2 * Derived from "arch/i386/kernel/process.c"
3 * Copyright (C) 1995 Linus Torvalds
5 * Updated and modified by Cort Dougan (cort@cs.nmt.edu) and
6 * Paul Mackerras (paulus@cs.anu.edu.au)
9 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
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.
17 #include <linux/errno.h>
18 #include <linux/sched.h>
19 #include <linux/kernel.h>
21 #include <linux/smp.h>
22 #include <linux/stddef.h>
23 #include <linux/unistd.h>
24 #include <linux/ptrace.h>
25 #include <linux/slab.h>
26 #include <linux/user.h>
27 #include <linux/elf.h>
28 #include <linux/init.h>
29 #include <linux/prctl.h>
30 #include <linux/init_task.h>
31 #include <linux/module.h>
32 #include <linux/kallsyms.h>
33 #include <linux/mqueue.h>
34 #include <linux/hardirq.h>
35 #include <linux/utsname.h>
37 #include <asm/pgtable.h>
38 #include <asm/uaccess.h>
39 #include <asm/system.h>
41 #include <asm/processor.h>
44 #include <asm/machdep.h>
46 #include <asm/syscalls.h>
48 #include <asm/firmware.h>
50 #include <linux/kprobes.h>
51 #include <linux/kdebug.h>
53 extern unsigned long _get_SP(void);
56 struct task_struct *last_task_used_math = NULL;
57 struct task_struct *last_task_used_altivec = NULL;
58 struct task_struct *last_task_used_vsx = NULL;
59 struct task_struct *last_task_used_spe = NULL;
63 * Make sure the floating-point register state in the
64 * the thread_struct is up to date for task tsk.
66 void flush_fp_to_thread(struct task_struct *tsk)
68 if (tsk->thread.regs) {
70 * We need to disable preemption here because if we didn't,
71 * another process could get scheduled after the regs->msr
72 * test but before we have finished saving the FP registers
73 * to the thread_struct. That process could take over the
74 * FPU, and then when we get scheduled again we would store
75 * bogus values for the remaining FP registers.
78 if (tsk->thread.regs->msr & MSR_FP) {
81 * This should only ever be called for current or
82 * for a stopped child process. Since we save away
83 * the FP register state on context switch on SMP,
84 * there is something wrong if a stopped child appears
85 * to still have its FP state in the CPU registers.
87 BUG_ON(tsk != current);
95 void enable_kernel_fp(void)
97 WARN_ON(preemptible());
100 if (current->thread.regs && (current->thread.regs->msr & MSR_FP))
103 giveup_fpu(NULL); /* just enables FP for kernel */
105 giveup_fpu(last_task_used_math);
106 #endif /* CONFIG_SMP */
108 EXPORT_SYMBOL(enable_kernel_fp);
110 #ifdef CONFIG_ALTIVEC
111 void enable_kernel_altivec(void)
113 WARN_ON(preemptible());
116 if (current->thread.regs && (current->thread.regs->msr & MSR_VEC))
117 giveup_altivec(current);
119 giveup_altivec(NULL); /* just enable AltiVec for kernel - force */
121 giveup_altivec(last_task_used_altivec);
122 #endif /* CONFIG_SMP */
124 EXPORT_SYMBOL(enable_kernel_altivec);
127 * Make sure the VMX/Altivec register state in the
128 * the thread_struct is up to date for task tsk.
130 void flush_altivec_to_thread(struct task_struct *tsk)
132 if (tsk->thread.regs) {
134 if (tsk->thread.regs->msr & MSR_VEC) {
136 BUG_ON(tsk != current);
143 #endif /* CONFIG_ALTIVEC */
147 /* not currently used, but some crazy RAID module might want to later */
148 void enable_kernel_vsx(void)
150 WARN_ON(preemptible());
153 if (current->thread.regs && (current->thread.regs->msr & MSR_VSX))
156 giveup_vsx(NULL); /* just enable vsx for kernel - force */
158 giveup_vsx(last_task_used_vsx);
159 #endif /* CONFIG_SMP */
161 EXPORT_SYMBOL(enable_kernel_vsx);
164 void giveup_vsx(struct task_struct *tsk)
171 void flush_vsx_to_thread(struct task_struct *tsk)
173 if (tsk->thread.regs) {
175 if (tsk->thread.regs->msr & MSR_VSX) {
177 BUG_ON(tsk != current);
184 #endif /* CONFIG_VSX */
188 void enable_kernel_spe(void)
190 WARN_ON(preemptible());
193 if (current->thread.regs && (current->thread.regs->msr & MSR_SPE))
196 giveup_spe(NULL); /* just enable SPE for kernel - force */
198 giveup_spe(last_task_used_spe);
199 #endif /* __SMP __ */
201 EXPORT_SYMBOL(enable_kernel_spe);
203 void flush_spe_to_thread(struct task_struct *tsk)
205 if (tsk->thread.regs) {
207 if (tsk->thread.regs->msr & MSR_SPE) {
209 BUG_ON(tsk != current);
216 #endif /* CONFIG_SPE */
220 * If we are doing lazy switching of CPU state (FP, altivec or SPE),
221 * and the current task has some state, discard it.
