_HW_BREAKPOINT 691 if (unlikely(hw_brk_match(&__get_cpu_var(current_brk), &new->thread.hw_brk))) 692 set_breakpoint(&new->thread.hw_brk); 693 #endif /* CONFIG_HAVE_HW_BREAKPOINT */ 694 #endif 695 696 697 new_thread = &new->thread; 698 old_thread = ¤t->thread; 699 700 #ifdef CONFIG_PPC64 701 /* 702 * Collect processor utilization data per process 703 */ 704 if (firmware_has_feature(FW_FEATURE_SPLPAR)) { 705 struct cpu_usage *cu = &__get_cpu_var(cpu_usage_array); 706 long unsigned start_tb, current_tb; 707 start_tb = old_thread->start_tb; 708 cu->current_tb = current_tb = mfspr(SPRN_PURR); 709 old_thread->accum_tb += (current_tb - start_tb); 710 new_thread->start_tb = current_tb; 711 } 712 #endif /* CONFIG_PPC64 */ 713 714 #ifdef CONFIG_PPC_BOOK3S_64 715 batch = &__get_cpu_var(ppc64_tlb_batch); 716 if (batch->active) { 717 current_thread_info()->local_flags |= _TLF_LAZY_MMU; 718 if (batch->index) 719 __flush_tlb_pending(batch); 720 batch->active = 0; 721 } 722 #endif /* CONFIG_PPC_BOOK3S_64 */ 723 724 local_irq_save(flags); 725 726 /* 727 * We can't take a PMU exception inside _switch() since there is a 728 * window where the kernel stack SLB and the kernel stack are out 729 * of sync. Hard disable here. 730 */ 731 hard_irq_disable(); 732 733 tm_recheckpoint_new_task(new); 734 735 last = _switch(old_thread, new_thread); 736 737 #ifdef CONFIG_PPC_BOOK3S_64 738 if (current_thread_info()->local_flags & _TLF_LAZY_MMU) { 739 current_thread_info()->local_flags &= ~_TLF_LAZY_MMU; 740 batch = &__get_cpu_var(ppc64_tlb_batch); 741 batch->active = 1; 742 } 743 #endif /* CONFIG_PPC_BOOK3S_64 */ 744 745 local_irq_restore(flags); 746 747 return last; 748 } 749 750 static int instructions_to_print = 16; 751 752 static void show_instructions(struct pt_regs *regs) 753 { 754 int i; 755 unsigned long pc = regs->nip - (instructions_to_print * 3 / 4 * 756 sizeof(int)); 757 758 printk("Instruction dump:"); 759 760 for (i = 0; i < instructions_to_print; i++) { 761 int instr; 762 763 if (!(i % 8)) 764 printk("\n"); 765 766 #if !defined(CONFIG_BOOKE) 767 /* If executing with the IMMU off, adjust pc rather 768 * than print XXXXXXXX. 769 */ 770 if (!(regs->msr & MSR_IR)) 771 pc = (unsigned long)phys_to_virt(pc); 772 #endif 773 774 /* We use __get_user here *only* to avoid an OOPS on a 775 * bad address because the pc *should* only be a 776 * kernel address. 777 */ 778 if (!__kernel_text_address(pc) || 779 __get_user(instr, (unsigned int __user *)pc)) { 780 printk(KERN_CONT "XXXXXXXX "); 781 } else { 782 if (regs->nip == pc) 783 printk(KERN_CONT "<%08x> ", instr); 784 else 785 printk(KERN_CONT "%08x ", instr); 786 } 787 788 pc += sizeof(int); 789 } 790 791 printk("\n"); 792 } 793 794 static struct regbit { 795 unsigned long bit; 796 const char *name; 797 } msr_bits[] = { 798 #if defined(CONFIG_PPC64) && !defined(CONFIG_BOOKE) 799 {MSR_SF, "SF"}, 800 {MSR_HV, "HV"}, 801 #endif 802 {MSR_VEC, "VEC"}, 803 {MSR_VSX, "VSX"}, 804 #ifdef CONFIG_BOOKE 805 {MSR_CE, "CE"}, 806 #endif 807 {MSR_EE, "EE"}, 808 {MSR_PR, "PR"}, 809 {MSR_FP, "FP"}, 810 {MSR_ME, "ME"}, 811 #ifdef CONFIG_BOOKE 812 {MSR_DE, "DE"}, 813 #else 814 {MSR_SE, "SE"}, 815 {MSR_BE, "BE"}, 816 #endif 817 {MSR_IR, "IR"}, 818 {MSR_DR, "DR"}, 819 {MSR_PMM, "PMM"}, 820 #ifndef CONFIG_BOOKE 821 {MSR_RI, "RI"}, 822 {MSR_LE, "LE"}, 823 #endif 824 {0, NULL} 825 }; 826 827 static void printbits(unsigned long val, struct regbit *bits) 828 { 829 const char *sep = ""; 830 831 printk("<"); 832 for (; bits->bit; ++bits) 833 if (val & bits->bit) { 834 printk("%s%s", sep, bits->name); 835 sep = ","; 836 } 837 printk(">"); 838 } 839 840 #ifdef CONFIG_PPC64 841 #define REG "%016lx" 842 #define REGS_PER_LINE 4 843 #define LAST_VOLATILE 13 844 #else 845 #define REG "%08lx" 846 #define REGS_PER_LINE 8 847 #define LAST_VOLATILE 12 848 #endif 849 850 void show_regs(struct pt_regs * regs) 851 { 852 int i, trap; 853 854 show_regs_print_info(KERN_DEFAULT); 855 856 printk("NIP: "REG" LR: "REG" CTR: "REG"\n", 857 regs->nip, regs->link, regs->ctr); 858 printk("REGS: %p TRAP: %04lx %s (%s)\n", 859 regs, regs->trap, print_tainted(), init_utsname()->release); 860 printk("MSR: "REG" ", regs->msr); 861 printbits(regs->msr, msr_bits); 862 printk(" CR: %08lx XER: %08lx\n", regs->ccr, regs->xer); 863 #ifdef CONFIG_PPC64 864 printk("SOFTE: %ld\n", regs->softe); 865 #endif 866 trap = TRAP(regs); 867 if ((regs->trap != 0xc00) && cpu_has_feature(CPU_FTR_CFAR)) 868 printk("CFAR: "REG"\n", regs->orig_gpr3); 869 if (trap == 0x300 || trap == 0x600) 870 #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE) 871 printk("DEAR: "REG", ESR: "REG"\n", regs->dar, regs->dsisr); 872 #else 873 printk("DAR: "REG", DSISR: %08lx\n", regs->dar, regs->dsisr); 874 #endif 875 876 for (i = 0; i < 32; i++) { 877 if ((i % REGS_PER_LINE) == 0) 878 printk("\nGPR%02d: ", i); 879 printk(REG " ", regs->gpr[i]); 880 if (i == LAST_VOLATILE && !FULL_REGS(regs)) 881 break; 882 } 883 printk("\n"); 884 #ifdef CONFIG_KALLSYMS 885 /* 886 * Lookup NIP late so we have the best change of getting the 887 * above info out without failing 888 */ 889 printk("NIP ["REG"] %pS\n", regs->nip, (void *)regs->nip); 890 printk("LR ["REG"] %pS\n", regs->link, (void *)regs->link); 891 #endif 892 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 893 printk("PACATMSCRATCH [%llx]\n", get_paca()->tm_scratch); 894 #endif 895 show_stack(current, (unsigned long *) regs->gpr[1]); 896 if (!user_mode(regs)) 897 show_instructions(regs); 898 } 899 900 void exit_thread(void) 901 { 902 discard_lazy_cpu_state(); 903 } 904 905 void flush_thread(void) 906 { 907 discard_lazy_cpu_state(); 908 909 #ifdef CONFIG_HAVE_HW_BREAKPOINT 910 flush_ptrace_hw_breakpoint(current); 911 #else /* CONFIG_HAVE_HW_BREAKPOINT */ 912 set_debug_reg_defaults(¤t->thread); 913 #endif /* CONFIG_HAVE_HW_BREAKPOINT */ 914 } 915 916 void 917 release_thread(struct task_struct *t) 918 { 919 } 920 921 /* 922 * this gets called so that we can store coprocessor state into memory and 923 * copy the current task into the new thread. 924 */ 925 int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) 926 { 927 flush_fp_to_thread(src); 928 flush_altivec_to_thread(src); 929 flush_vsx_to_thread(src); 930 flush_spe_to_thread(src); 931 932 *dst = *src; 933 934 clear_task_ebb(dst); 935 936 return 0; 937 } 938 939 /* 940 * Copy a thread.. 