arch/powerpc/kernel/process.c

   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/prctl.h>
  29 #include <linux/init_task.h>
  30 #include <linux/export.h>
  31 #include <linux/kallsyms.h>
  32 #include <linux/mqueue.h>
  33 #include <linux/hardirq.h>
  34 #include <linux/utsname.h>
  35 #include <linux/ftrace.h>
  36 #include <linux/kernel_stat.h>
  37 #include <linux/personality.h>
  38 #include <linux/random.h>
  39 #include <linux/hw_breakpoint.h>
  40 #include <linux/uaccess.h>
  41 #include <linux/elf-randomize.h>
  42
  43 #include <asm/pgtable.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 <asm/code-patching.h>
  59 #include <asm/exec.h>
  60 #include <asm/livepatch.h>
  61 #include <asm/cpu_has_feature.h>
  62 #include <asm/asm-prototypes.h>
  63
  64 #include <linux/kprobes.h>
  65 #include <linux/kdebug.h>
  66
  67 /* Transactional Memory debug */
  68 #ifdef TM_DEBUG_SW
  69 #define TM_DEBUG(x...) printk(KERN_INFO x)
  70 #else
  71 #define TM_DEBUG(x...) do { } while(0)
  72 #endif
  73
  74 extern unsigned long _get_SP(void);
  75
  76 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
  77 static void check_if_tm_restore_required(struct task_struct *tsk)
  78 {
  79         /*
  80          * If we are saving the current thread's registers, and the
  81          * thread is in a transactional state, set the TIF_RESTORE_TM
  82          * bit so that we know to restore the registers before
  83          * returning to userspace.
  84          */
  85         if (tsk == current && tsk->thread.regs &&
  86             MSR_TM_ACTIVE(tsk->thread.regs->msr) &&
  87             !test_thread_flag(TIF_RESTORE_TM)) {
  88                 tsk->thread.ckpt_regs.msr = tsk->thread.regs->msr;
  89                 set_thread_flag(TIF_RESTORE_TM);
  90         }
  91 }
  92
  93 static inline bool msr_tm_active(unsigned long msr)
  94 {
  95         return MSR_TM_ACTIVE(msr);
  96 }
  97 #else
  98 static inline bool msr_tm_active(unsigned long msr) { return false; }
  99 static inline void check_if_tm_restore_required(struct task_struct *tsk) { }
 100 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
 101
 102 bool strict_msr_control;
 103 EXPORT_SYMBOL(strict_msr_control);
 104
 105 static int __init enable_strict_msr_control(char *str)
 106 {
 107         strict_msr_control = true;
 108         pr_info("Enabling strict facility control\n");
 109
 110         return 0;
 111 }
 112 early_param("ppc_strict_facility_enable", enable_strict_msr_control);
 113
 114 unsigned long msr_check_and_set(unsigned long bits)
 115 {
 116         unsigned long oldmsr = mfmsr();
 117         unsigned long newmsr;
 118
 119         newmsr = oldmsr | bits;
 120
 121 #ifdef CONFIG_VSX
 122         if (cpu_has_feature(CPU_FTR_VSX) && (bits & MSR_FP))
 123                 newmsr |= MSR_VSX;
 124 #endif
 125
 126         if (oldmsr != newmsr)
 127                 mtmsr_isync(newmsr);
 128
 129         return newmsr;
 130 }
 131
 132 void __msr_check_and_clear(unsigned long bits)
 133 {
 134         unsigned long oldmsr = mfmsr();
 135         unsigned long newmsr;
 136
 137         newmsr = oldmsr & ~bits;
 138
 139 #ifdef CONFIG_VSX
 140         if (cpu_has_feature(CPU_FTR_VSX) && (bits & MSR_FP))
 141                 newmsr &= ~MSR_VSX;
 142 #endif
 143
 144         if (oldmsr != newmsr)
 145                 mtmsr_isync(newmsr);
 146 }
 147 EXPORT_SYMBOL(__msr_check_and_clear);
 148
 149 #ifdef CONFIG_PPC_FPU
 150 void __giveup_fpu(struct task_struct *tsk)
 151 {
 152         unsigned long msr;
 153
 154         save_fpu(tsk);
 155         msr = tsk->thread.regs->msr;
 156         msr &= ~MSR_FP;
 157 #ifdef CONFIG_VSX
 158         if (cpu_has_feature(CPU_FTR_VSX))
 159                 msr &= ~MSR_VSX;
 160 #endif
 161         tsk->thread.regs->msr = msr;
 162 }
 163
 164 void giveup_fpu(struct task_struct *tsk)
 165 {
 166         check_if_tm_restore_required(tsk);
 167
 168         msr_check_and_set(MSR_FP);
 169         __giveup_fpu(tsk);
 170         msr_check_and_clear(MSR_FP);
 171 }
 172 EXPORT_SYMBOL(giveup_fpu);
 173
 174 /*
 175  * Make sure the floating-point register state in the
 176  * the thread_struct is up to date for task tsk.
 177  */
 178 void flush_fp_to_thread(struct task_struct *tsk)
 179 {
 180         if (tsk->thread.regs) {
 181                 /*
 182                  * We need to disable preemption here because if we didn't,
 183                  * another process could get scheduled after the regs->msr
 184                  * test but before we have finished saving the FP registers
 185                  * to the thread_struct.  That process could take over the
 186                  * FPU, and then when we get scheduled again we would store
 187                  * bogus values for the remaining FP registers.
 188                  */
 189                 preempt_disable();
 190                 if (tsk->thread.regs->msr & MSR_FP) {
 191                         /*
 192                          * This should only ever be called for current or
 193                          * for a stopped child process.  Since we save away
 194                          * the FP register state on context switch,
 195                          * there is something wrong if a stopped child appears
 196                          * to still have its FP state in the CPU registers.
 197                          */
 198                         BUG_ON(tsk != current);
 199                         giveup_fpu(tsk);
 200                 }
 201                 preempt_enable();
 202         }
 203 }
 204 EXPORT_SYMBOL_GPL(flush_fp_to_thread);
 205
 206 void enable_kernel_fp(void)
 207 {
 208         unsigned long cpumsr;
 209
 210         WARN_ON(preemptible());
 211
 212         cpumsr = msr_check_and_set(MSR_FP);
 213
 214         if (current->thread.regs && (current->thread.regs->msr & MSR_FP)) {
 215                 check_if_tm_restore_required(current);
 216                 /*
 217                  * If a thread has already been reclaimed then the
 218                  * checkpointed registers are on the CPU but have definitely
 219                  * been saved by the reclaim code. Don't need to and *cannot*
 220                  * giveup as this would save  to the 'live' structure not the
 221                  * checkpointed structure.
 222                  */
 223                 if(!msr_tm_active(cpumsr) && msr_tm_active(current->thread.regs->msr))
 224                         return;
 225                 __giveup_fpu(current);
 226         }
 227 }
 228 EXPORT_SYMBOL(enable_kernel_fp);
 229
 230 static int restore_fp(struct task_struct *tsk) {
 231         if (tsk->thread.load_fp || msr_tm_active(tsk->thread.regs->msr)) {
 232                 load_fp_state(&current->thread.fp_state);
 233                 current->thread.load_fp++;
 234                 return 1;
 235         }
 236         return 0;
 237 }
 238 #else
 239 static int restore_fp(struct task_struct *tsk) { return 0; }
 240 #endif /* CONFIG_PPC_FPU */
 241
 242 #ifdef CONFIG_ALTIVEC
 243 #define loadvec(thr) ((thr).load_vec)
 244
 245 static void __giveup_altivec(struct task_struct *tsk)
 246 {
 247         unsigned long msr;
 248
 249         save_altivec(tsk);
 250         msr = tsk->thread.regs->msr;
 251         msr &= ~MSR_VEC;
 252 #ifdef CONFIG_VSX
 253         if (cpu_has_feature(CPU_FTR_VSX))
 254                 msr &= ~MSR_VSX;
 255 #endif
 256         tsk->thread.regs->msr = msr;
 257 }
 258
 259 void giveup_altivec(struct task_struct *tsk)
 260 {
 261         check_if_tm_restore_required(tsk);
 262
 263         msr_check_and_set(MSR_VEC);
 264         __giveup_altivec(tsk);
 265         msr_check_and_clear(MSR_VEC);
 266 }
 267 EXPORT_SYMBOL(giveup_altivec);
 268
 269 void enable_kernel_altivec(void)
 270 {
 271         unsigned long cpumsr;
 272
 273         WARN_ON(preemptible());
 274
 275         cpumsr = msr_check_and_set(MSR_VEC);
 276
 277         if (current->thread.regs && (current->thread.regs->msr & MSR_VEC)) {
 278                 check_if_tm_restore_required(current);
 279                 /*
 280                  * If a thread has already been reclaimed then the
 281                  * checkpointed registers are on the CPU but have definitely
 282                  * been saved by the reclaim code. Don't need to and *cannot*
 283                  * giveup as this would save  to the 'live' structure not the
 284                  * checkpointed structure.
 285                  */
 286                 if(!msr_tm_active(cpumsr) && msr_tm_active(current->thread.regs->msr))
 287                         return;
 288                 __giveup_altivec(current);
 289         }
 290 }
 291 EXPORT_SYMBOL(enable_kernel_altivec);
 292
 293 /*
 294  * Make sure the VMX/Altivec register state in the
 295  * the thread_struct is up to date for task tsk.