223 void discard_lazy_cpu_state(void)
226 if (last_task_used_math == current)
227 last_task_used_math = NULL;
228 #ifdef CONFIG_ALTIVEC
229 if (last_task_used_altivec == current)
230 last_task_used_altivec = NULL;
231 #endif /* CONFIG_ALTIVEC */
233 if (last_task_used_vsx == current)
234 last_task_used_vsx = NULL;
235 #endif /* CONFIG_VSX */
237 if (last_task_used_spe == current)
238 last_task_used_spe = NULL;
242 #endif /* CONFIG_SMP */
244 void do_dabr(struct pt_regs *regs, unsigned long address,
245 unsigned long error_code)
249 if (notify_die(DIE_DABR_MATCH, "dabr_match", regs, error_code,
250 11, SIGSEGV) == NOTIFY_STOP)
253 if (debugger_dabr_match(regs))
256 /* Clear the DAC and struct entries. One shot trigger */
257 #if defined(CONFIG_BOOKE)
258 mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) & ~(DBSR_DAC1R | DBSR_DAC1W
265 /* Deliver the signal to userspace */
266 info.si_signo = SIGTRAP;
268 info.si_code = TRAP_HWBKPT;
269 info.si_addr = (void __user *)address;
270 force_sig_info(SIGTRAP, &info, current);
273 static DEFINE_PER_CPU(unsigned long, current_dabr);
275 int set_dabr(unsigned long dabr)
277 __get_cpu_var(current_dabr) = dabr;
279 #ifdef CONFIG_PPC_MERGE /* XXX for now */
281 return ppc_md.set_dabr(dabr);
284 /* XXX should we have a CPU_FTR_HAS_DABR ? */
285 #if defined(CONFIG_PPC64) || defined(CONFIG_6xx)
286 mtspr(SPRN_DABR, dabr);
289 #if defined(CONFIG_BOOKE)
290 mtspr(SPRN_DAC1, dabr);
297 DEFINE_PER_CPU(struct cpu_usage, cpu_usage_array);
300 struct task_struct *__switch_to(struct task_struct *prev,
301 struct task_struct *new)
303 struct thread_struct *new_thread, *old_thread;
305 struct task_struct *last;
308 /* avoid complexity of lazy save/restore of fpu
309 * by just saving it every time we switch out if
310 * this task used the fpu during the last quantum.
312 * If it tries to use the fpu again, it'll trap and
313 * reload its fp regs. So we don't have to do a restore
314 * every switch, just a save.
317 if (prev->thread.regs && (prev->thread.regs->msr & MSR_FP))
319 #ifdef CONFIG_ALTIVEC
321 * If the previous thread used altivec in the last quantum
322 * (thus changing altivec regs) then save them.
323 * We used to check the VRSAVE register but not all apps
324 * set it, so we don't rely on it now (and in fact we need
325 * to save & restore VSCR even if VRSAVE == 0). -- paulus
327 * On SMP we always save/restore altivec regs just to avoid the
328 * complexity of changing processors.
331 if (prev->thread.regs && (prev->thread.regs->msr & MSR_VEC))
332 giveup_altivec(prev);
333 #endif /* CONFIG_ALTIVEC */
335 if (prev->thread.regs && (prev->thread.regs->msr & MSR_VSX))
336 /* VMX and FPU registers are already save here */
338 #endif /* CONFIG_VSX */
341 * If the previous thread used spe in the last quantum
342 * (thus changing spe regs) then save them.
344 * On SMP we always save/restore spe regs just to avoid the
345 * complexity of changing processors.