941 */ 942 extern unsigned long dscr_default; /* defined in arch/powerpc/kernel/sysfs.c */ 943 944 int copy_thread(unsigned long clone_flags, unsigned long usp, 945 unsigned long arg, struct task_struct *p) 946 { 947 struct pt_regs *childregs, *kregs; 948 extern void ret_from_fork(void); 949 extern void ret_from_kernel_thread(void); 950 void (*f)(void); 951 unsigned long sp = (unsigned long)task_stack_page(p) + THREAD_SIZE; 952 953 /* Copy registers */ 954 sp -= sizeof(struct pt_regs); 955 childregs = (struct pt_regs *) sp; 956 if (unlikely(p->flags & PF_KTHREAD)) { 957 struct thread_info *ti = (void *)task_stack_page(p); 958 memset(childregs, 0, sizeof(struct pt_regs)); 959 childregs->gpr[1] = sp + sizeof(struct pt_regs); 960 childregs->gpr[14] = usp; /* function */ 961 #ifdef CONFIG_PPC64 962 clear_tsk_thread_flag(p, TIF_32BIT); 963 childregs->softe = 1; 964 #endif 965 childregs->gpr[15] = arg; 966 p->thread.regs = NULL; /* no user register state */ 967 ti->flags |= _TIF_RESTOREALL; 968 f = ret_from_kernel_thread; 969 } else { 970 struct pt_regs *regs = current_pt_regs(); 971 CHECK_FULL_REGS(regs); 972 *childregs = *regs; 973 if (usp) 974 childregs->gpr[1] = usp; 975 p->thread.regs = childregs; 976 childregs->gpr[3] = 0; /* Result from fork() */ 977 if (clone_flags & CLONE_SETTLS) { 978 #ifdef CONFIG_PPC64 979 if (!is_32bit_task()) 980 childregs->gpr[13] = childregs->gpr[6]; 981 else 982 #endif 983 childregs->gpr[2] = childregs->gpr[6]; 984 } 985 986 f = ret_from_fork; 987 } 988 sp -= STACK_FRAME_OVERHEAD; 989 990 /* 991 * The way this works is that at some point in the future 992 * some task will call _switch to switch to the new task. 993 * That will pop off the stack frame created below and start 994 * the new task running at ret_from_fork. The new task will 995 * do some house keeping and then return from the fork or clone 996 * system call, using the stack frame created above. 997 */ 998 ((unsigned long *)sp)[0] = 0; 999 sp -= sizeof(struct pt_regs); 1000 kregs = (struct pt_regs *) sp; 1001 sp -= STACK_FRAME_OVERHEAD; 1002 p->thread.ksp = sp; 1003 p->thread.ksp_limit = (unsigned long)task_stack_page(p) + 1004 _ALIGN_UP(sizeof(struct thread_info), 16); 1005 1006 #ifdef CONFIG_HAVE_HW_BREAKPOINT 1007 p->thread.ptrace_bps[0] = NULL; 1008 #endif 1009 1010 #ifdef CONFIG_PPC_STD_MMU_64 1011 if (mmu_has_feature(MMU_FTR_SLB)) { 1012 unsigned long sp_vsid; 1013 unsigned long llp = mmu_psize_defs[mmu_linear_psize].sllp; 1014 1015 if (mmu_has_feature(MMU_FTR_1T_SEGMENT)) 1016 sp_vsid = get_kernel_vsid(sp, MMU_SEGSIZE_1T) 1017 << SLB_VSID_SHIFT_1T; 1018 else 1019 sp_vsid = get_kernel_vsid(sp, MMU_SEGSIZE_256M) 1020 << SLB_VSID_SHIFT; 1021 sp_vsid |= SLB_VSID_KERNEL | llp; 1022 p->thread.ksp_vsid = sp_vsid; 1023 } 1024 #endif /* CONFIG_PPC_STD_MMU_64 */ 1025 #ifdef CONFIG_PPC64 1026 if (cpu_has_feature(CPU_FTR_DSCR)) { 1027 p->thread.dscr_inherit = current->thread.dscr_inherit; 1028 p->thread.dscr = current->thread.dscr; 1029 } 1030 if (cpu_has_feature(CPU_FTR_HAS_PPR)) 1031 p->thread.ppr = INIT_PPR; 1032 #endif 1033 /* 1034 * The PPC64 ABI makes use of a TOC to contain function 1035 * pointers. The function (ret_from_except) is actually a pointer 1036 * to the TOC entry. The first entry is a pointer to the actual 1037 * function. 