arch/x86/kernel/process_64.c

   1 /*
   2  *  Copyright (C) 1995  Linus Torvalds
   3  *
   4  *  Pentium III FXSR, SSE support
   5  *      Gareth Hughes <gareth@valinux.com>, May 2000
   6  *
   7  *  X86-64 port
   8  *      Andi Kleen.
   9  *
  10  *      CPU hotplug support - ashok.raj@intel.com
  11  */
  12
  13 /*
  14  * This file handles the architecture-dependent parts of process handling..
  15  */
  16
  17 #include <linux/stackprotector.h>
  18 #include <linux/cpu.h>
  19 #include <linux/errno.h>
  20 #include <linux/sched.h>
  21 #include <linux/fs.h>
  22 #include <linux/kernel.h>
  23 #include <linux/mm.h>
  24 #include <linux/elfcore.h>
  25 #include <linux/smp.h>
  26 #include <linux/slab.h>
  27 #include <linux/user.h>
  28 #include <linux/interrupt.h>
  29 #include <linux/delay.h>
  30 #include <linux/module.h>
  31 #include <linux/ptrace.h>
  32 #include <linux/notifier.h>
  33 #include <linux/kprobes.h>
  34 #include <linux/kdebug.h>
  35 #include <linux/tick.h>
  36 #include <linux/prctl.h>
  37 #include <linux/uaccess.h>
  38 #include <linux/io.h>
  39 #include <linux/ftrace.h>
  40 #include <linux/cpuidle.h>
  41
  42 #include <asm/pgtable.h>
  43 #include <asm/system.h>
  44 #include <asm/processor.h>
  45 #include <asm/i387.h>
  46 #include <asm/mmu_context.h>
  47 #include <asm/prctl.h>
  48 #include <asm/desc.h>
  49 #include <asm/proto.h>
  50 #include <asm/ia32.h>
  51 #include <asm/idle.h>
  52 #include <asm/syscalls.h>
  53 #include <asm/debugreg.h>
  54 #include <asm/nmi.h>
  55
  56 asmlinkage extern void ret_from_fork(void);
  57
  58 DEFINE_PER_CPU(unsigned long, old_rsp);
  59 static DEFINE_PER_CPU(unsigned char, is_idle);
  60
  61 static ATOMIC_NOTIFIER_HEAD(idle_notifier);
  62
  63 void idle_notifier_register(struct notifier_block *n)
  64 {
  65         atomic_notifier_chain_register(&idle_notifier, n);
  66 }
  67 EXPORT_SYMBOL_GPL(idle_notifier_register);
  68
  69 void idle_notifier_unregister(struct notifier_block *n)
  70 {
  71         atomic_notifier_chain_unregister(&idle_notifier, n);
  72 }
  73 EXPORT_SYMBOL_GPL(idle_notifier_unregister);
  74
  75 void enter_idle(void)
  76 {
  77         percpu_write(is_idle, 1);
  78         atomic_notifier_call_chain(&idle_notifier, IDLE_START, NULL);
  79 }
  80
  81 static void __exit_idle(void)
  82 {
  83         if (x86_test_and_clear_bit_percpu(0, is_idle) == 0)
  84                 return;
  85         atomic_notifier_call_chain(&idle_notifier, IDLE_END, NULL);
  86 }
  87
  88 /* Called from interrupts to signify idle end */
  89 void exit_idle(void)
  90 {
  91         /* idle loop has pid 0 */
  92         if (current->pid)
  93                 return;
  94         __exit_idle();
  95 }
  96
  97 #ifndef CONFIG_SMP
  98 static inline void play_dead(void)
  99 {
 100         BUG();
 101 }
 102 #endif
 103
 104 /*
 105  * The idle thread. There's no useful work to be
 106  * done, so just try to conserve power and have a
 107  * low exit latency (ie sit in a loop waiting for
 108  * somebody to say that they'd like to reschedule)
 109  */
 110 void cpu_idle(void)
 111 {
 112         current_thread_info()->status |= TS_POLLING;
 113
 114         /*
 115          * If we're the non-boot CPU, nothing set the stack canary up
 116          * for us.  CPU0 already has it initialized but no harm in
 117          * doing it again.  This is a good place for updating it, as
 118          * we wont ever return from this function (so the invalid
 119          * canaries already on the stack wont ever trigger).