347 if ((prev->thread.regs && (prev->thread.regs->msr & MSR_SPE)))
349 #endif /* CONFIG_SPE */
351 #else /* CONFIG_SMP */
352 #ifdef CONFIG_ALTIVEC
353 /* Avoid the trap. On smp this this never happens since
354 * we don't set last_task_used_altivec -- Cort
356 if (new->thread.regs && last_task_used_altivec == new)
357 new->thread.regs->msr |= MSR_VEC;
358 #endif /* CONFIG_ALTIVEC */
360 if (new->thread.regs && last_task_used_vsx == new)
361 new->thread.regs->msr |= MSR_VSX;
362 #endif /* CONFIG_VSX */
364 /* Avoid the trap. On smp this this never happens since
365 * we don't set last_task_used_spe
367 if (new->thread.regs && last_task_used_spe == new)
368 new->thread.regs->msr |= MSR_SPE;
369 #endif /* CONFIG_SPE */
371 #endif /* CONFIG_SMP */
373 if (unlikely(__get_cpu_var(current_dabr) != new->thread.dabr))
374 set_dabr(new->thread.dabr);
376 #if defined(CONFIG_BOOKE)
377 /* If new thread DAC (HW breakpoint) is the same then leave it */
378 if (new->thread.dabr)
379 set_dabr(new->thread.dabr);
382 new_thread = &new->thread;
383 old_thread = ¤t->thread;
387 * Collect processor utilization data per process
389 if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
390 struct cpu_usage *cu = &__get_cpu_var(cpu_usage_array);
391 long unsigned start_tb, current_tb;
392 start_tb = old_thread->start_tb;
393 cu->current_tb = current_tb = mfspr(SPRN_PURR);
394 old_thread->accum_tb += (current_tb - start_tb);
395 new_thread->start_tb = current_tb;
399 local_irq_save(flags);
401 account_system_vtime(current);
402 account_process_vtime(current);
403 calculate_steal_time();
406 * We can't take a PMU exception inside _switch() since there is a
407 * window where the kernel stack SLB and the kernel stack are out
408 * of sync. Hard disable here.
411 last = _switch(old_thread, new_thread);
413 local_irq_restore(flags);
418 static int instructions_to_print = 16;
420 static void show_instructions(struct pt_regs *regs)
423 unsigned long pc = regs->nip - (instructions_to_print * 3 / 4 *
426 printk("Instruction dump:");
428 for (i = 0; i < instructions_to_print; i++) {
434 #if !defined(CONFIG_BOOKE)
435 /* If executing with the IMMU off, adjust pc rather
436 * than print XXXXXXXX.
438 if (!(regs->msr & MSR_IR))
439 pc = (unsigned long)phys_to_virt(pc);
442 /* We use __get_user here *only* to avoid an OOPS on a
443 * bad address because the pc *should* only be a
446 if (!__kernel_text_address(pc) ||
447 __get_user(instr, (unsigned int __user *)pc)) {
451 printk("<%08x> ", instr);
453 printk("%08x ", instr);
462 static struct regbit {
477 static void printbits(unsigned long val, struct regbit *bits)
479 const char *sep = "";
482 for (; bits->bit; ++bits)
483 if (val & bits->bit) {
484 printk("%s%s", sep, bits->name);
492 #define REGS_PER_LINE 4
493 #define LAST_VOLATILE 13
496 #define REGS_PER_LINE 8
497 #define LAST_VOLATILE 12
500 void show_regs(struct pt_regs * regs)
504 printk("NIP: "REG" LR: "REG" CTR: "REG"\n",
505 regs->nip, regs->link, regs->ctr);
506 printk("REGS: %p TRAP: %04lx %s (%s)\n",
507 regs, regs->trap, print_tainted(), init_utsname()->release);
508 printk("MSR: "REG" ", regs->msr);
509 printbits(regs->msr, msr_bits);
510 printk(" CR: %08lx XER: %08lx\n", regs->ccr, regs->xer);