 296  */
 297 void flush_altivec_to_thread(struct task_struct *tsk)
 298 {
 299         if (tsk->thread.regs) {
 300                 preempt_disable();
 301                 if (tsk->thread.regs->msr & MSR_VEC) {
 302                         BUG_ON(tsk != current);
 303                         giveup_altivec(tsk);
 304                 }
 305                 preempt_enable();
 306         }
 307 }
 308 EXPORT_SYMBOL_GPL(flush_altivec_to_thread);
 309
 310 static int restore_altivec(struct task_struct *tsk)
 311 {
 312         if (cpu_has_feature(CPU_FTR_ALTIVEC) &&
 313                 (tsk->thread.load_vec || msr_tm_active(tsk->thread.regs->msr))) {
 314                 load_vr_state(&tsk->thread.vr_state);
 315                 tsk->thread.used_vr = 1;
 316                 tsk->thread.load_vec++;
 317
 318                 return 1;
 319         }
 320         return 0;
 321 }
 322 #else
 323 #define loadvec(thr) 0
 324 static inline int restore_altivec(struct task_struct *tsk) { return 0; }
 325 #endif /* CONFIG_ALTIVEC */
 326
 327 #ifdef CONFIG_VSX
 328 static void __giveup_vsx(struct task_struct *tsk)
 329 {
 330         if (tsk->thread.regs->msr & MSR_FP)
 331                 __giveup_fpu(tsk);
 332         if (tsk->thread.regs->msr & MSR_VEC)
 333                 __giveup_altivec(tsk);
 334         tsk->thread.regs->msr &= ~MSR_VSX;
 335 }
 336
 337 static void giveup_vsx(struct task_struct *tsk)
 338 {
 339         check_if_tm_restore_required(tsk);
 340
 341         msr_check_and_set(MSR_FP|MSR_VEC|MSR_VSX);
 342         __giveup_vsx(tsk);
 343         msr_check_and_clear(MSR_FP|MSR_VEC|MSR_VSX);
 344 }
 345
 346 static void save_vsx(struct task_struct *tsk)
 347 {
 348         if (tsk->thread.regs->msr & MSR_FP)
 349                 save_fpu(tsk);
 350         if (tsk->thread.regs->msr & MSR_VEC)
 351                 save_altivec(tsk);
 352 }
 353
 354 void enable_kernel_vsx(void)
 355 {
 356         unsigned long cpumsr;
 357
 358         WARN_ON(preemptible());
 359
 360         cpumsr = msr_check_and_set(MSR_FP|MSR_VEC|MSR_VSX);
 361
 362         if (current->thread.regs && (current->thread.regs->msr & MSR_VSX)) {
 363                 check_if_tm_restore_required(current);
 364                 /*
 365                  * If a thread has already been reclaimed then the
 366                  * checkpointed registers are on the CPU but have definitely
 367                  * been saved by the reclaim code. Don't need to and *cannot*
 368                  * giveup as this would save  to the 'live' structure not the
 369                  * checkpointed structure.
 370                  */
 371                 if(!msr_tm_active(cpumsr) && msr_tm_active(current->thread.regs->msr))
 372                         return;
 373                 if (current->thread.regs->msr & MSR_FP)
 374                         __giveup_fpu(current);
 375                 if (current->thread.regs->msr & MSR_VEC)
 376                         __giveup_altivec(current);
 377                 __giveup_vsx(current);
 378         }
 379 }
 380 EXPORT_SYMBOL(enable_kernel_vsx);
 381
 382 void flush_vsx_to_thread(struct task_struct *tsk)
 383 {
 384         if (tsk->thread.regs) {
 385                 preempt_disable();
 386                 if (tsk->thread.regs->msr & MSR_VSX) {
 387                         BUG_ON(tsk != current);
 388                         giveup_vsx(tsk);
 389                 }
 390                 preempt_enable();
 391         }
 392 }
 393 EXPORT_SYMBOL_GPL(flush_vsx_to_thread);
 394
 395 static int restore_vsx(struct task_struct *tsk)
 396 {
 397         if (cpu_has_feature(CPU_FTR_VSX)) {
 398                 tsk->thread.used_vsr = 1;
 399                 return 1;
 400         }
 401
 402         return 0;
 403 }
 404 #else
 405 static inline int restore_vsx(struct task_struct *tsk) { return 0; }
 406 static inline void save_vsx(struct task_struct *tsk) { }
 407 #endif /* CONFIG_VSX */
 408
 409 #ifdef CONFIG_SPE
 410 void giveup_spe(struct task_struct *tsk)
 411 {
 412         check_if_tm_restore_required(tsk);
 413
 414         msr_check_and_set(MSR_SPE);
 415         __giveup_spe(tsk);
 416         msr_check_and_clear(MSR_SPE);
 417 }
 418 EXPORT_SYMBOL(giveup_spe);
 419
 420 void enable_kernel_spe(void)
 421 {
 422         WARN_ON(preemptible());
 423
 424         msr_check_and_set(MSR_SPE);
 425
 426         if (current->thread.regs && (current->thread.regs->msr & MSR_SPE)) {
 427                 check_if_tm_restore_required(current);
 428                 __giveup_spe(current);
 429         }
 430 }
 431 EXPORT_SYMBOL(enable_kernel_spe);
 432
 433 void flush_spe_to_thread(struct task_struct *tsk)
 434 {
 435         if (tsk->thread.regs) {
 436                 preempt_disable();
 437                 if (tsk->thread.regs->msr & MSR_SPE) {
 438                         BUG_ON(tsk != current);
 439                         tsk->thread.spefscr = mfspr(SPRN_SPEFSCR);
 440                         giveup_spe(tsk);
 441                 }
 442                 preempt_enable();
 443         }
 444 }
 445 #endif /* CONFIG_SPE */
 446
 447 static unsigned long msr_all_available;
 448
 449 static int __init init_msr_all_available(void)
 450 {
 451 #ifdef CONFIG_PPC_FPU
 452         msr_all_available |= MSR_FP;
 453 #endif
 454 #ifdef CONFIG_ALTIVEC
 455         if (cpu_has_feature(CPU_FTR_ALTIVEC))
 456                 msr_all_available |= MSR_VEC;
 457 #endif
 458 #ifdef CONFIG_VSX
 459         if (cpu_has_feature(CPU_FTR_VSX))
 460                 msr_all_available |= MSR_VSX;
 461 #endif
 462 #ifdef CONFIG_SPE
 463         if (cpu_has_feature(CPU_FTR_SPE))
 464                 msr_all_available |= MSR_SPE;
 465 #endif
 466
 467         return 0;
 468 }
 469 early_initcall(init_msr_all_available);
 470
 471 void giveup_all(struct task_struct *tsk)
 472 {
 473         unsigned long usermsr;
 474
 475         if (!tsk->thread.regs)
 476                 return;
 477
 478         usermsr = tsk->thread.regs->msr;
 479
 480         if ((usermsr & msr_all_available) == 0)
 481                 return;
 482
 483         msr_check_and_set(msr_all_available);
 484         check_if_tm_restore_required(tsk);
 485
 486 #ifdef CONFIG_PPC_FPU
 487         if (usermsr & MSR_FP)
 488                 __giveup_fpu(tsk);
 489 #endif
 490 #ifdef CONFIG_ALTIVEC
 491         if (usermsr & MSR_VEC)
 492                 __giveup_altivec(tsk);
 493 #endif
 494 #ifdef CONFIG_VSX
 495         if (usermsr & MSR_VSX)
 496                 __giveup_vsx(tsk);
 497 #endif
 498 #ifdef CONFIG_SPE
 499         if (usermsr & MSR_SPE)
 500                 __giveup_spe(tsk);
 501 #endif
 502
 503         msr_check_and_clear(msr_all_available);
 504 }
 505 EXPORT_SYMBOL(giveup_all);
 506
 507 void restore_math(struct pt_regs *regs)
 508 {
 509         unsigned long msr;
 510
 511         if (!msr_tm_active(regs->msr) &&
 512                 !current->thread.load_fp && !loadvec(current->thread))
 513                 return;
 514
 515         msr = regs->msr;
 516         msr_check_and_set(msr_all_available);
 517
 518         /*
 519          * Only reload if the bit is not set in the user MSR, the bit BEING set
 520          * indicates that the registers are hot
 521          */
 522         if ((!(msr & MSR_FP)) && restore_fp(current))
 523                 msr |= MSR_FP | current->thread.fpexc_mode;
 524
 525         if ((!(msr & MSR_VEC)) && restore_altivec(current))
 526                 msr |= MSR_VEC;
 527
 528         if ((msr & (MSR_FP | MSR_VEC)) == (MSR_FP | MSR_VEC) &&
 529                         restore_vsx(current)) {
 530                 msr |= MSR_VSX;
 531         }
 532
 533         msr_check_and_clear(msr_all_available);
 534
 535         regs->msr = msr;
 536 }
 537
 538 void save_all(struct task_struct *tsk)
 539 {
 540         unsigned long usermsr;
 541
 542         if (!tsk->thread.regs)
 543                 return;
 544
 545         usermsr = tsk->thread.regs->msr;
 546
 547         if ((usermsr & msr_all_available) == 0)
 548                 return;
 549
 550         msr_check_and_set(msr_all_available);
 551
 552         /*
 553          * Saving the way the register space is in hardware, save_vsx boils
 554          * down to a save_fpu() and save_altivec()
 555          */
 556         if (usermsr & MSR_VSX) {
 557                 save_vsx(tsk);
 558         } else {
 559                 if (usermsr & MSR_FP)
 560                         save_fpu(tsk);
 561
 562                 if (usermsr & MSR_VEC)
 563                         save_altivec(tsk);
 564         }
 565
 566         if (usermsr & MSR_SPE)
 567                 __giveup_spe(tsk);
 568
 569         msr_check_and_clear(msr_all_available);
 570 }
 571
 572 void flush_all_to_thread(struct task_struct *tsk)
 573 {
 574         if (tsk->thread.regs) {
 575                 preempt_disable();
 576                 BUG_ON(tsk != current);
 577                 save_all(tsk);
 578
 579 #ifdef CONFIG_SPE
 580                 if (tsk->thread.regs->msr & MSR_SPE)
 581                         tsk->thread.spefscr = mfspr(SPRN_SPEFSCR);
 582 #endif
 583
 584                 preempt_enable();
 585         }
 586 }
 587 EXPORT_SYMBOL(flush_all_to_thread);
 588
 589 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
 590 void do_send_trap(struct pt_regs *regs, unsigned long address,
 591                   unsigned long error_code, int signal_code, int breakpt)
 592 {
 593         siginfo_t info;
 594
 595         current->thread.trap_nr = signal_code;
 596         if (notify_die(DIE_DABR_MATCH, "dabr_match", regs, error_code,
 597                         11, SIGSEGV) == NOTIFY_STOP)
 598                 return;
 599
 600         /* Deliver the signal to userspace */
 601         info.si_signo = SIGTRAP;
 602         info.si_errno = breakpt;        /* breakpoint or watchpoint id */
 603         info.si_code = signal_code;
 604         info.si_addr = (void __user *)address;
 605         force_sig_info(SIGTRAP, &info, current);
 606 }
 607 #else   /* !CONFIG_PPC_ADV_DEBUG_REGS */
 608 void do_break (struct pt_regs *regs, unsigned long address,
 609                     unsigned long error_code)
 610 {
 611         siginfo_t info;
 612
 613         current->thread.trap_nr = TRAP_HWBKPT;
 614         if (notify_die(DIE_DABR_MATCH, "dabr_match", regs, error_code,
 615                         11, SIGSEGV) == NOTIFY_STOP)
 616                 return;
 617
 618         if (debugger_break_match(regs))
 619                 return;
 620
 621         /* Clear the breakpoint */
 622         hw_breakpoint_disable();
 623
 624         /* Deliver the signal to userspace */
 625         info.si_signo = SIGTRAP;
 626         info.si_errno = 0;
 627         info.si_code = TRAP_HWBKPT;
 628         info.si_addr = (void __user *)address;
 629         force_sig_info(SIGTRAP, &info, current);
 630 }
 631 #endif  /* CONFIG_PPC_ADV_DEBUG_REGS */
 632
 633 static DEFINE_PER_CPU(struct arch_hw_breakpoint, current_brk);
 634
 635 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
 636 /*
 637  * Set the debug registers back to their default "safe" values.