1038 */ 1039 #ifdef CONFIG_PPC64 1040 kregs->nip = *((unsigned long *)f); 1041 #else 1042 kregs->nip = (unsigned long)f; 1043 #endif 1044 return 0; 1045 } 1046 1047 /* 1048 * Set up a thread for executing a new program 1049 */ 1050 void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp) 1051 { 1052 #ifdef CONFIG_PPC64 1053 unsigned long load_addr = regs->gpr[2]; /* saved by ELF_PLAT_INIT */ 1054 #endif 1055 1056 /* 1057 * If we exec out of a kernel thread then thread.regs will not be 1058 * set. Do it now. 1059 */ 1060 if (!current->thread.regs) { 1061 struct pt_regs *regs = task_stack_page(current) + THREAD_SIZE; 1062 current->thread.regs = regs - 1; 1063 } 1064 1065 memset(regs->gpr, 0, sizeof(regs->gpr)); 1066 regs->ctr = 0; 1067 regs->link = 0; 1068 regs->xer = 0; 1069 regs->ccr = 0; 1070 regs->gpr[1] = sp; 1071 1072 /* 1073 * We have just cleared all the nonvolatile GPRs, so make 1074 * FULL_REGS(regs) return true. This is necessary to allow 1075 * ptrace to examine the thread immediately after exec. 1076 */ 1077 regs->trap &= ~1UL; 1078 1079 #ifdef CONFIG_PPC32 1080 regs->mq = 0; 1081 regs->nip = start; 1082 regs->msr = MSR_USER; 1083 #else 1084 if (!is_32bit_task()) { 1085 unsigned long entry, toc; 1086 1087 /* start is a relocated pointer to the function descriptor for 1088 * the elf _start routine. The first entry in the function 1089 * descriptor is the entry address of _start and the second 1090 * entry is the TOC value we need to use. 1091 */ 1092 __get_user(entry, (unsigned long __user *)start); 1093 __get_user(toc, (unsigned long __user *)start+1); 1094 1095 /* Check whether the e_entry function descriptor entries 1096 * need to be relocated before we can use them. 1097 */ 1098 if (load_addr != 0) { 1099 entry += load_addr; 1100 toc += load_addr; 1101 } 1102 regs->nip = entry; 1103 regs->gpr[2] = toc; 1104 regs->msr = MSR_USER64; 1105 } else { 1106 regs->nip = start; 1107 regs->gpr[2] = 0; 1108 regs->msr = MSR_USER32; 1109 } 1110 #endif 1111 discard_lazy_cpu_state(); 1112 #ifdef CONFIG_VSX 1113 current->thread.used_vsr = 0; 1114 #endif 1115 memset(current->thread.fpr, 0, sizeof(current->thread.fpr)); 1116 current->thread.fpscr.val = 0; 1117 #ifdef CONFIG_ALTIVEC 1118 memset(current->thread.vr, 0, sizeof(current->thread.vr)); 1119 memset(¤t->thread.vscr, 0, sizeof(current->thread.vscr)); 1120 current->thread.vscr.u[3] = 0x00010000; /* Java mode disabled */ 1121 current->thread.vrsave = 0; 1122 current->thread.used_vr = 0; 1123 #endif /* CONFIG_ALTIVEC */ 1124 #ifdef CONFIG_SPE 1125 memset(current->thread.evr, 0, sizeof(current->thread.evr)); 1126 current->thread.acc = 0; 1127 current->thread.spefscr = 0; 1128 current->thread.used_spe = 0; 1129 #endif /* CONFIG_SPE */ 1130 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 1131 if (cpu_has_feature(CPU_FTR_TM)) 1132 regs->msr |= MSR_TM; 1133 current->thread.tm_tfhar = 0; 1134 current->thread.tm_texasr = 0; 1135 current->thread.tm_tfiar = 0; 1136 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */ 1137 } 1138 1139 #define PR_FP_ALL_EXCEPT (PR_FP_EXC_DIV | PR_FP_EXC_OVF | PR_FP_EXC_UND \ 1140 | PR_FP_EXC_RES | PR_FP_EXC_INV) 1141 1142 int set_fpexc_mode(struct task_struct *tsk, unsigned int val) 1143 { 1144 struct pt_regs *regs = tsk->thread.regs; 1145 1146 /* This is a bit hairy. If we are an SPE enabled processor 1147 * (have embedded fp) we store the IEEE exception enable flags in 1148 * fpexc_mode. fpexc_mode is also used for setting FP exception 1149 * mode (asyn, precise, disabled) for 'Classic' FP. */ 1150 if (val & PR_FP_EXC_SW_ENABLE) { 1151 #ifdef CONFIG_SPE 1152 if (cpu_has_feature(CPU_FTR_SPE)) { 1153 tsk->thread.fpexc_mode = val & 1154 (PR_FP_EXC_SW_ENABLE | PR_FP_ALL_EXCEPT); 1155 return 0; 1156 } else { 1157 return -EINVAL; 1158 } 1159 #else 1160 return -EINVAL; 1161 #endif 1162 } 1163 1164 /* on a CONFIG_SPE this does not hurt us. The bits that 1165 * __pack_fe01 use do not overlap with bits used for 1166 * PR_FP_EXC_SW_ENABLE. Additionally, the MSR[FE0,FE1] bits 1167 * on CONFIG_SPE implementations are reserved so writing to 1168 * them does not change anything */ 1169 if (val > PR_FP_EXC_PRECISE) 1170 return -EINVAL; 1171 tsk->thread.fpexc_mode = __pack_fe01(val); 1172 if (regs != NULL && (regs->msr & MSR_FP) != 0) 1173 regs->msr = (regs->msr & ~(MSR_FE0|MSR_FE1)) 1174 | tsk->thread.fpexc_mode; 1175 return 0; 1176 } 1177 1178 int get_fpexc_mode(struct task_struct *tsk, unsigned long adr) 1179 { 1180 unsigned int val; 1181 1182 if (tsk->thread.fpexc_mode & PR_FP_EXC_SW_ENABLE) 1183 #ifdef CONFIG_SPE 1184 if (cpu_has_feature(CPU_FTR_SPE)) 1185 val = tsk->thread.fpexc_mode; 1186 else 1187 return -EINVAL; 1188 #else 1189 return -EINVAL; 1190 #endif 1191 else 1192 val = __unpack_fe01(tsk->thread.fpexc_mode); 1193 return put_user(val, (unsigned int __user *) adr); 1194 } 1195 1196 int set_endian(struct task_struct *tsk, unsigned int val) 1197 { 1198 struct pt_regs *regs = tsk->thread.regs; 1199 1200 if ((val == PR_ENDIAN_LITTLE && !cpu_has_feature(CPU_FTR_REAL_LE)) || 1201 (val == PR_ENDIAN_PPC_LITTLE && !cpu_has_feature(CPU_FTR_PPC_LE))) 1202 return -EINVAL; 1203 1204 if (regs == NULL) 1205 return -EINVAL; 1206 1207 if (val == PR_ENDIAN_BIG) 1208 regs->msr &= ~MSR_LE; 1209 else if (val == PR_ENDIAN_LITTLE || val == PR_ENDIAN_PPC_LITTLE) 1210 regs->msr |= MSR_LE; 1211 else 1212 return -EINVAL; 1213 1214 return 0; 1215 } 1216 1217 int get_endian(struct task_struct *tsk, unsigned long adr) 1218 { 1219 struct pt_regs *regs = tsk->thread.regs; 1220 unsigned int val; 1221 1222 if (!cpu_has_feature(CPU_FTR_PPC_LE) && 1223 !cpu_has_feature(CPU_FTR_REAL_LE)) 1224 return -EINVAL; 1225 1226 if (regs == NULL) 1227 return -EINVAL; 1228 1229 if (regs->msr & MSR_LE) { 1230 if (cpu_has_feature(CPU_FTR_REAL_LE)) 1231 val = PR_ENDIAN_LITTLE; 1232 else 1233 val = PR_ENDIAN_PPC_LITTLE; 1234 } else 1235 val = PR_ENDIAN_BIG; 1236 1237 return put_user(val, (unsigned int __user *)adr); 1238 } 1239 1240 int set_unalign_ctl(struct task_struct *tsk, unsigned int val) 1241 { 1242 tsk->thread.align_ctl = val; 1243 return 0; 1244 } 1245 1246 int get_unalign_ctl(struct task_struct *tsk, unsigned long adr) 1247 { 1248 return put_user(tsk->thread.align_ctl, (unsigned int __user *)adr); 1249 } 1250 1251 static inline int valid_irq_stack(unsigned long sp, struct task_struct *p, 1252 unsigned long nbytes) 1253 { 1254 unsigned long stack_page; 1255 unsigned long cpu = task_cpu(p); 1256 1257 /* 1258 * Avoid crashing if the stack has overflowed and corrupted 1259 * task_cpu(p), which is in the thread_info struct. 1260 */ 1261 if (cpu < NR_CPUS && cpu_possible(cpu)) { 1262 stack_page = (unsigned long) hardirq_ctx[cpu]; 1263 if (sp >= stack_page + sizeof(struct thread_struct) 1264 && sp <= stack_page + THREAD_SIZE - nbytes) 1265 return 1; 1266 1267 stack_page = (unsigned long) softirq_ctx[cpu]; 1268 if (sp >= stack_page + sizeof(struct thread_struct) 1269 && sp <= stack_page + THREAD_SIZE - nbytes) 1270 return 1; 1271 } 1272 return 0; 1273 } 1274 1275 int validate_sp(unsigned long sp, struct task_struct *p, 1276 unsigned long nbytes) 1277 { 1278 unsigned long stack_page = (unsigned long)task_stack_page(p); 1279 1280 if (sp >= stack_page + sizeof(struct thread_struct) 1281 && sp <= stack_page + THREAD_SIZE - nbytes) 1282 return 1; 1283 1284 return valid_irq_stack(sp, p, nbytes); 1285 } 1286 1287 EXPORT_SYMBOL(validate_sp); 1288 1289 unsigned long get_wchan(struct task_struct *p) 1290 { 1291 unsigned long ip, sp; 1292 int count = 0; 1293 1294 if (!p || p == current || p->state == TASK_RUNNING) 1295 return 0; 1296 1297 sp = p->thread.ksp; 1298 if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD)) 1299 return 0; 1300 1301 do { 1302 sp = *(unsigned long *)sp; 1303 if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD)) 1304 return 0; 1305 if (count > 0) { 1306 ip = ((unsigned long *)sp)[STACK_FRAME_LR_SAVE]; 1307 if (!in_sched_functions(ip)) 1308 return ip; 1309 } 1310 } while (count++ < 16); 1311 return 0; 1312 } 1313 1314 static int kstack_depth_to_print = CONFIG_PRINT_STACK_DEPTH; 1315 1316 void show_stack(struct task_struct *tsk, unsigned long *stack) 1317 { 1318 unsigned long sp, ip, lr, newsp; 1319 int count = 0; 1320 int firstframe = 1; 1321 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1322 int curr_frame = current->curr_ret_stack; 1323 extern void return_to_handler(void); 1324 unsigned long rth = (unsigned long)return_to_handler; 1325 unsigned long mrth = -1; 1326 #ifdef CONFIG_PPC64 1327 extern void mod_return_to_handler(void); 1328 rth = *(unsigned long *)rth; 1329 mrth = (unsigned long)mod_return_to_handler; 1330 mrth = *(unsigned long *)mrth; 1331 #endif 1332 #endif 1333 1334 sp = (unsigned long) stack; 1335 if (tsk == NULL) 1336 tsk = current; 1337 if (sp == 0) { 1338 if (tsk == current) 1339 asm("mr %0,1" : "=r" (sp)); 1340 else 1341 sp = tsk->thread.ksp; 1342 } 1343 1344 lr = 0; 1345 printk("Call Trace:\n"); 1346 do { 1347 if (!validate_sp(sp, tsk, STACK_FRAME_OVERHEAD)) 1348 return; 1349 1350 stack = (unsigned long *) sp; 1351 newsp = stack[0]; 1352 ip = stack[STACK_FRAME_LR_SAVE]; 1353 if (!firstframe || ip != lr) { 1354 printk("["REG"] ["REG"] %pS", sp, ip, (void *)ip); 1355 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1356 if ((ip == rth || ip == mrth) && curr_frame >= 0) { 1357 printk(" (%pS)", 1358 (void *)current->ret_stack[curr_frame].ret); 1359 curr_frame--; 1360 } 1361 #endif 1362 if (firstframe) 1363 printk(" (unreliable)"); 1364 printk("\n"); 1365 } 1366 firstframe = 0; 1367 1368 /* 1369 * See if this is an exception frame. 