512 if (trap == 0x300 || trap == 0x600)
513 #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
514 printk("DEAR: "REG", ESR: "REG"\n", regs->dar, regs->dsisr);
516 printk("DAR: "REG", DSISR: "REG"\n", regs->dar, regs->dsisr);
518 printk("TASK = %p[%d] '%s' THREAD: %p",
519 current, task_pid_nr(current), current->comm, task_thread_info(current));
522 printk(" CPU: %d", raw_smp_processor_id());
523 #endif /* CONFIG_SMP */
525 for (i = 0; i < 32; i++) {
526 if ((i % REGS_PER_LINE) == 0)
527 printk("\n" KERN_INFO "GPR%02d: ", i);
528 printk(REG " ", regs->gpr[i]);
529 if (i == LAST_VOLATILE && !FULL_REGS(regs))
533 #ifdef CONFIG_KALLSYMS
535 * Lookup NIP late so we have the best change of getting the
536 * above info out without failing
538 printk("NIP ["REG"] %pS\n", regs->nip, (void *)regs->nip);
539 printk("LR ["REG"] %pS\n", regs->link, (void *)regs->link);
541 show_stack(current, (unsigned long *) regs->gpr[1]);
542 if (!user_mode(regs))
543 show_instructions(regs);
546 void exit_thread(void)
548 discard_lazy_cpu_state();
551 void flush_thread(void)
554 struct thread_info *t = current_thread_info();
556 if (test_ti_thread_flag(t, TIF_ABI_PENDING)) {
557 clear_ti_thread_flag(t, TIF_ABI_PENDING);
558 if (test_ti_thread_flag(t, TIF_32BIT))
559 clear_ti_thread_flag(t, TIF_32BIT);
561 set_ti_thread_flag(t, TIF_32BIT);
565 discard_lazy_cpu_state();
567 if (current->thread.dabr) {
568 current->thread.dabr = 0;
571 #if defined(CONFIG_BOOKE)
572 current->thread.dbcr0 &= ~(DBSR_DAC1R | DBSR_DAC1W);
578 release_thread(struct task_struct *t)
583 * This gets called before we allocate a new thread and copy
584 * the current task into it.
586 void prepare_to_copy(struct task_struct *tsk)
588 flush_fp_to_thread(current);
589 flush_altivec_to_thread(current);
590 flush_vsx_to_thread(current);
591 flush_spe_to_thread(current);
597 int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
598 unsigned long unused, struct task_struct *p,
599 struct pt_regs *regs)
601 struct pt_regs *childregs, *kregs;
602 extern void ret_from_fork(void);
603 unsigned long sp = (unsigned long)task_stack_page(p) + THREAD_SIZE;
605 CHECK_FULL_REGS(regs);
607 sp -= sizeof(struct pt_regs);
608 childregs = (struct pt_regs *) sp;
610 if ((childregs->msr & MSR_PR) == 0) {
611 /* for kernel thread, set `current' and stackptr in new task */
612 childregs->gpr[1] = sp + sizeof(struct pt_regs);
614 childregs->gpr[2] = (unsigned long) p;
616 clear_tsk_thread_flag(p, TIF_32BIT);
618 p->thread.regs = NULL; /* no user register state */
620 childregs->gpr[1] = usp;
621 p->thread.regs = childregs;
622 if (clone_flags & CLONE_SETTLS) {
624 if (!test_thread_flag(TIF_32BIT))
625 childregs->gpr[13] = childregs->gpr[6];
628 childregs->gpr[2] = childregs->gpr[6];
631 childregs->gpr[3] = 0; /* Result from fork() */
632 sp -= STACK_FRAME_OVERHEAD;
635 * The way this works is that at some point in the future
636 * some task will call _switch to switch to the new task.
637 * That will pop off the stack frame created below and start
638 * the new task running at ret_from_fork. The new task will
639 * do some house keeping and then return from the fork or clone
640 * system call, using the stack frame created above.