 638  */
 639 static void set_debug_reg_defaults(struct thread_struct *thread)
 640 {
 641         thread->debug.iac1 = thread->debug.iac2 = 0;
 642 #if CONFIG_PPC_ADV_DEBUG_IACS > 2
 643         thread->debug.iac3 = thread->debug.iac4 = 0;
 644 #endif
 645         thread->debug.dac1 = thread->debug.dac2 = 0;
 646 #if CONFIG_PPC_ADV_DEBUG_DVCS > 0
 647         thread->debug.dvc1 = thread->debug.dvc2 = 0;
 648 #endif
 649         thread->debug.dbcr0 = 0;
 650 #ifdef CONFIG_BOOKE
 651         /*
 652          * Force User/Supervisor bits to b11 (user-only MSR[PR]=1)
 653          */
 654         thread->debug.dbcr1 = DBCR1_IAC1US | DBCR1_IAC2US |
 655                         DBCR1_IAC3US | DBCR1_IAC4US;
 656         /*
 657          * Force Data Address Compare User/Supervisor bits to be User-only
 658          * (0b11 MSR[PR]=1) and set all other bits in DBCR2 register to be 0.
 659          */
 660         thread->debug.dbcr2 = DBCR2_DAC1US | DBCR2_DAC2US;
 661 #else
 662         thread->debug.dbcr1 = 0;
 663 #endif
 664 }
 665
 666 static void prime_debug_regs(struct debug_reg *debug)
 667 {
 668         /*
 669          * We could have inherited MSR_DE from userspace, since
 670          * it doesn't get cleared on exception entry.  Make sure
 671          * MSR_DE is clear before we enable any debug events.
 672          */
 673         mtmsr(mfmsr() & ~MSR_DE);
 674
 675         mtspr(SPRN_IAC1, debug->iac1);
 676         mtspr(SPRN_IAC2, debug->iac2);
 677 #if CONFIG_PPC_ADV_DEBUG_IACS > 2
 678         mtspr(SPRN_IAC3, debug->iac3);
 679         mtspr(SPRN_IAC4, debug->iac4);
 680 #endif
 681         mtspr(SPRN_DAC1, debug->dac1);
 682         mtspr(SPRN_DAC2, debug->dac2);
 683 #if CONFIG_PPC_ADV_DEBUG_DVCS > 0
 684         mtspr(SPRN_DVC1, debug->dvc1);
 685         mtspr(SPRN_DVC2, debug->dvc2);
 686 #endif
 687         mtspr(SPRN_DBCR0, debug->dbcr0);
 688         mtspr(SPRN_DBCR1, debug->dbcr1);
 689 #ifdef CONFIG_BOOKE
 690         mtspr(SPRN_DBCR2, debug->dbcr2);
 691 #endif
 692 }
 693 /*
 694  * Unless neither the old or new thread are making use of the
 695  * debug registers, set the debug registers from the values
 696  * stored in the new thread.
 697  */
 698 void switch_booke_debug_regs(struct debug_reg *new_debug)
 699 {
 700         if ((current->thread.debug.dbcr0 & DBCR0_IDM)
 701                 || (new_debug->dbcr0 & DBCR0_IDM))
 702                         prime_debug_regs(new_debug);
 703 }
 704 EXPORT_SYMBOL_GPL(switch_booke_debug_regs);
 705 #else   /* !CONFIG_PPC_ADV_DEBUG_REGS */
 706 #ifndef CONFIG_HAVE_HW_BREAKPOINT
 707 static void set_debug_reg_defaults(struct thread_struct *thread)
 708 {
 709         thread->hw_brk.address = 0;
 710         thread->hw_brk.type = 0;
 711         set_breakpoint(&thread->hw_brk);
 712 }
 713 #endif /* !CONFIG_HAVE_HW_BREAKPOINT */
 714 #endif  /* CONFIG_PPC_ADV_DEBUG_REGS */
 715
 716 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
 717 static inline int __set_dabr(unsigned long dabr, unsigned long dabrx)
 718 {
 719         mtspr(SPRN_DAC1, dabr);
 720 #ifdef CONFIG_PPC_47x
 721         isync();
 722 #endif
 723         return 0;
 724 }
 725 #elif defined(CONFIG_PPC_BOOK3S)
 726 static inline int __set_dabr(unsigned long dabr, unsigned long dabrx)
 727 {
 728         mtspr(SPRN_DABR, dabr);
 729         if (cpu_has_feature(CPU_FTR_DABRX))
 730                 mtspr(SPRN_DABRX, dabrx);
 731         return 0;
 732 }
 733 #else
 734 static inline int __set_dabr(unsigned long dabr, unsigned long dabrx)
 735 {
 736         return -EINVAL;
 737 }
 738 #endif
 739
 740 static inline int set_dabr(struct arch_hw_breakpoint *brk)
 741 {
 742         unsigned long dabr, dabrx;
 743
 744         dabr = brk->address | (brk->type & HW_BRK_TYPE_DABR);
 745         dabrx = ((brk->type >> 3) & 0x7);
 746
 747         if (ppc_md.set_dabr)
 748                 return ppc_md.set_dabr(dabr, dabrx);
 749
 750         return __set_dabr(dabr, dabrx);
 751 }
 752
 753 static inline int set_dawr(struct arch_hw_breakpoint *brk)
 754 {
 755         unsigned long dawr, dawrx, mrd;
 756
 757         dawr = brk->address;
 758
 759         dawrx  = (brk->type & (HW_BRK_TYPE_READ | HW_BRK_TYPE_WRITE)) \
 760                                    << (63 - 58); //* read/write bits */
 761         dawrx |= ((brk->type & (HW_BRK_TYPE_TRANSLATE)) >> 2) \
 762                                    << (63 - 59); //* translate */
 763         dawrx |= (brk->type & (HW_BRK_TYPE_PRIV_ALL)) \
 764                                    >> 3; //* PRIM bits */
 765         /* dawr length is stored in field MDR bits 48:53.  Matches range in
 766            doublewords (64 bits) baised by -1 eg. 0b000000=1DW and
 767            0b111111=64DW.
 768            brk->len is in bytes.