1370 * We look for the "regshere" marker in the current frame. 1371 */ 1372 if (validate_sp(sp, tsk, STACK_INT_FRAME_SIZE) 1373 && stack[STACK_FRAME_MARKER] == STACK_FRAME_REGS_MARKER) { 1374 struct pt_regs *regs = (struct pt_regs *) 1375 (sp + STACK_FRAME_OVERHEAD); 1376 lr = regs->link; 1377 printk("--- Exception: %lx at %pS\n LR = %pS\n", 1378 regs->trap, (void *)regs->nip, (void *)lr); 1379 firstframe = 1; 1380 } 1381 1382 sp = newsp; 1383 } while (count++ < kstack_depth_to_print); 1384 } 1385 1386 #ifdef CONFIG_PPC64 1387 /* Called with hard IRQs off */ 1388 void notrace __ppc64_runlatch_on(void) 1389 { 1390 struct thread_info *ti = current_thread_info(); 1391 unsigned long ctrl; 1392 1393 ctrl = mfspr(SPRN_CTRLF); 1394 ctrl |= CTRL_RUNLATCH; 1395 mtspr(SPRN_CTRLT, ctrl); 1396 1397 ti->local_flags |= _TLF_RUNLATCH; 1398 } 1399 1400 /* Called with hard IRQs off */ 1401 void notrace __ppc64_runlatch_off(void) 1402 { 1403 struct thread_info *ti = current_thread_info(); 1404 unsigned long ctrl; 1405 1406 ti->local_flags &= ~_TLF_RUNLATCH; 1407 1408 ctrl = mfspr(SPRN_CTRLF); 1409 ctrl &= ~CTRL_RUNLATCH; 1410 mtspr(SPRN_CTRLT, ctrl); 1411 } 1412 #endif /* CONFIG_PPC64 */ 1413 1414 unsigned long arch_align_stack(unsigned long sp) 1415 { 1416 if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) 1417 sp -= get_random_int() & ~PAGE_MASK; 1418 return sp & ~0xf; 1419 } 1420 1421 static inline unsigned long brk_rnd(void) 1422 { 1423 unsigned long rnd = 0; 1424 1425 /* 8MB for 32bit, 1GB for 64bit */ 1426 if (is_32bit_task()) 1427 rnd = (long)(get_random_int() % (1<<(23-PAGE_SHIFT))); 1428 else 1429 rnd = (long)(get_random_int() % (1<<(30-PAGE_SHIFT))); 1430 1431 return rnd << PAGE_SHIFT; 1432 } 1433 1434 unsigned long arch_randomize_brk(struct mm_struct *mm) 1435 { 1436 unsigned long base = mm->brk; 1437 unsigned long ret; 1438 1439 #ifdef CONFIG_PPC_STD_MMU_64 1440 /* 1441 * If we are using 1TB segments and we are allowed to randomise 1442 * the heap, we can put it above 1TB so it is backed by a 1TB 1443 * segment. Otherwise the heap will be in the bottom 1TB 1444 * which always uses 256MB segments and this may result in a 1445 * performance penalty. 1446 */ 1447 if (!is_32bit_task() && (mmu_highuser_ssize == MMU_SEGSIZE_1T)) 1448 base = max_t(unsigned long, mm->brk, 1UL << SID_SHIFT_1T); 1449 #endif 1450 1451 ret = PAGE_ALIGN(base + brk_rnd()); 1452 1453 if (ret < mm->brk) 1454 return mm->brk; 1455 1456 return ret; 1457 } 1458 1459 unsigned long randomize_et_dyn(unsigned long base) 1460 { 1461 unsigned long ret = PAGE_ALIGN(base + brk_rnd()); 1462 1463 if (ret < base) 1464 return base; 1465 1466 return ret; 1467 } 1468