 120          */
 121         boot_init_stack_canary();
 122
 123         /* endless idle loop with no priority at all */
 124         while (1) {
 125                 tick_nohz_stop_sched_tick(1);
 126                 while (!need_resched()) {
 127
 128                         rmb();
 129
 130                         if (cpu_is_offline(smp_processor_id()))
 131                                 play_dead();
 132                         /*
 133                          * Idle routines should keep interrupts disabled
 134                          * from here on, until they go to idle.
 135                          * Otherwise, idle callbacks can misfire.
 136                          */
 137                         local_touch_nmi();
 138                         local_irq_disable();
 139                         enter_idle();
 140                         /* Don't trace irqs off for idle */
 141                         stop_critical_timings();
 142                         if (cpuidle_idle_call())
 143                                 pm_idle();
 144                         start_critical_timings();
 145
 146                         /* In many cases the interrupt that ended idle
 147                            has already called exit_idle. But some idle
 148                            loops can be woken up without interrupt. */
 149                         __exit_idle();
 150                 }
 151
 152                 tick_nohz_restart_sched_tick();
 153                 preempt_enable_no_resched();
 154                 schedule();
 155                 preempt_disable();
 156         }
 157 }
 158
 159 /* Prints also some state that isn't saved in the pt_regs */
 160 void __show_regs(struct pt_regs *regs, int all)
 161 {
 162         unsigned long cr0 = 0L, cr2 = 0L, cr3 = 0L, cr4 = 0L, fs, gs, shadowgs;
 163         unsigned long d0, d1, d2, d3, d6, d7;
 164         unsigned int fsindex, gsindex;
 165         unsigned int ds, cs, es;
 166
 167         show_regs_common();
 168         printk(KERN_DEFAULT "RIP: %04lx:[<%016lx>] ", regs->cs & 0xffff, regs->ip);
 169         printk_address(regs->ip, 1);
 170         printk(KERN_DEFAULT "RSP: %04lx:%016lx  EFLAGS: %08lx\n", regs->ss,
 171                         regs->sp, regs->flags);
 172         printk(KERN_DEFAULT "RAX: %016lx RBX: %016lx RCX: %016lx\n",
 173                regs->ax, regs->bx, regs->cx);
 174         printk(KERN_DEFAULT "RDX: %016lx RSI: %016lx RDI: %016lx\n",
 175                regs->dx, regs->si, regs->di);
 176         printk(KERN_DEFAULT "RBP: %016lx R08: %016lx R09: %016lx\n",
 177                regs->bp, regs->r8, regs->r9);
 178         printk(KERN_DEFAULT "R10: %016lx R11: %016lx R12: %016lx\n",
 179                regs->r10, regs->r11, regs->r12);
 180         printk(KERN_DEFAULT "R13: %016lx R14: %016lx R15: %016lx\n",
 181                regs->r13, regs->r14, regs->r15);
 182
 183         asm("movl %%ds,%0" : "=r" (ds));
 184         asm("movl %%cs,%0" : "=r" (cs));
 185         asm("movl %%es,%0" : "=r" (es));
 186         asm("movl %%fs,%0" : "=r" (fsindex));
 187         asm("movl %%gs,%0" : "=r" (gsindex));
 188
 189         rdmsrl(MSR_FS_BASE, fs);
 190         rdmsrl(MSR_GS_BASE, gs);
 191         rdmsrl(MSR_KERNEL_GS_BASE, shadowgs);
 192
 193         if (!all)
 194                 return;
 195
 196         cr0 = read_cr0();
 197         cr2 = read_cr2();
 198         cr3 = read_cr3();
 199         cr4 = read_cr4();
 200
 201         printk(KERN_DEFAULT "FS:  %016lx(%04x) GS:%016lx(%04x) knlGS:%016lx\n",
 202                fs, fsindex, gs, gsindex, shadowgs);
 203         printk(KERN_DEFAULT "CS:  %04x DS: %04x ES: %04x CR0: %016lx\n", cs, ds,
 204                         es, cr0);
 205         printk(KERN_DEFAULT "CR2: %016lx CR3: %016lx CR4: %016lx\n", cr2, cr3,