 769            This aligns up to double word size, shifts and does the bias.
 770         */
 771         mrd = ((brk->len + 7) >> 3) - 1;
 772         dawrx |= (mrd & 0x3f) << (63 - 53);
 773
 774         if (ppc_md.set_dawr)
 775                 return ppc_md.set_dawr(dawr, dawrx);
 776         mtspr(SPRN_DAWR, dawr);
 777         mtspr(SPRN_DAWRX, dawrx);
 778         return 0;
 779 }
 780
 781 void __set_breakpoint(struct arch_hw_breakpoint *brk)
 782 {
 783         memcpy(this_cpu_ptr(&current_brk), brk, sizeof(*brk));
 784
 785         if (cpu_has_feature(CPU_FTR_DAWR))
 786                 set_dawr(brk);
 787         else
 788                 set_dabr(brk);
 789 }
 790
 791 void set_breakpoint(struct arch_hw_breakpoint *brk)
 792 {
 793         preempt_disable();
 794         __set_breakpoint(brk);
 795         preempt_enable();
 796 }
 797
 798 #ifdef CONFIG_PPC64
 799 DEFINE_PER_CPU(struct cpu_usage, cpu_usage_array);
 800 #endif
 801
 802 static inline bool hw_brk_match(struct arch_hw_breakpoint *a,
 803                               struct arch_hw_breakpoint *b)
 804 {
 805         if (a->address != b->address)
 806                 return false;
 807         if (a->type != b->type)
 808                 return false;
 809         if (a->len != b->len)
 810                 return false;
 811         return true;
 812 }
 813
 814 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 815
 816 static inline bool tm_enabled(struct task_struct *tsk)
 817 {
 818         return tsk && tsk->thread.regs && (tsk->thread.regs->msr & MSR_TM);
 819 }
 820
 821 static void tm_reclaim_thread(struct thread_struct *thr,
 822                               struct thread_info *ti, uint8_t cause)
 823 {
 824         /*
 825          * Use the current MSR TM suspended bit to track if we have
 826          * checkpointed state outstanding.
 827          * On signal delivery, we'd normally reclaim the checkpointed
 828          * state to obtain stack pointer (see:get_tm_stackpointer()).
 829          * This will then directly return to userspace without going
 830          * through __switch_to(). However, if the stack frame is bad,
 831          * we need to exit this thread which calls __switch_to() which
 832          * will again attempt to reclaim the already saved tm state.
 833          * Hence we need to check that we've not already reclaimed
 834          * this state.
 835          * We do this using the current MSR, rather tracking it in
 836          * some specific thread_struct bit, as it has the additional
 837          * benefit of checking for a potential TM bad thing exception.
 838          */
 839         if (!MSR_TM_SUSPENDED(mfmsr()))
 840                 return;
 841
 842         giveup_all(container_of(thr, struct task_struct, thread));
 843
 844         tm_reclaim(thr, thr->ckpt_regs.msr, cause);
 845 }
 846
 847 void tm_reclaim_current(uint8_t cause)
 848 {
 849         tm_enable();
 850         tm_reclaim_thread(&current->thread, current_thread_info(), cause);
 851 }
 852
 853 static inline void tm_reclaim_task(struct task_struct *tsk)
 854 {
 855         /* We have to work out if we're switching from/to a task that's in the
 856          * middle of a transaction.
 857          *
 858          * In switching we need to maintain a 2nd register state as
 859          * oldtask->thread.ckpt_regs.  We tm_reclaim(oldproc); this saves the
 860          * checkpointed (tbegin) state in ckpt_regs, ckfp_state and
 861          * ckvr_state
 862          *
 863          * We also context switch (save) TFHAR/TEXASR/TFIAR in here.
 864          */
 865         struct thread_struct *thr = &tsk->thread;
 866
 867         if (!thr->regs)
 868                 return;
 869
 870         if (!MSR_TM_ACTIVE(thr->regs->msr))
 871                 goto out_and_saveregs;
 872
 873         TM_DEBUG("--- tm_reclaim on pid %d (NIP=%lx, "
 874                  "ccr=%lx, msr=%lx, trap=%lx)\n",
 875                  tsk->pid, thr->regs->nip,
 876                  thr->regs->ccr, thr->regs->msr,
 877                  thr->regs->trap);
 878
 879         tm_reclaim_thread(thr, task_thread_info(tsk), TM_CAUSE_RESCHED);
 880
 881         TM_DEBUG("--- tm_reclaim on pid %d complete\n",
 882                  tsk->pid);
 883
 884 out_and_saveregs:
 885         /* Always save the regs here, even if a transaction's not active.
 886          * This context-switches a thread's TM info SPRs.  We do it here to
 887          * be consistent with the restore path (in recheckpoint) which
 888          * cannot happen later in _switch().
 889          */
 890         tm_save_sprs(thr);
 891 }
 892
 893 extern void __tm_recheckpoint(struct thread_struct *thread,
 894                               unsigned long orig_msr);
 895
 896 void tm_recheckpoint(struct thread_struct *thread,
 897                      unsigned long orig_msr)
 898 {
 899         unsigned long flags;
 900
 901         if (!(thread->regs->msr & MSR_TM))
 902                 return;
 903
 904         /* We really can't be interrupted here as the TEXASR registers can't
 905          * change and later in the trecheckpoint code, we have a userspace R1.
 906          * So let's hard disable over this region.
 907          */
 908         local_irq_save(flags);
 909         hard_irq_disable();
 910
 911         /* The TM SPRs are restored here, so that TEXASR.FS can be set
 912          * before the trecheckpoint and no explosion occurs.
 913          */
 914         tm_restore_sprs(thread);
 915
 916         __tm_recheckpoint(thread, orig_msr);
 917
 918         local_irq_restore(flags);
 919 }
 920
 921 static inline void tm_recheckpoint_new_task(struct task_struct *new)
 922 {
 923         unsigned long msr;
 924
 925         if (!cpu_has_feature(CPU_FTR_TM))
 926                 return;
 927
 928         /* Recheckpoint the registers of the thread we're about to switch to.
 929          *
 930          * If the task was using FP, we non-lazily reload both the original and
 931          * the speculative FP register states.  This is because the kernel
 932          * doesn't see if/when a TM rollback occurs, so if we take an FP
 933          * unavailable later, we are unable to determine which set of FP regs
 934          * need to be restored.
 935          */
 936         if (!tm_enabled(new))
 937                 return;
 938
 939         if (!MSR_TM_ACTIVE(new->thread.regs->msr)){
 940                 tm_restore_sprs(&new->thread);
 941                 return;
 942         }
 943         msr = new->thread.ckpt_regs.msr;
 944         /* Recheckpoint to restore original checkpointed register state. */
 945         TM_DEBUG("*** tm_recheckpoint of pid %d "
 946                  "(new->msr 0x%lx, new->origmsr 0x%lx)\n",
 947                  new->pid, new->thread.regs->msr, msr);
 948
 949         tm_recheckpoint(&new->thread, msr);
 950
 951         /*
 952          * The checkpointed state has been restored but the live state has
 953          * not, ensure all the math functionality is turned off to trigger
 954          * restore_math() to reload.
 955          */
 956         new->thread.regs->msr &= ~(MSR_FP | MSR_VEC | MSR_VSX);
 957
 958         TM_DEBUG("*** tm_recheckpoint of pid %d complete "
 959                  "(kernel msr 0x%lx)\n",
 960                  new->pid, mfmsr());
 961 }
 962
 963 static inline void __switch_to_tm(struct task_struct *prev,
 964                 struct task_struct *new)
 965 {
 966         if (cpu_has_feature(CPU_FTR_TM)) {
 967                 if (tm_enabled(prev) || tm_enabled(new))
 968                         tm_enable();
 969
 970                 if (tm_enabled(prev)) {
 971                         prev->thread.load_tm++;
 972                         tm_reclaim_task(prev);
 973                         if (!MSR_TM_ACTIVE(prev->thread.regs->msr) && prev->thread.load_tm == 0)
 974                                 prev->thread.regs->msr &= ~MSR_TM;
 975                 }
 976
 977                 tm_recheckpoint_new_task(new);
 978         }
 979 }
 980
 981 /*
 982  * This is called if we are on the way out to userspace and the
 983  * TIF_RESTORE_TM flag is set.  It checks if we need to reload
 984  * FP and/or vector state and does so if necessary.
 985  * If userspace is inside a transaction (whether active or
 986  * suspended) and FP/VMX/VSX instructions have ever been enabled
 987  * inside that transaction, then we have to keep them enabled
 988  * and keep the FP/VMX/VSX state loaded while ever the transaction
 989  * continues.  The reason is that if we didn't, and subsequently
 990  * got a FP/VMX/VSX unavailable interrupt inside a transaction,
 991  * we don't know whether it's the same transaction, and thus we
 992  * don't know which of the checkpointed state and the transactional
 993  * state to use.
 994  */
 995 void restore_tm_state(struct pt_regs *regs)
 996 {
 997         unsigned long msr_diff;
 998
 999         /*
1000          * This is the only moment we should clear TIF_RESTORE_TM as
1001          * it is here that ckpt_regs.msr and pt_regs.msr become the same
1002          * again, anything else could lead to an incorrect ckpt_msr being
1003          * saved and therefore incorrect signal contexts.
1004          */
1005         clear_thread_flag(TIF_RESTORE_TM);
1006         if (!MSR_TM_ACTIVE(regs->msr))
1007                 return;
1008
1009         msr_diff = current->thread.ckpt_regs.msr & ~regs->msr;
1010         msr_diff &= MSR_FP | MSR_VEC | MSR_VSX;
1011
1012         /* Ensure that restore_math() will restore */
1013         if (msr_diff & MSR_FP)
1014                 current->thread.load_fp = 1;
1015 #ifdef CONFIG_ALTIVEC
1016         if (cpu_has_feature(CPU_FTR_ALTIVEC) && msr_diff & MSR_VEC)
1017                 current->thread.load_vec = 1;
1018 #endif
1019         restore_math(regs);
1020
1021         regs->msr |= msr_diff;
1022 }
1023
1024 #else
1025 #define tm_recheckpoint_new_task(new)
1026 #define __switch_to_tm(prev, new)
1027 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
1028
1029 static inline void save_sprs(struct thread_struct *t)
1030 {
1031 #ifdef CONFIG_ALTIVEC
1032         if (cpu_has_feature(CPU_FTR_ALTIVEC))
1033                 t->vrsave = mfspr(SPRN_VRSAVE);
1034 #endif
1035 #ifdef CONFIG_PPC_BOOK3S_64
1036         if (cpu_has_feature(CPU_FTR_DSCR))
1037                 t->dscr = mfspr(SPRN_DSCR);
1038
1039         if (cpu_has_feature(CPU_FTR_ARCH_207S)) {
1040                 t->bescr = mfspr(SPRN_BESCR);
1041                 t->ebbhr = mfspr(SPRN_EBBHR);
1042                 t->ebbrr = mfspr(SPRN_EBBRR);
1043
1044                 t->fscr = mfspr(SPRN_FSCR);
1045
1046                 /*
1047                  * Note that the TAR is not available for use in the kernel.