642 sp -= sizeof(struct pt_regs);
643 kregs = (struct pt_regs *) sp;
644 sp -= STACK_FRAME_OVERHEAD;
646 p->thread.ksp_limit = (unsigned long)task_stack_page(p) +
647 _ALIGN_UP(sizeof(struct thread_info), 16);
650 if (cpu_has_feature(CPU_FTR_SLB)) {
651 unsigned long sp_vsid;
652 unsigned long llp = mmu_psize_defs[mmu_linear_psize].sllp;
654 if (cpu_has_feature(CPU_FTR_1T_SEGMENT))
655 sp_vsid = get_kernel_vsid(sp, MMU_SEGSIZE_1T)
656 << SLB_VSID_SHIFT_1T;
658 sp_vsid = get_kernel_vsid(sp, MMU_SEGSIZE_256M)
660 sp_vsid |= SLB_VSID_KERNEL | llp;
661 p->thread.ksp_vsid = sp_vsid;
665 * The PPC64 ABI makes use of a TOC to contain function
666 * pointers. The function (ret_from_except) is actually a pointer
667 * to the TOC entry. The first entry is a pointer to the actual
670 kregs->nip = *((unsigned long *)ret_from_fork);
672 kregs->nip = (unsigned long)ret_from_fork;
679 * Set up a thread for executing a new program
681 void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
684 unsigned long load_addr = regs->gpr[2]; /* saved by ELF_PLAT_INIT */
690 * If we exec out of a kernel thread then thread.regs will not be
693 if (!current->thread.regs) {
694 struct pt_regs *regs = task_stack_page(current) + THREAD_SIZE;
695 current->thread.regs = regs - 1;
698 memset(regs->gpr, 0, sizeof(regs->gpr));
706 * We have just cleared all the nonvolatile GPRs, so make
707 * FULL_REGS(regs) return true. This is necessary to allow
708 * ptrace to examine the thread immediately after exec.
715 regs->msr = MSR_USER;
717 if (!test_thread_flag(TIF_32BIT)) {
718 unsigned long entry, toc;
720 /* start is a relocated pointer to the function descriptor for
721 * the elf _start routine. The first entry in the function
722 * descriptor is the entry address of _start and the second
723 * entry is the TOC value we need to use.
725 __get_user(entry, (unsigned long __user *)start);
726 __get_user(toc, (unsigned long __user *)start+1);
728 /* Check whether the e_entry function descriptor entries
729 * need to be relocated before we can use them.
731 if (load_addr != 0) {
737 regs->msr = MSR_USER64;
741 regs->msr = MSR_USER32;
745 discard_lazy_cpu_state();
747 current->thread.used_vsr = 0;
749 memset(current->thread.fpr, 0, sizeof(current->thread.fpr));
750 current->thread.fpscr.val = 0;
751 #ifdef CONFIG_ALTIVEC
752 memset(current->thread.vr, 0, sizeof(current->thread.vr));
753 memset(¤t->thread.vscr, 0, sizeof(current->thread.vscr));
754 current->thread.vscr.u[3] = 0x00010000; /* Java mode disabled */
755 current->thread.vrsave = 0;
756 current->thread.used_vr = 0;
757 #endif /* CONFIG_ALTIVEC */
759 memset(current->thread.evr, 0, sizeof(current->thread.evr));
760 current->thread.acc = 0;
761 current->thread.spefscr = 0;
762 current->thread.used_spe = 0;
763 #endif /* CONFIG_SPE */
766 #define PR_FP_ALL_EXCEPT (PR_FP_EXC_DIV | PR_FP_EXC_OVF | PR_FP_EXC_UND \
767 | PR_FP_EXC_RES | PR_FP_EXC_INV)
769 int set_fpexc_mode(struct task_struct *tsk, unsigned int val)
771 struct pt_regs *regs = tsk->thread.regs;
773 /* This is a bit hairy. If we are an SPE enabled processor
774 * (have embedded fp) we store the IEEE exception enable flags in
775 * fpexc_mode. fpexc_mode is also used for setting FP exception
776 * mode (asyn, precise, disabled) for 'Classic' FP. */
777 if (val & PR_FP_EXC_SW_ENABLE) {
779 if (cpu_has_feature(CPU_FTR_SPE)) {
780 tsk->thread.fpexc_mode = val &
781 (PR_FP_EXC_SW_ENABLE | PR_FP_ALL_EXCEPT);
791 /* on a CONFIG_SPE this does not hurt us. The bits that