 206                         cr4);
 207
 208         get_debugreg(d0, 0);
 209         get_debugreg(d1, 1);
 210         get_debugreg(d2, 2);
 211         printk(KERN_DEFAULT "DR0: %016lx DR1: %016lx DR2: %016lx\n", d0, d1, d2);
 212         get_debugreg(d3, 3);
 213         get_debugreg(d6, 6);
 214         get_debugreg(d7, 7);
 215         printk(KERN_DEFAULT "DR3: %016lx DR6: %016lx DR7: %016lx\n", d3, d6, d7);
 216 }
 217
 218 void release_thread(struct task_struct *dead_task)
 219 {
 220         if (dead_task->mm) {
 221                 if (dead_task->mm->context.size) {
 222                         printk("WARNING: dead process %8s still has LDT? <%p/%d>\n",
 223                                         dead_task->comm,
 224                                         dead_task->mm->context.ldt,
 225                                         dead_task->mm->context.size);
 226                         BUG();
 227                 }
 228         }
 229 }
 230
 231 static inline void set_32bit_tls(struct task_struct *t, int tls, u32 addr)
 232 {
 233         struct user_desc ud = {
 234                 .base_addr = addr,
 235                 .limit = 0xfffff,
 236                 .seg_32bit = 1,
 237                 .limit_in_pages = 1,
 238                 .useable = 1,
 239         };
 240         struct desc_struct *desc = t->thread.tls_array;
 241         desc += tls;
 242         fill_ldt(desc, &ud);
 243 }
 244
 245 static inline u32 read_32bit_tls(struct task_struct *t, int tls)
 246 {
 247         return get_desc_base(&t->thread.tls_array[tls]);
 248 }
 249
 250 /*
 251  * This gets called before we allocate a new thread and copy
 252  * the current task into it.
 253  */
 254 void prepare_to_copy(struct task_struct *tsk)
 255 {
 256         unlazy_fpu(tsk);
 257 }
 258
 259 int copy_thread(unsigned long clone_flags, unsigned long sp,
 260                 unsigned long unused,
 261         struct task_struct *p, struct pt_regs *regs)
 262 {
 263         int err;
 264         struct pt_regs *childregs;
 265         struct task_struct *me = current;
 266
 267         childregs = ((struct pt_regs *)
 268                         (THREAD_SIZE + task_stack_page(p))) - 1;
 269         *childregs = *regs;
 270
 271         childregs->ax = 0;
 272         if (user_mode(regs))
 273                 childregs->sp = sp;
 274         else
 275                 childregs->sp = (unsigned long)childregs;
 276
 277         p->thread.sp = (unsigned long) childregs;
 278         p->thread.sp0 = (unsigned long) (childregs+1);
 279         p->thread.usersp = me->thread.usersp;
 280
 281         set_tsk_thread_flag(p, TIF_FORK);
 282
 283         p->thread.io_bitmap_ptr = NULL;
 284
 285         savesegment(gs, p->thread.gsindex);
 286         p->thread.gs = p->thread.gsindex ? 0 : me->thread.gs;
 287         savesegment(fs, p->thread.fsindex);
 288         p->thread.fs = p->thread.fsindex ? 0 : me->thread.fs;
 289         savesegment(es, p->thread.es);
 290         savesegment(ds, p->thread.ds);
 291
 292         err = -ENOMEM;
 293         memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
 294
 295         if (unlikely(test_tsk_thread_flag(me, TIF_IO_BITMAP))) {
 296                 p->thread.io_bitmap_ptr = kmalloc(IO_BITMAP_BYTES, GFP_KERNEL);
 297                 if (!p->thread.io_bitmap_ptr) {
 298                         p->thread.io_bitmap_max = 0;
 299                         return -ENOMEM;
 300                 }
 301                 memcpy(p->thread.io_bitmap_ptr, me->thread.io_bitmap_ptr,
 302                                 IO_BITMAP_BYTES);
 303                 set_tsk_thread_flag(p, TIF_IO_BITMAP);
 304         }
 305
 306         /*
 307          * Set a new TLS for the child thread?