1048                  * (To provide this, the TAR should be backed up/restored on
1049                  * exception entry/exit instead, and be in pt_regs.  FIXME,
1050                  * this should be in pt_regs anyway (for debug).)
1051                  */
1052                 t->tar = mfspr(SPRN_TAR);
1053         }
1054
1055         if (cpu_has_feature(CPU_FTR_ARCH_300)) {
1056                 /* Conditionally save Load Monitor registers, if enabled */
1057                 if (t->fscr & FSCR_LM) {
1058                         t->lmrr = mfspr(SPRN_LMRR);
1059                         t->lmser = mfspr(SPRN_LMSER);
1060                 }
1061         }
1062 #endif
1063 }
1064
1065 static inline void restore_sprs(struct thread_struct *old_thread,
1066                                 struct thread_struct *new_thread)
1067 {
1068 #ifdef CONFIG_ALTIVEC
1069         if (cpu_has_feature(CPU_FTR_ALTIVEC) &&
1070             old_thread->vrsave != new_thread->vrsave)
1071                 mtspr(SPRN_VRSAVE, new_thread->vrsave);
1072 #endif
1073 #ifdef CONFIG_PPC_BOOK3S_64
1074         if (cpu_has_feature(CPU_FTR_DSCR)) {
1075                 u64 dscr = get_paca()->dscr_default;
1076                 if (new_thread->dscr_inherit)
1077                         dscr = new_thread->dscr;
1078
1079                 if (old_thread->dscr != dscr)
1080                         mtspr(SPRN_DSCR, dscr);
1081         }
1082
1083         if (cpu_has_feature(CPU_FTR_ARCH_207S)) {
1084                 if (old_thread->bescr != new_thread->bescr)
1085                         mtspr(SPRN_BESCR, new_thread->bescr);
1086                 if (old_thread->ebbhr != new_thread->ebbhr)
1087                         mtspr(SPRN_EBBHR, new_thread->ebbhr);
1088                 if (old_thread->ebbrr != new_thread->ebbrr)
1089                         mtspr(SPRN_EBBRR, new_thread->ebbrr);
1090
1091                 if (old_thread->fscr != new_thread->fscr)
1092                         mtspr(SPRN_FSCR, new_thread->fscr);
1093
1094                 if (old_thread->tar != new_thread->tar)
1095                         mtspr(SPRN_TAR, new_thread->tar);
1096         }
1097
1098         if (cpu_has_feature(CPU_FTR_ARCH_300)) {
1099                 /* Conditionally restore Load Monitor registers, if enabled */
1100                 if (new_thread->fscr & FSCR_LM) {
1101                         if (old_thread->lmrr != new_thread->lmrr)
1102                                 mtspr(SPRN_LMRR, new_thread->lmrr);
1103                         if (old_thread->lmser != new_thread->lmser)
1104                                 mtspr(SPRN_LMSER, new_thread->lmser);
1105                 }
1106         }
1107 #endif
1108 }
1109
1110 struct task_struct *__switch_to(struct task_struct *prev,
1111         struct task_struct *new)
1112 {
1113         struct thread_struct *new_thread, *old_thread;
1114         struct task_struct *last;
1115 #ifdef CONFIG_PPC_BOOK3S_64
1116         struct ppc64_tlb_batch *batch;
1117 #endif
1118
1119         new_thread = &new->thread;
1120         old_thread = &current->thread;
1121
1122         WARN_ON(!irqs_disabled());
1123
1124 #ifdef CONFIG_PPC64
1125         /*
1126          * Collect processor utilization data per process
1127          */
1128         if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
1129                 struct cpu_usage *cu = this_cpu_ptr(&cpu_usage_array);
1130                 long unsigned start_tb, current_tb;
1131                 start_tb = old_thread->start_tb;
1132                 cu->current_tb = current_tb = mfspr(SPRN_PURR);
1133                 old_thread->accum_tb += (current_tb - start_tb);
1134                 new_thread->start_tb = current_tb;
1135         }
1136 #endif /* CONFIG_PPC64 */
1137
1138 #ifdef CONFIG_PPC_STD_MMU_64
1139         batch = this_cpu_ptr(&ppc64_tlb_batch);
1140         if (batch->active) {
1141                 current_thread_info()->local_flags |= _TLF_LAZY_MMU;
1142                 if (batch->index)
1143                         __flush_tlb_pending(batch);
1144                 batch->active = 0;
1145         }
1146 #endif /* CONFIG_PPC_STD_MMU_64 */
1147
1148 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
1149         switch_booke_debug_regs(&new->thread.debug);
1150 #else
1151 /*
1152  * For PPC_BOOK3S_64, we use the hw-breakpoint interfaces that would
1153  * schedule DABR
1154  */
1155 #ifndef CONFIG_HAVE_HW_BREAKPOINT
1156         if (unlikely(!hw_brk_match(this_cpu_ptr(&current_brk), &new->thread.hw_brk)))
1157                 __set_breakpoint(&new->thread.hw_brk);
1158 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
1159 #endif
1160
1161         /*
1162          * We need to save SPRs before treclaim/trecheckpoint as these will
1163          * change a number of them.
1164          */
1165         save_sprs(&prev->thread);
1166
1167         /* Save FPU, Altivec, VSX and SPE state */
1168         giveup_all(prev);
1169
1170         __switch_to_tm(prev, new);
1171
1172         /*
1173          * We can't take a PMU exception inside _switch() since there is a
1174          * window where the kernel stack SLB and the kernel stack are out
1175          * of sync. Hard disable here.
1176          */
1177         hard_irq_disable();
1178
1179         /*
1180          * Call restore_sprs() before calling _switch(). If we move it after
1181          * _switch() then we miss out on calling it for new tasks. The reason
1182          * for this is we manually create a stack frame for new tasks that
1183          * directly returns through ret_from_fork() or
1184          * ret_from_kernel_thread(). See copy_thread() for details.
1185          */
1186         restore_sprs(old_thread, new_thread);
1187
1188         last = _switch(old_thread, new_thread);
1189
1190 #ifdef CONFIG_PPC_STD_MMU_64
1191         if (current_thread_info()->local_flags & _TLF_LAZY_MMU) {
1192                 current_thread_info()->local_flags &= ~_TLF_LAZY_MMU;
1193                 batch = this_cpu_ptr(&ppc64_tlb_batch);
1194                 batch->active = 1;
1195         }
1196
1197         if (current_thread_info()->task->thread.regs)
1198                 restore_math(current_thread_info()->task->thread.regs);
1199 #endif /* CONFIG_PPC_STD_MMU_64 */
1200
1201         return last;
1202 }
1203
1204 static int instructions_to_print = 16;
1205
1206 static void show_instructions(struct pt_regs *regs)
1207 {
1208         int i;
1209         unsigned long pc = regs->nip - (instructions_to_print * 3 / 4 *
1210                         sizeof(int));
1211
1212         printk("Instruction dump:");
1213
1214         for (i = 0; i < instructions_to_print; i++) {
1215                 int instr;
1216
1217                 if (!(i % 8))
1218                         printk("\n");
1219
1220 #if !defined(CONFIG_BOOKE)
1221                 /* If executing with the IMMU off, adjust pc rather
1222                  * than print XXXXXXXX.
1223                  */
1224                 if (!(regs->msr & MSR_IR))
1225                         pc = (unsigned long)phys_to_virt(pc);
1226 #endif
1227
1228                 if (!__kernel_text_address(pc) ||
1229                      probe_kernel_address((unsigned int __user *)pc, instr)) {
1230                         printk(KERN_CONT "XXXXXXXX ");
1231                 } else {
1232                         if (regs->nip == pc)
1233                                 printk(KERN_CONT "<%08x> ", instr);
1234                         else
1235                                 printk(KERN_CONT "%08x ", instr);
1236                 }
1237
1238                 pc += sizeof(int);
1239         }
1240
1241         printk("\n");
1242 }
1243
1244 struct regbit {
1245         unsigned long bit;
1246         const char *name;
1247 };
1248
1249 static struct regbit msr_bits[] = {
1250 #if defined(CONFIG_PPC64) && !defined(CONFIG_BOOKE)
1251         {MSR_SF,        "SF"},
1252         {MSR_HV,        "HV"},
1253 #endif
1254         {MSR_VEC,       "VEC"},
1255         {MSR_VSX,       "VSX"},
1256 #ifdef CONFIG_BOOKE
1257         {MSR_CE,        "CE"},
1258 #endif
1259         {MSR_EE,        "EE"},
1260         {MSR_PR,        "PR"},
1261         {MSR_FP,        "FP"},
1262         {MSR_ME,        "ME"},
1263 #ifdef CONFIG_BOOKE
1264         {MSR_DE,        "DE"},
1265 #else
1266         {MSR_SE,        "SE"},
1267         {MSR_BE,        "BE"},
1268 #endif
1269         {MSR_IR,        "IR"},
1270         {MSR_DR,        "DR"},
1271         {MSR_PMM,       "PMM"},
1272 #ifndef CONFIG_BOOKE
1273         {MSR_RI,        "RI"},
1274         {MSR_LE,        "LE"},
1275 #endif
1276         {0,             NULL}
1277 };
1278
1279 static void print_bits(unsigned long val, struct regbit *bits, const char *sep)
1280 {
1281         const char *s = "";
1282
1283         for (; bits->bit; ++bits)
1284                 if (val & bits->bit) {
1285                         printk("%s%s", s, bits->name);
1286                         s = sep;
1287                 }
1288 }
1289
1290 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1291 static struct regbit msr_tm_bits[] = {
1292         {MSR_TS_T,      "T"},
1293         {MSR_TS_S,      "S"},
1294         {MSR_TM,        "E"},
1295         {0,             NULL}
1296 };
1297
1298 static void print_tm_bits(unsigned long val)
1299 {
1300 /*
1301  * This only prints something if at least one of the TM bit is set.