792 * __pack_fe01 use do not overlap with bits used for
793 * PR_FP_EXC_SW_ENABLE. Additionally, the MSR[FE0,FE1] bits
794 * on CONFIG_SPE implementations are reserved so writing to
795 * them does not change anything */
796 if (val > PR_FP_EXC_PRECISE)
798 tsk->thread.fpexc_mode = __pack_fe01(val);
799 if (regs != NULL && (regs->msr & MSR_FP) != 0)
800 regs->msr = (regs->msr & ~(MSR_FE0|MSR_FE1))
801 | tsk->thread.fpexc_mode;
805 int get_fpexc_mode(struct task_struct *tsk, unsigned long adr)
809 if (tsk->thread.fpexc_mode & PR_FP_EXC_SW_ENABLE)
811 if (cpu_has_feature(CPU_FTR_SPE))
812 val = tsk->thread.fpexc_mode;
819 val = __unpack_fe01(tsk->thread.fpexc_mode);
820 return put_user(val, (unsigned int __user *) adr);
823 int set_endian(struct task_struct *tsk, unsigned int val)
825 struct pt_regs *regs = tsk->thread.regs;
827 if ((val == PR_ENDIAN_LITTLE && !cpu_has_feature(CPU_FTR_REAL_LE)) ||
828 (val == PR_ENDIAN_PPC_LITTLE && !cpu_has_feature(CPU_FTR_PPC_LE)))
834 if (val == PR_ENDIAN_BIG)
835 regs->msr &= ~MSR_LE;
836 else if (val == PR_ENDIAN_LITTLE || val == PR_ENDIAN_PPC_LITTLE)
844 int get_endian(struct task_struct *tsk, unsigned long adr)
846 struct pt_regs *regs = tsk->thread.regs;
849 if (!cpu_has_feature(CPU_FTR_PPC_LE) &&
850 !cpu_has_feature(CPU_FTR_REAL_LE))
856 if (regs->msr & MSR_LE) {
857 if (cpu_has_feature(CPU_FTR_REAL_LE))
858 val = PR_ENDIAN_LITTLE;
860 val = PR_ENDIAN_PPC_LITTLE;
864 return put_user(val, (unsigned int __user *)adr);
867 int set_unalign_ctl(struct task_struct *tsk, unsigned int val)
869 tsk->thread.align_ctl = val;
873 int get_unalign_ctl(struct task_struct *tsk, unsigned long adr)
875 return put_user(tsk->thread.align_ctl, (unsigned int __user *)adr);
878 #define TRUNC_PTR(x) ((typeof(x))(((unsigned long)(x)) & 0xffffffff))
880 int sys_clone(unsigned long clone_flags, unsigned long usp,
881 int __user *parent_tidp, void __user *child_threadptr,
882 int __user *child_tidp, int p6,
883 struct pt_regs *regs)
885 CHECK_FULL_REGS(regs);
887 usp = regs->gpr[1]; /* stack pointer for child */
889 if (test_thread_flag(TIF_32BIT)) {
890 parent_tidp = TRUNC_PTR(parent_tidp);
891 child_tidp = TRUNC_PTR(child_tidp);
894 return do_fork(clone_flags, usp, regs, 0, parent_tidp, child_tidp);
897 int sys_fork(unsigned long p1, unsigned long p2, unsigned long p3,
898 unsigned long p4, unsigned long p5, unsigned long p6,
899 struct pt_regs *regs)
901 CHECK_FULL_REGS(regs);
902 return do_fork(SIGCHLD, regs->gpr[1], regs, 0, NULL, NULL);
905 int sys_vfork(unsigned long p1, unsigned long p2, unsigned long p3,
906 unsigned long p4, unsigned long p5, unsigned long p6,
907 struct pt_regs *regs)
909 CHECK_FULL_REGS(regs);
910 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->gpr[1],
911 regs, 0, NULL, NULL);
914 int sys_execve(unsigned long a0, unsigned long a1, unsigned long a2,
915 unsigned long a3, unsigned long a4, unsigned long a5,
916 struct pt_regs *regs)
921 filename = getname((char __user *) a0);
922 error = PTR_ERR(filename);
923 if (IS_ERR(filename))
925 flush_fp_to_thread(current);
926 flush_altivec_to_thread(current);
927 flush_spe_to_thread(current);
928 error = do_execve(filename, (char __user * __user *) a1,
929 (char __user * __user *) a2, regs);
935 #ifdef CONFIG_IRQSTACKS
936 static inline int valid_irq_stack(unsigned long sp, struct task_struct *p,
937 unsigned long nbytes)
939 unsigned long stack_page;
940 unsigned long cpu = task_cpu(p);
943 * Avoid crashing if the stack has overflowed and corrupted
944 * task_cpu(p), which is in the thread_info struct.