 308          */
 309         if (clone_flags & CLONE_SETTLS) {
 310 #ifdef CONFIG_IA32_EMULATION
 311                 if (test_thread_flag(TIF_IA32))
 312                         err = do_set_thread_area(p, -1,
 313                                 (struct user_desc __user *)childregs->si, 0);
 314                 else
 315 #endif
 316                         err = do_arch_prctl(p, ARCH_SET_FS, childregs->r8);
 317                 if (err)
 318                         goto out;
 319         }
 320         err = 0;
 321 out:
 322         if (err && p->thread.io_bitmap_ptr) {
 323                 kfree(p->thread.io_bitmap_ptr);
 324                 p->thread.io_bitmap_max = 0;
 325         }
 326
 327         return err;
 328 }
 329
 330 static void
 331 start_thread_common(struct pt_regs *regs, unsigned long new_ip,
 332                     unsigned long new_sp,
 333                     unsigned int _cs, unsigned int _ss, unsigned int _ds)
 334 {
 335         loadsegment(fs, 0);
 336         loadsegment(es, _ds);
 337         loadsegment(ds, _ds);
 338         load_gs_index(0);
 339         regs->ip                = new_ip;
 340         regs->sp                = new_sp;
 341         percpu_write(old_rsp, new_sp);
 342         regs->cs                = _cs;
 343         regs->ss                = _ss;
 344         regs->flags             = X86_EFLAGS_IF;
 345         /*
 346          * Free the old FP and other extended state
 347          */
 348         free_thread_xstate(current);
 349 }
 350
 351 void
 352 start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp)
 353 {
 354         start_thread_common(regs, new_ip, new_sp,
 355                             __USER_CS, __USER_DS, 0);
 356 }
 357
 358 #ifdef CONFIG_IA32_EMULATION
 359 void start_thread_ia32(struct pt_regs *regs, u32 new_ip, u32 new_sp)
 360 {
 361         start_thread_common(regs, new_ip, new_sp,
 362                             __USER32_CS, __USER32_DS, __USER32_DS);
 363 }
 364 #endif
 365
 366 /*
 367  *      switch_to(x,y) should switch tasks from x to y.
 368  *
 369  * This could still be optimized:
 370  * - fold all the options into a flag word and test it with a single test.
 371  * - could test fs/gs bitsliced
 372  *
 373  * Kprobes not supported here. Set the probe on schedule instead.
 374  * Function graph tracer not supported too.
 375  */
 376 __notrace_funcgraph struct task_struct *
 377 __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 378 {
 379         struct thread_struct *prev = &prev_p->thread;
 380         struct thread_struct *next = &next_p->thread;
 381         int cpu = smp_processor_id();
 382         struct tss_struct *tss = &per_cpu(init_tss, cpu);
 383         unsigned fsindex, gsindex;
 384         bool preload_fpu;
 385
 386         /*
 387          * If the task has used fpu the last 5 timeslices, just do a full
 388          * restore of the math state immediately to avoid the trap; the
 389          * chances of needing FPU soon are obviously high now
 390          */
 391         preload_fpu = tsk_used_math(next_p) && next_p->fpu_counter > 5;
 392
 393         /* we're going to use this soon, after a few expensive things */
 394         if (preload_fpu)
 395                 prefetch(next->fpu.state);
 396
 397         /*
 398          * Reload esp0, LDT and the page table pointer:
 399          */
 400         load_sp0(tss, next);
 401
 402         /*
 403          * Switch DS and ES.
 404          * This won't pick up thread selector changes, but I guess that is ok.
 405          */
 406         savesegment(es, prev->es);
 407         if (unlikely(next->es | prev->es))
 408                 loadsegment(es, next->es);
 409
 410         savesegment(ds, prev->ds);
 411         if (unlikely(next->ds | prev->ds))
 412                 loadsegment(ds, next->ds);
 413
 414
 415         /* We must save %fs and %gs before load_TLS() because
 416          * %fs and %gs may be cleared by load_TLS().
 417          *
 418          * (e.g. xen_load_tls())
 419          */
 420         savesegment(fs, fsindex);
 421         savesegment(gs, gsindex);
 422
 423         load_TLS(next, cpu);
 424
 425         /* Must be after DS reload */
 426         __unlazy_fpu(prev_p);
 427
 428         /* Make sure cpu is ready for new context */
 429         if (preload_fpu)
 430                 clts();
 431
 432         /*
 433          * Leave lazy mode, flushing any hypercalls made here.