1302  * Inside the TM[], the output means:
1303  *   E: Enabled         (bit 32)
1304  *   S: Suspended       (bit 33)
1305  *   T: Transactional   (bit 34)
1306  */
1307         if (val & (MSR_TM | MSR_TS_S | MSR_TS_T)) {
1308                 printk(",TM[");
1309                 print_bits(val, msr_tm_bits, "");
1310                 printk("]");
1311         }
1312 }
1313 #else
1314 static void print_tm_bits(unsigned long val) {}
1315 #endif
1316
1317 static void print_msr_bits(unsigned long val)
1318 {
1319         printk("<");
1320         print_bits(val, msr_bits, ",");
1321         print_tm_bits(val);
1322         printk(">");
1323 }
1324
1325 #ifdef CONFIG_PPC64
1326 #define REG             "%016lx"
1327 #define REGS_PER_LINE   4
1328 #define LAST_VOLATILE   13
1329 #else
1330 #define REG             "%08lx"
1331 #define REGS_PER_LINE   8
1332 #define LAST_VOLATILE   12
1333 #endif
1334
1335 void show_regs(struct pt_regs * regs)
1336 {
1337         int i, trap;
1338
1339         show_regs_print_info(KERN_DEFAULT);
1340
1341         printk("NIP: "REG" LR: "REG" CTR: "REG"\n",
1342                regs->nip, regs->link, regs->ctr);
1343         printk("REGS: %p TRAP: %04lx   %s  (%s)\n",
1344                regs, regs->trap, print_tainted(), init_utsname()->release);
1345         printk("MSR: "REG" ", regs->msr);
1346         print_msr_bits(regs->msr);
1347         printk("  CR: %08lx  XER: %08lx\n", regs->ccr, regs->xer);
1348         trap = TRAP(regs);
1349         if ((regs->trap != 0xc00) && cpu_has_feature(CPU_FTR_CFAR))
1350                 printk("CFAR: "REG" ", regs->orig_gpr3);
1351         if (trap == 0x200 || trap == 0x300 || trap == 0x600)
1352 #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
1353                 printk("DEAR: "REG" ESR: "REG" ", regs->dar, regs->dsisr);
1354 #else
1355                 printk("DAR: "REG" DSISR: %08lx ", regs->dar, regs->dsisr);
1356 #endif
1357 #ifdef CONFIG_PPC64
1358         printk("SOFTE: %ld ", regs->softe);
1359 #endif
1360 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1361         if (MSR_TM_ACTIVE(regs->msr))
1362                 printk("\nPACATMSCRATCH: %016llx ", get_paca()->tm_scratch);
1363 #endif
1364
1365         for (i = 0;  i < 32;  i++) {
1366                 if ((i % REGS_PER_LINE) == 0)
1367                         printk("\nGPR%02d: ", i);
1368                 printk(REG " ", regs->gpr[i]);
1369                 if (i == LAST_VOLATILE && !FULL_REGS(regs))
1370                         break;
1371         }
1372         printk("\n");
1373 #ifdef CONFIG_KALLSYMS
1374         /*
1375          * Lookup NIP late so we have the best change of getting the
1376          * above info out without failing
1377          */
1378         printk("NIP ["REG"] %pS\n", regs->nip, (void *)regs->nip);
1379         printk("LR ["REG"] %pS\n", regs->link, (void *)regs->link);
1380 #endif
1381         show_stack(current, (unsigned long *) regs->gpr[1]);
1382         if (!user_mode(regs))
1383                 show_instructions(regs);
1384 }
1385
1386 void flush_thread(void)
1387 {
1388 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1389         flush_ptrace_hw_breakpoint(current);
1390 #else /* CONFIG_HAVE_HW_BREAKPOINT */
1391         set_debug_reg_defaults(&current->thread);
1392 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
1393 }
1394
1395 void
1396 release_thread(struct task_struct *t)
1397 {
1398 }
1399
1400 /*
1401  * this gets called so that we can store coprocessor state into memory and
1402  * copy the current task into the new thread.
1403  */
1404 int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
1405 {
1406         flush_all_to_thread(src);
1407         /*
1408          * Flush TM state out so we can copy it.  __switch_to_tm() does this
1409          * flush but it removes the checkpointed state from the current CPU and
1410          * transitions the CPU out of TM mode.  Hence we need to call
1411          * tm_recheckpoint_new_task() (on the same task) to restore the
1412          * checkpointed state back and the TM mode.
1413          *
1414          * Can't pass dst because it isn't ready. Doesn't matter, passing
1415          * dst is only important for __switch_to()
1416          */
1417         __switch_to_tm(src, src);
1418
1419         *dst = *src;
1420
1421         clear_task_ebb(dst);
1422
1423         return 0;
1424 }
1425
1426 static void setup_ksp_vsid(struct task_struct *p, unsigned long sp)
1427 {
1428 #ifdef CONFIG_PPC_STD_MMU_64
1429         unsigned long sp_vsid;
1430         unsigned long llp = mmu_psize_defs[mmu_linear_psize].sllp;
1431
1432         if (radix_enabled())
1433                 return;
1434
1435         if (mmu_has_feature(MMU_FTR_1T_SEGMENT))
1436                 sp_vsid = get_kernel_vsid(sp, MMU_SEGSIZE_1T)
1437                         << SLB_VSID_SHIFT_1T;
1438         else
1439                 sp_vsid = get_kernel_vsid(sp, MMU_SEGSIZE_256M)
1440                         << SLB_VSID_SHIFT;
1441         sp_vsid |= SLB_VSID_KERNEL | llp;
1442         p->thread.ksp_vsid = sp_vsid;
1443 #endif
1444 }
1445
1446 /*
1447  * Copy a thread..
1448  */
1449
1450 /*
1451  * Copy architecture-specific thread state
1452  */
1453 int copy_thread(unsigned long clone_flags, unsigned long usp,
1454                 unsigned long kthread_arg, struct task_struct *p)
1455 {
1456         struct pt_regs *childregs, *kregs;
1457         extern void ret_from_fork(void);
1458         extern void ret_from_kernel_thread(void);
1459         void (*f)(void);
1460         unsigned long sp = (unsigned long)task_stack_page(p) + THREAD_SIZE;
1461         struct thread_info *ti = task_thread_info(p);
1462
1463         klp_init_thread_info(ti);
1464
1465         /* Copy registers */
1466         sp -= sizeof(struct pt_regs);
1467         childregs = (struct pt_regs *) sp;
1468         if (unlikely(p->flags & PF_KTHREAD)) {
1469                 /* kernel thread */
1470                 memset(childregs, 0, sizeof(struct pt_regs));
1471                 childregs->gpr[1] = sp + sizeof(struct pt_regs);
1472                 /* function */
1473                 if (usp)
1474                         childregs->gpr[14] = ppc_function_entry((void *)usp);
1475 #ifdef CONFIG_PPC64
1476                 clear_tsk_thread_flag(p, TIF_32BIT);
1477                 childregs->softe = 1;
1478 #endif
1479                 childregs->gpr[15] = kthread_arg;
1480                 p->thread.regs = NULL;  /* no user register state */
1481                 ti->flags |= _TIF_RESTOREALL;
1482                 f = ret_from_kernel_thread;
1483         } else {
1484                 /* user thread */
1485                 struct pt_regs *regs = current_pt_regs();
1486                 CHECK_FULL_REGS(regs);
1487                 *childregs = *regs;
1488                 if (usp)
1489                         childregs->gpr[1] = usp;
1490                 p->thread.regs = childregs;
1491                 childregs->gpr[3] = 0;  /* Result from fork() */
1492                 if (clone_flags & CLONE_SETTLS) {
1493 #ifdef CONFIG_PPC64
1494                         if (!is_32bit_task())
1495                                 childregs->gpr[13] = childregs->gpr[6];
1496                         else
1497 #endif
1498                                 childregs->gpr[2] = childregs->gpr[6];
1499                 }
1500
1501                 f = ret_from_fork;
1502         }
1503         childregs->msr &= ~(MSR_FP|MSR_VEC|MSR_VSX);
1504         sp -= STACK_FRAME_OVERHEAD;
1505
1506         /*
1507          * The way this works is that at some point in the future
1508          * some task will call _switch to switch to the new task.
1509          * That will pop off the stack frame created below and start
1510          * the new task running at ret_from_fork.  The new task will
1511          * do some house keeping and then return from the fork or clone
1512          * system call, using the stack frame created above.