946 if (cpu < NR_CPUS && cpu_possible(cpu)) {
947 stack_page = (unsigned long) hardirq_ctx[cpu];
948 if (sp >= stack_page + sizeof(struct thread_struct)
949 && sp <= stack_page + THREAD_SIZE - nbytes)
952 stack_page = (unsigned long) softirq_ctx[cpu];
953 if (sp >= stack_page + sizeof(struct thread_struct)
954 && sp <= stack_page + THREAD_SIZE - nbytes)
961 #define valid_irq_stack(sp, p, nb) 0
962 #endif /* CONFIG_IRQSTACKS */
964 int validate_sp(unsigned long sp, struct task_struct *p,
965 unsigned long nbytes)
967 unsigned long stack_page = (unsigned long)task_stack_page(p);
969 if (sp >= stack_page + sizeof(struct thread_struct)
970 && sp <= stack_page + THREAD_SIZE - nbytes)
973 return valid_irq_stack(sp, p, nbytes);
976 EXPORT_SYMBOL(validate_sp);
978 unsigned long get_wchan(struct task_struct *p)
980 unsigned long ip, sp;
983 if (!p || p == current || p->state == TASK_RUNNING)
987 if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD))
991 sp = *(unsigned long *)sp;
992 if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD))
995 ip = ((unsigned long *)sp)[STACK_FRAME_LR_SAVE];
996 if (!in_sched_functions(ip))
999 } while (count++ < 16);
1003 static int kstack_depth_to_print = 64;
1005 void show_stack(struct task_struct *tsk, unsigned long *stack)
1007 unsigned long sp, ip, lr, newsp;
1011 sp = (unsigned long) stack;
1016 asm("mr %0,1" : "=r" (sp));
1018 sp = tsk->thread.ksp;
1022 printk("Call Trace:\n");
1024 if (!validate_sp(sp, tsk, STACK_FRAME_OVERHEAD))
1027 stack = (unsigned long *) sp;
1029 ip = stack[STACK_FRAME_LR_SAVE];
1030 if (!firstframe || ip != lr) {
1031 printk("["REG"] ["REG"] %pS", sp, ip, (void *)ip);
1033 printk(" (unreliable)");
1039 * See if this is an exception frame.
1040 * We look for the "regshere" marker in the current frame.
1042 if (validate_sp(sp, tsk, STACK_INT_FRAME_SIZE)
1043 && stack[STACK_FRAME_MARKER] == STACK_FRAME_REGS_MARKER) {
1044 struct pt_regs *regs = (struct pt_regs *)
1045 (sp + STACK_FRAME_OVERHEAD);
1047 printk("--- Exception: %lx at %pS\n LR = %pS\n",
1048 regs->trap, (void *)regs->nip, (void *)lr);
1053 } while (count++ < kstack_depth_to_print);
1056 void dump_stack(void)
1058 show_stack(current, NULL);
1060 EXPORT_SYMBOL(dump_stack);
1063 void ppc64_runlatch_on(void)
1067 if (cpu_has_feature(CPU_FTR_CTRL) && !test_thread_flag(TIF_RUNLATCH)) {
1070 ctrl = mfspr(SPRN_CTRLF);
1071 ctrl |= CTRL_RUNLATCH;
1072 mtspr(SPRN_CTRLT, ctrl);
1074 set_thread_flag(TIF_RUNLATCH);
1078 void ppc64_runlatch_off(void)
1082 if (cpu_has_feature(CPU_FTR_CTRL) && test_thread_flag(TIF_RUNLATCH)) {
1085 clear_thread_flag(TIF_RUNLATCH);
1087 ctrl = mfspr(SPRN_CTRLF);
1088 ctrl &= ~CTRL_RUNLATCH;
1089 mtspr(SPRN_CTRLT, ctrl);
1094 #if THREAD_SHIFT < PAGE_SHIFT
1096 static struct kmem_cache *thread_info_cache;
1098 struct thread_info *alloc_thread_info(struct task_struct *tsk)
1100 struct thread_info *ti;
1102 ti = kmem_cache_alloc(thread_info_cache, GFP_KERNEL);
1103 if (unlikely(ti == NULL))
1105 #ifdef CONFIG_DEBUG_STACK_USAGE
1106 memset(ti, 0, THREAD_SIZE);
1111 void free_thread_info(struct thread_info *ti)
1113 kmem_cache_free(thread_info_cache, ti);
1116 void thread_info_cache_init(void)
1118 thread_info_cache = kmem_cache_create("thread_info", THREAD_SIZE,
1119 THREAD_SIZE, 0, NULL);
1120 BUG_ON(thread_info_cache == NULL);
1123 #endif /* THREAD_SHIFT < PAGE_SHIFT */