 434          * This must be done before restoring TLS segments so
 435          * the GDT and LDT are properly updated, and must be
 436          * done before math_state_restore, so the TS bit is up
 437          * to date.
 438          */
 439         arch_end_context_switch(next_p);
 440
 441         /*
 442          * Switch FS and GS.
 443          *
 444          * Segment register != 0 always requires a reload.  Also
 445          * reload when it has changed.  When prev process used 64bit
 446          * base always reload to avoid an information leak.
 447          */
 448         if (unlikely(fsindex | next->fsindex | prev->fs)) {
 449                 loadsegment(fs, next->fsindex);
 450                 /*
 451                  * Check if the user used a selector != 0; if yes
 452                  *  clear 64bit base, since overloaded base is always
 453                  *  mapped to the Null selector
 454                  */
 455                 if (fsindex)
 456                         prev->fs = 0;
 457         }
 458         /* when next process has a 64bit base use it */
 459         if (next->fs)
 460                 wrmsrl(MSR_FS_BASE, next->fs);
 461         prev->fsindex = fsindex;
 462
 463         if (unlikely(gsindex | next->gsindex | prev->gs)) {
 464                 load_gs_index(next->gsindex);
 465                 if (gsindex)
 466                         prev->gs = 0;
 467         }
 468         if (next->gs)
 469                 wrmsrl(MSR_KERNEL_GS_BASE, next->gs);
 470         prev->gsindex = gsindex;
 471
 472         /*
 473          * Switch the PDA and FPU contexts.
 474          */
 475         prev->usersp = percpu_read(old_rsp);
 476         percpu_write(old_rsp, next->usersp);
 477         percpu_write(current_task, next_p);
 478
 479         percpu_write(kernel_stack,
 480                   (unsigned long)task_stack_page(next_p) +
 481                   THREAD_SIZE - KERNEL_STACK_OFFSET);
 482
 483         /*
 484          * Now maybe reload the debug registers and handle I/O bitmaps
 485          */
 486         if (unlikely(task_thread_info(next_p)->flags & _TIF_WORK_CTXSW_NEXT ||
 487                      task_thread_info(prev_p)->flags & _TIF_WORK_CTXSW_PREV))
 488                 __switch_to_xtra(prev_p, next_p, tss);
 489
 490         /*
 491          * Preload the FPU context, now that we've determined that the
 492          * task is likely to be using it.
 493          */
 494         if (preload_fpu)
 495                 __math_state_restore();
 496
 497         return prev_p;
 498 }
 499
 500 void set_personality_64bit(void)
 501 {
 502         /* inherit personality from parent */
 503
 504         /* Make sure to be in 64bit mode */
 505         clear_thread_flag(TIF_IA32);
 506
 507         /* Ensure the corresponding mm is not marked. */
 508         if (current->mm)
 509                 current->mm->context.ia32_compat = 0;
 510
 511         /* TBD: overwrites user setup. Should have two bits.
 512            But 64bit processes have always behaved this way,
 513            so it's not too bad. The main problem is just that
 514            32bit childs are affected again. */
 515         current->personality &= ~READ_IMPLIES_EXEC;
 516 }
 517
 518 void set_personality_ia32(void)
 519 {
 520         /* inherit personality from parent */
 521
 522         /* Make sure to be in 32bit mode */
 523         set_thread_flag(TIF_IA32);
 524         current->personality |= force_personality32;
 525
 526         /* Mark the associated mm as containing 32-bit tasks. */
 527         if (current->mm)
 528                 current->mm->context.ia32_compat = 1;
 529
 530         /* Prepare the first "return" to user space */
 531         current_thread_info()->status |= TS_COMPAT;
 532 }
 533
 534 unsigned long get_wchan(struct task_struct *p)
 535 {
 536         unsigned long stack;
 537         u64 fp, ip;
 538         int count = 0;
 539
 540         if (!p || p == current || p->state == TASK_RUNNING)
 541                 return 0;
 542         stack = (unsigned long)task_stack_page(p);
 543         if (p->thread.sp < stack || p->thread.sp >= stack+THREAD_SIZE)
 544                 return 0;
 545         fp = *(u64 *)(p->thread.sp);
 546         do {
 547                 if (fp < (unsigned long)stack ||
 548                     fp >= (unsigned long)stack+THREAD_SIZE)
 549                         return 0;
 550                 ip = *(u64 *)(fp+8);
 551                 if (!in_sched_functions(ip))
 552                         return ip;