1513          */
1514         ((unsigned long *)sp)[0] = 0;
1515         sp -= sizeof(struct pt_regs);
1516         kregs = (struct pt_regs *) sp;
1517         sp -= STACK_FRAME_OVERHEAD;
1518         p->thread.ksp = sp;
1519 #ifdef CONFIG_PPC32
1520         p->thread.ksp_limit = (unsigned long)task_stack_page(p) +
1521                                 _ALIGN_UP(sizeof(struct thread_info), 16);
1522 #endif
1523 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1524         p->thread.ptrace_bps[0] = NULL;
1525 #endif
1526
1527         p->thread.fp_save_area = NULL;
1528 #ifdef CONFIG_ALTIVEC
1529         p->thread.vr_save_area = NULL;
1530 #endif
1531
1532         setup_ksp_vsid(p, sp);
1533
1534 #ifdef CONFIG_PPC64
1535         if (cpu_has_feature(CPU_FTR_DSCR)) {
1536                 p->thread.dscr_inherit = current->thread.dscr_inherit;
1537                 p->thread.dscr = mfspr(SPRN_DSCR);
1538         }
1539         if (cpu_has_feature(CPU_FTR_HAS_PPR))
1540                 p->thread.ppr = INIT_PPR;
1541 #endif
1542         kregs->nip = ppc_function_entry(f);
1543         return 0;
1544 }
1545
1546 /*
1547  * Set up a thread for executing a new program
1548  */
1549 void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
1550 {
1551 #ifdef CONFIG_PPC64
1552         unsigned long load_addr = regs->gpr[2]; /* saved by ELF_PLAT_INIT */
1553 #endif
1554
1555         /*
1556          * If we exec out of a kernel thread then thread.regs will not be
1557          * set.  Do it now.
1558          */
1559         if (!current->thread.regs) {
1560                 struct pt_regs *regs = task_stack_page(current) + THREAD_SIZE;
1561                 current->thread.regs = regs - 1;
1562         }
1563
1564 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1565         /*
1566          * Clear any transactional state, we're exec()ing. The cause is
1567          * not important as there will never be a recheckpoint so it's not
1568          * user visible.
1569          */
1570         if (MSR_TM_SUSPENDED(mfmsr()))
1571                 tm_reclaim_current(0);
1572 #endif
1573
1574         memset(regs->gpr, 0, sizeof(regs->gpr));
1575         regs->ctr = 0;
1576         regs->link = 0;
1577         regs->xer = 0;
1578         regs->ccr = 0;
1579         regs->gpr[1] = sp;
1580
1581         /*
1582          * We have just cleared all the nonvolatile GPRs, so make
1583          * FULL_REGS(regs) return true.  This is necessary to allow
1584          * ptrace to examine the thread immediately after exec.
1585          */
1586         regs->trap &= ~1UL;
1587
1588 #ifdef CONFIG_PPC32
1589         regs->mq = 0;
1590         regs->nip = start;
1591         regs->msr = MSR_USER;
1592 #else
1593         if (!is_32bit_task()) {
1594                 unsigned long entry;
1595
1596                 if (is_elf2_task()) {
1597                         /* Look ma, no function descriptors! */
1598                         entry = start;
1599
1600                         /*
1601                          * Ulrich says:
1602                          *   The latest iteration of the ABI requires that when
1603                          *   calling a function (at its global entry point),
1604                          *   the caller must ensure r12 holds the entry point
1605                          *   address (so that the function can quickly
1606                          *   establish addressability).
1607                          */
1608                         regs->gpr[12] = start;
1609                         /* Make sure that's restored on entry to userspace. */
1610                         set_thread_flag(TIF_RESTOREALL);
1611                 } else {
1612                         unsigned long toc;
1613
1614                         /* start is a relocated pointer to the function
1615                          * descriptor for the elf _start routine.  The first
1616                          * entry in the function descriptor is the entry
1617                          * address of _start and the second entry is the TOC
1618                          * value we need to use.
1619                          */
1620                         __get_user(entry, (unsigned long __user *)start);
1621                         __get_user(toc, (unsigned long __user *)start+1);
1622
1623                         /* Check whether the e_entry function descriptor entries
1624                          * need to be relocated before we can use them.
1625                          */
1626                         if (load_addr != 0) {
1627                                 entry += load_addr;
1628                                 toc   += load_addr;
1629                         }
1630                         regs->gpr[2] = toc;
1631                 }
1632                 regs->nip = entry;
1633                 regs->msr = MSR_USER64;
1634         } else {
1635                 regs->nip = start;
1636                 regs->gpr[2] = 0;
1637                 regs->msr = MSR_USER32;
1638         }
1639 #endif
1640 #ifdef CONFIG_VSX
1641         current->thread.used_vsr = 0;
1642 #endif
1643         memset(&current->thread.fp_state, 0, sizeof(current->thread.fp_state));
1644         current->thread.fp_save_area = NULL;
1645 #ifdef CONFIG_ALTIVEC
1646         memset(&current->thread.vr_state, 0, sizeof(current->thread.vr_state));
1647         current->thread.vr_state.vscr.u[3] = 0x00010000; /* Java mode disabled */
1648         current->thread.vr_save_area = NULL;
1649         current->thread.vrsave = 0;
1650         current->thread.used_vr = 0;
1651 #endif /* CONFIG_ALTIVEC */
1652 #ifdef CONFIG_SPE
1653         memset(current->thread.evr, 0, sizeof(current->thread.evr));
1654         current->thread.acc = 0;
1655         current->thread.spefscr = 0;
1656         current->thread.used_spe = 0;
1657 #endif /* CONFIG_SPE */
1658 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1659         current->thread.tm_tfhar = 0;
1660         current->thread.tm_texasr = 0;
1661         current->thread.tm_tfiar = 0;
1662 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
1663 }
1664 EXPORT_SYMBOL(start_thread);
1665
1666 #define PR_FP_ALL_EXCEPT (PR_FP_EXC_DIV | PR_FP_EXC_OVF | PR_FP_EXC_UND \
1667                 | PR_FP_EXC_RES | PR_FP_EXC_INV)
1668
1669 int set_fpexc_mode(struct task_struct *tsk, unsigned int val)
1670 {
1671         struct pt_regs *regs = tsk->thread.regs;
1672
1673         /* This is a bit hairy.  If we are an SPE enabled  processor
1674          * (have embedded fp) we store the IEEE exception enable flags in
1675          * fpexc_mode.  fpexc_mode is also used for setting FP exception
1676          * mode (asyn, precise, disabled) for 'Classic' FP. */
1677         if (val & PR_FP_EXC_SW_ENABLE) {
1678 #ifdef CONFIG_SPE
1679                 if (cpu_has_feature(CPU_FTR_SPE)) {
1680                         /*
1681                          * When the sticky exception bits are set
1682                          * directly by userspace, it must call prctl
1683                          * with PR_GET_FPEXC (with PR_FP_EXC_SW_ENABLE
1684                          * in the existing prctl settings) or
1685                          * PR_SET_FPEXC (with PR_FP_EXC_SW_ENABLE in
1686                          * the bits being set).  <fenv.h> functions
1687                          * saving and restoring the whole
1688                          * floating-point environment need to do so
1689                          * anyway to restore the prctl settings from
1690                          * the saved environment.
1691                          */
1692                         tsk->thread.spefscr_last = mfspr(SPRN_SPEFSCR);
1693                         tsk->thread.fpexc_mode = val &
1694                                 (PR_FP_EXC_SW_ENABLE | PR_FP_ALL_EXCEPT);
1695                         return 0;
1696                 } else {
1697                         return -EINVAL;
1698                 }
1699 #else
1700                 return -EINVAL;
1701 #endif
1702         }
1703
1704         /* on a CONFIG_SPE this does not hurt us.  The bits that
1705          * __pack_fe01 use do not overlap with bits used for
1706          * PR_FP_EXC_SW_ENABLE.  Additionally, the MSR[FE0,FE1] bits
1707          * on CONFIG_SPE implementations are reserved so writing to
1708          * them does not change anything */
1709         if (val > PR_FP_EXC_PRECISE)
1710                 return -EINVAL;
1711         tsk->thread.fpexc_mode = __pack_fe01(val);
1712         if (regs != NULL && (regs->msr & MSR_FP) != 0)
1713                 regs->msr = (regs->msr & ~(MSR_FE0|MSR_FE1))
1714                         | tsk->thread.fpexc_mode;
1715         return 0;
1716 }
1717
1718 int get_fpexc_mode(struct task_struct *tsk, unsigned long adr)
1719 {
1720         unsigned int val;
1721
1722         if (tsk->thread.fpexc_mode & PR_FP_EXC_SW_ENABLE)
1723 #ifdef CONFIG_SPE
1724                 if (cpu_has_feature(CPU_FTR_SPE)) {
1725                         /*
1726                          * When the sticky exception bits are set
1727                          * directly by userspace, it must call prctl
1728                          * with PR_GET_FPEXC (with PR_FP_EXC_SW_ENABLE
1729                          * in the existing prctl settings) or
1730                          * PR_SET_FPEXC (with PR_FP_EXC_SW_ENABLE in
1731                          * the bits being set).  <fenv.h> functions
1732                          * saving and restoring the whole
1733                          * floating-point environment need to do so
1734                          * anyway to restore the prctl settings from
1735                          * the saved environment.