 553                 fp = *(u64 *)fp;
 554         } while (count++ < 16);
 555         return 0;
 556 }
 557
 558 long do_arch_prctl(struct task_struct *task, int code, unsigned long addr)
 559 {
 560         int ret = 0;
 561         int doit = task == current;
 562         int cpu;
 563
 564         switch (code) {
 565         case ARCH_SET_GS:
 566                 if (addr >= TASK_SIZE_OF(task))
 567                         return -EPERM;
 568                 cpu = get_cpu();
 569                 /* handle small bases via the GDT because that's faster to
 570                    switch. */
 571                 if (addr <= 0xffffffff) {
 572                         set_32bit_tls(task, GS_TLS, addr);
 573                         if (doit) {
 574                                 load_TLS(&task->thread, cpu);
 575                                 load_gs_index(GS_TLS_SEL);
 576                         }
 577                         task->thread.gsindex = GS_TLS_SEL;
 578                         task->thread.gs = 0;
 579                 } else {
 580                         task->thread.gsindex = 0;
 581                         task->thread.gs = addr;
 582                         if (doit) {
 583                                 load_gs_index(0);
 584                                 ret = checking_wrmsrl(MSR_KERNEL_GS_BASE, addr);
 585                         }
 586                 }
 587                 put_cpu();
 588                 break;
 589         case ARCH_SET_FS:
 590                 /* Not strictly needed for fs, but do it for symmetry
 591                    with gs */
 592                 if (addr >= TASK_SIZE_OF(task))
 593                         return -EPERM;
 594                 cpu = get_cpu();
 595                 /* handle small bases via the GDT because that's faster to
 596                    switch. */
 597                 if (addr <= 0xffffffff) {
 598                         set_32bit_tls(task, FS_TLS, addr);
 599                         if (doit) {
 600                                 load_TLS(&task->thread, cpu);
 601                                 loadsegment(fs, FS_TLS_SEL);
 602                         }
 603                         task->thread.fsindex = FS_TLS_SEL;
 604                         task->thread.fs = 0;
 605                 } else {
 606                         task->thread.fsindex = 0;
 607                         task->thread.fs = addr;
 608                         if (doit) {
 609                                 /* set the selector to 0 to not confuse
 610                                    __switch_to */
 611                                 loadsegment(fs, 0);
 612                                 ret = checking_wrmsrl(MSR_FS_BASE, addr);
 613                         }
 614                 }
 615                 put_cpu();
 616                 break;
 617         case ARCH_GET_FS: {
 618                 unsigned long base;
 619                 if (task->thread.fsindex == FS_TLS_SEL)
 620                         base = read_32bit_tls(task, FS_TLS);
 621                 else if (doit)
 622                         rdmsrl(MSR_FS_BASE, base);
 623                 else
 624                         base = task->thread.fs;
 625                 ret = put_user(base, (unsigned long __user *)addr);
 626                 break;
 627         }
 628         case ARCH_GET_GS: {
 629                 unsigned long base;
 630                 unsigned gsindex;
 631                 if (task->thread.gsindex == GS_TLS_SEL)
 632                         base = read_32bit_tls(task, GS_TLS);
 633                 else if (doit) {
 634                         savesegment(gs, gsindex);
 635                         if (gsindex)
 636                                 rdmsrl(MSR_KERNEL_GS_BASE, base);
 637                         else
 638                                 base = task->thread.gs;
 639                 } else
 640                         base = task->thread.gs;
 641                 ret = put_user(base, (unsigned long __user *)addr);
 642                 break;
 643         }
 644
 645         default:
 646                 ret = -EINVAL;
 647                 break;
 648         }
 649
 650         return ret;
 651 }
 652
 653 long sys_arch_prctl(int code, unsigned long addr)
 654 {
 655         return do_arch_prctl(current, code, addr);
 656 }
 657
 658 unsigned long KSTK_ESP(struct task_struct *task)
 659 {
 660         return (test_tsk_thread_flag(task, TIF_IA32)) ?
 661                         (task_pt_regs(task)->sp) : ((task)->thread.usersp);
 662 }