1736                          */
1737                         tsk->thread.spefscr_last = mfspr(SPRN_SPEFSCR);
1738                         val = tsk->thread.fpexc_mode;
1739                 } else
1740                         return -EINVAL;
1741 #else
1742                 return -EINVAL;
1743 #endif
1744         else
1745                 val = __unpack_fe01(tsk->thread.fpexc_mode);
1746         return put_user(val, (unsigned int __user *) adr);
1747 }
1748
1749 int set_endian(struct task_struct *tsk, unsigned int val)
1750 {
1751         struct pt_regs *regs = tsk->thread.regs;
1752
1753         if ((val == PR_ENDIAN_LITTLE && !cpu_has_feature(CPU_FTR_REAL_LE)) ||
1754             (val == PR_ENDIAN_PPC_LITTLE && !cpu_has_feature(CPU_FTR_PPC_LE)))
1755                 return -EINVAL;
1756
1757         if (regs == NULL)
1758                 return -EINVAL;
1759
1760         if (val == PR_ENDIAN_BIG)
1761                 regs->msr &= ~MSR_LE;
1762         else if (val == PR_ENDIAN_LITTLE || val == PR_ENDIAN_PPC_LITTLE)
1763                 regs->msr |= MSR_LE;
1764         else
1765                 return -EINVAL;
1766
1767         return 0;
1768 }
1769
1770 int get_endian(struct task_struct *tsk, unsigned long adr)
1771 {
1772         struct pt_regs *regs = tsk->thread.regs;
1773         unsigned int val;
1774
1775         if (!cpu_has_feature(CPU_FTR_PPC_LE) &&
1776             !cpu_has_feature(CPU_FTR_REAL_LE))
1777                 return -EINVAL;
1778
1779         if (regs == NULL)
1780                 return -EINVAL;
1781
1782         if (regs->msr & MSR_LE) {
1783                 if (cpu_has_feature(CPU_FTR_REAL_LE))
1784                         val = PR_ENDIAN_LITTLE;
1785                 else
1786                         val = PR_ENDIAN_PPC_LITTLE;
1787         } else
1788                 val = PR_ENDIAN_BIG;
1789
1790         return put_user(val, (unsigned int __user *)adr);
1791 }
1792
1793 int set_unalign_ctl(struct task_struct *tsk, unsigned int val)
1794 {
1795         tsk->thread.align_ctl = val;
1796         return 0;
1797 }
1798
1799 int get_unalign_ctl(struct task_struct *tsk, unsigned long adr)
1800 {
1801         return put_user(tsk->thread.align_ctl, (unsigned int __user *)adr);
1802 }
1803
1804 static inline int valid_irq_stack(unsigned long sp, struct task_struct *p,
1805                                   unsigned long nbytes)
1806 {
1807         unsigned long stack_page;
1808         unsigned long cpu = task_cpu(p);
1809
1810         /*
1811          * Avoid crashing if the stack has overflowed and corrupted
1812          * task_cpu(p), which is in the thread_info struct.
1813          */
1814         if (cpu < NR_CPUS && cpu_possible(cpu)) {
1815                 stack_page = (unsigned long) hardirq_ctx[cpu];
1816                 if (sp >= stack_page + sizeof(struct thread_struct)
1817                     && sp <= stack_page + THREAD_SIZE - nbytes)
1818                         return 1;
1819
1820                 stack_page = (unsigned long) softirq_ctx[cpu];
1821                 if (sp >= stack_page + sizeof(struct thread_struct)
1822                     && sp <= stack_page + THREAD_SIZE - nbytes)
1823                         return 1;
1824         }
1825         return 0;
1826 }
1827
1828 int validate_sp(unsigned long sp, struct task_struct *p,
1829                        unsigned long nbytes)
1830 {
1831         unsigned long stack_page = (unsigned long)task_stack_page(p);
1832
1833         if (sp >= stack_page + sizeof(struct thread_struct)
1834             && sp <= stack_page + THREAD_SIZE - nbytes)
1835                 return 1;
1836
1837         return valid_irq_stack(sp, p, nbytes);
1838 }
1839
1840 EXPORT_SYMBOL(validate_sp);
1841
1842 unsigned long get_wchan(struct task_struct *p)
1843 {
1844         unsigned long ip, sp;
1845         int count = 0;
1846
1847         if (!p || p == current || p->state == TASK_RUNNING)
1848                 return 0;
1849
1850         sp = p->thread.ksp;
1851         if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD))
1852                 return 0;
1853
1854         do {
1855                 sp = *(unsigned long *)sp;
1856                 if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD))
1857                         return 0;
1858                 if (count > 0) {
1859                         ip = ((unsigned long *)sp)[STACK_FRAME_LR_SAVE];
1860                         if (!in_sched_functions(ip))
1861                                 return ip;
1862                 }
1863         } while (count++ < 16);
1864         return 0;
1865 }
1866
1867 static int kstack_depth_to_print = CONFIG_PRINT_STACK_DEPTH;
1868
1869 void show_stack(struct task_struct *tsk, unsigned long *stack)
1870 {
1871         unsigned long sp, ip, lr, newsp;
1872         int count = 0;
1873         int firstframe = 1;
1874 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1875         int curr_frame = current->curr_ret_stack;
1876         extern void return_to_handler(void);
1877         unsigned long rth = (unsigned long)return_to_handler;
1878 #endif
1879
1880         sp = (unsigned long) stack;
1881         if (tsk == NULL)
1882                 tsk = current;
1883         if (sp == 0) {
1884                 if (tsk == current)
1885                         sp = current_stack_pointer();
1886                 else
1887                         sp = tsk->thread.ksp;
1888         }
1889
1890         lr = 0;
1891         printk("Call Trace:\n");
1892         do {
1893                 if (!validate_sp(sp, tsk, STACK_FRAME_OVERHEAD))
1894                         return;
1895
1896                 stack = (unsigned long *) sp;
1897                 newsp = stack[0];
1898                 ip = stack[STACK_FRAME_LR_SAVE];
1899                 if (!firstframe || ip != lr) {
1900                         printk("["REG"] ["REG"] %pS", sp, ip, (void *)ip);
1901 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1902                         if ((ip == rth) && curr_frame >= 0) {
1903                                 printk(" (%pS)",
1904                                        (void *)current->ret_stack[curr_frame].ret);
1905                                 curr_frame--;
1906                         }
1907 #endif
1908                         if (firstframe)
1909                                 printk(" (unreliable)");
1910                         printk("\n");
1911                 }
1912                 firstframe = 0;
1913
1914                 /*
1915                  * See if this is an exception frame.
1916                  * We look for the "regshere" marker in the current frame.
1917                  */
1918                 if (validate_sp(sp, tsk, STACK_INT_FRAME_SIZE)
1919                     && stack[STACK_FRAME_MARKER] == STACK_FRAME_REGS_MARKER) {
1920                         struct pt_regs *regs = (struct pt_regs *)
1921                                 (sp + STACK_FRAME_OVERHEAD);
1922                         lr = regs->link;
1923                         printk("--- interrupt: %lx at %pS\n    LR = %pS\n",
1924                                regs->trap, (void *)regs->nip, (void *)lr);
1925                         firstframe = 1;
1926                 }
1927
1928                 sp = newsp;
1929         } while (count++ < kstack_depth_to_print);
1930 }
1931
1932 #ifdef CONFIG_PPC64
1933 /* Called with hard IRQs off */
1934 void notrace __ppc64_runlatch_on(void)
1935 {
1936         struct thread_info *ti = current_thread_info();
1937         unsigned long ctrl;
1938
1939         ctrl = mfspr(SPRN_CTRLF);
1940         ctrl |= CTRL_RUNLATCH;
1941         mtspr(SPRN_CTRLT, ctrl);
1942
1943         ti->local_flags |= _TLF_RUNLATCH;
1944 }
1945
1946 /* Called with hard IRQs off */
1947 void notrace __ppc64_runlatch_off(void)
1948 {
1949         struct thread_info *ti = current_thread_info();
1950         unsigned long ctrl;
1951
1952         ti->local_flags &= ~_TLF_RUNLATCH;
1953
1954         ctrl = mfspr(SPRN_CTRLF);
1955         ctrl &= ~CTRL_RUNLATCH;
1956         mtspr(SPRN_CTRLT, ctrl);
1957 }
1958 #endif /* CONFIG_PPC64 */
1959
1960 unsigned long arch_align_stack(unsigned long sp)
1961 {
1962         if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
1963                 sp -= get_random_int() & ~PAGE_MASK;
1964         return sp & ~0xf;
1965 }
1966
1967 static inline unsigned long brk_rnd(void)
1968 {
1969         unsigned long rnd = 0;
1970
1971         /* 8MB for 32bit, 1GB for 64bit */
1972         if (is_32bit_task())
1973                 rnd = (get_random_long() % (1UL<<(23-PAGE_SHIFT)));
1974         else
1975                 rnd = (get_random_long() % (1UL<<(30-PAGE_SHIFT)));
1976
1977         return rnd << PAGE_SHIFT;
1978 }
1979
1980 unsigned long arch_randomize_brk(struct mm_struct *mm)
1981 {
1982         unsigned long base = mm->brk;
1983         unsigned long ret;
1984
1985 #ifdef CONFIG_PPC_STD_MMU_64
1986         /*
1987          * If we are using 1TB segments and we are allowed to randomise
1988          * the heap, we can put it above 1TB so it is backed by a 1TB
1989          * segment. Otherwise the heap will be in the bottom 1TB
1990          * which always uses 256MB segments and this may result in a
1991          * performance penalty. We don't need to worry about radix. For
1992          * radix, mmu_highuser_ssize remains unchanged from 256MB.
1993          */
1994         if (!is_32bit_task() && (mmu_highuser_ssize == MMU_SEGSIZE_1T))
1995                 base = max_t(unsigned long, mm->brk, 1UL << SID_SHIFT_1T);
1996 #endif
1997
1998         ret = PAGE_ALIGN(base + brk_rnd());
1999
2000         if (ret < mm->brk)
2001                 return mm->brk;
2002
2003         return ret;
2004 }
2005