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>
51 extern unsigned long _get_SP(void);
54 struct task_struct
*last_task_used_math
= NULL
;
55 struct task_struct
*last_task_used_altivec
= NULL
;
56 struct task_struct
*last_task_used_spe
= NULL
;
60 * Make sure the floating-point register state in the
61 * the thread_struct is up to date for task tsk.
63 void flush_fp_to_thread(struct task_struct
*tsk
)
65 if (tsk
->thread
.regs
) {
67 * We need to disable preemption here because if we didn't,
68 * another process could get scheduled after the regs->msr
69 * test but before we have finished saving the FP registers
70 * to the thread_struct. That process could take over the
71 * FPU, and then when we get scheduled again we would store
72 * bogus values for the remaining FP registers.
75 if (tsk
->thread
.regs
->msr
& MSR_FP
) {
78 * This should only ever be called for current or
79 * for a stopped child process. Since we save away
80 * the FP register state on context switch on SMP,
81 * there is something wrong if a stopped child appears
82 * to still have its FP state in the CPU registers.
84 BUG_ON(tsk
!= current
);
92 void enable_kernel_fp(void)
94 WARN_ON(preemptible());
97 if (current
->thread
.regs
&& (current
->thread
.regs
->msr
& MSR_FP
))
100 giveup_fpu(NULL
); /* just enables FP for kernel */
102 giveup_fpu(last_task_used_math
);
103 #endif /* CONFIG_SMP */
105 EXPORT_SYMBOL(enable_kernel_fp
);
107 int dump_task_fpu(struct task_struct
*tsk
, elf_fpregset_t
*fpregs
)
109 if (!tsk
->thread
.regs
)
111 flush_fp_to_thread(current
);
113 memcpy(fpregs
, &tsk
->thread
.fpr
[0], sizeof(*fpregs
));
118 #ifdef CONFIG_ALTIVEC
119 void enable_kernel_altivec(void)
121 WARN_ON(preemptible());
124 if (current
->thread
.regs
&& (current
->thread
.regs
->msr
& MSR_VEC
))
125 giveup_altivec(current
);
127 giveup_altivec(NULL
); /* just enable AltiVec for kernel - force */
129 giveup_altivec(last_task_used_altivec
);
130 #endif /* CONFIG_SMP */
132 EXPORT_SYMBOL(enable_kernel_altivec
);
135 * Make sure the VMX/Altivec register state in the
136 * the thread_struct is up to date for task tsk.
138 void flush_altivec_to_thread(struct task_struct
*tsk
)
140 if (tsk
->thread
.regs
) {
142 if (tsk
->thread
.regs
->msr
& MSR_VEC
) {
144 BUG_ON(tsk
!= current
);
152 int dump_task_altivec(struct pt_regs
*regs
, elf_vrregset_t
*vrregs
)
154 flush_altivec_to_thread(current
);
155 memcpy(vrregs
, ¤t
->thread
.vr
[0], sizeof(*vrregs
));
158 #endif /* CONFIG_ALTIVEC */
162 void enable_kernel_spe(void)
164 WARN_ON(preemptible());
167 if (current
->thread
.regs
&& (current
->thread
.regs
->msr
& MSR_SPE
))
170 giveup_spe(NULL
); /* just enable SPE for kernel - force */
172 giveup_spe(last_task_used_spe
);
173 #endif /* __SMP __ */
175 EXPORT_SYMBOL(enable_kernel_spe
);
177 void flush_spe_to_thread(struct task_struct
*tsk
)
179 if (tsk
->thread
.regs
) {
181 if (tsk
->thread
.regs
->msr
& MSR_SPE
) {
183 BUG_ON(tsk
!= current
);
191 int dump_spe(struct pt_regs
*regs
, elf_vrregset_t
*evrregs
)
193 flush_spe_to_thread(current
);
194 /* We copy u32 evr[32] + u64 acc + u32 spefscr -> 35 */
195 memcpy(evrregs
, ¤t
->thread
.evr
[0], sizeof(u32
) * 35);
198 #endif /* CONFIG_SPE */
202 * If we are doing lazy switching of CPU state (FP, altivec or SPE),
203 * and the current task has some state, discard it.
205 void discard_lazy_cpu_state(void)
208 if (last_task_used_math
== current
)
209 last_task_used_math
= NULL
;
210 #ifdef CONFIG_ALTIVEC
211 if (last_task_used_altivec
== current
)
212 last_task_used_altivec
= NULL
;
213 #endif /* CONFIG_ALTIVEC */
215 if (last_task_used_spe
== current
)
216 last_task_used_spe
= NULL
;
220 #endif /* CONFIG_SMP */
222 int set_dabr(unsigned long dabr
)
224 #ifdef CONFIG_PPC_MERGE /* XXX for now */
226 return ppc_md
.set_dabr(dabr
);
229 /* XXX should we have a CPU_FTR_HAS_DABR ? */
230 #if defined(CONFIG_PPC64) || defined(CONFIG_6xx)
231 mtspr(SPRN_DABR
, dabr
);
237 DEFINE_PER_CPU(struct cpu_usage
, cpu_usage_array
);
240 static DEFINE_PER_CPU(unsigned long, current_dabr
);
242 struct task_struct
*__switch_to(struct task_struct
*prev
,
243 struct task_struct
*new)
245 struct thread_struct
*new_thread
, *old_thread
;
247 struct task_struct
*last
;
250 /* avoid complexity of lazy save/restore of fpu
251 * by just saving it every time we switch out if
252 * this task used the fpu during the last quantum.
254 * If it tries to use the fpu again, it'll trap and
255 * reload its fp regs. So we don't have to do a restore
256 * every switch, just a save.
259 if (prev
->thread
.regs
&& (prev
->thread
.regs
->msr
& MSR_FP
))
261 #ifdef CONFIG_ALTIVEC
263 * If the previous thread used altivec in the last quantum
264 * (thus changing altivec regs) then save them.
265 * We used to check the VRSAVE register but not all apps
266 * set it, so we don't rely on it now (and in fact we need
267 * to save & restore VSCR even if VRSAVE == 0). -- paulus
269 * On SMP we always save/restore altivec regs just to avoid the
270 * complexity of changing processors.
273 if (prev
->thread
.regs
&& (prev
->thread
.regs
->msr
& MSR_VEC
))
274 giveup_altivec(prev
);
275 #endif /* CONFIG_ALTIVEC */
278 * If the previous thread used spe in the last quantum
279 * (thus changing spe regs) then save them.
281 * On SMP we always save/restore spe regs just to avoid the
282 * complexity of changing processors.
284 if ((prev
->thread
.regs
&& (prev
->thread
.regs
->msr
& MSR_SPE
)))
286 #endif /* CONFIG_SPE */
288 #else /* CONFIG_SMP */
289 #ifdef CONFIG_ALTIVEC
290 /* Avoid the trap. On smp this this never happens since
291 * we don't set last_task_used_altivec -- Cort
293 if (new->thread
.regs
&& last_task_used_altivec
== new)
294 new->thread
.regs
->msr
|= MSR_VEC
;
295 #endif /* CONFIG_ALTIVEC */
297 /* Avoid the trap. On smp this this never happens since
298 * we don't set last_task_used_spe
300 if (new->thread
.regs
&& last_task_used_spe
== new)
301 new->thread
.regs
->msr
|= MSR_SPE
;
302 #endif /* CONFIG_SPE */
304 #endif /* CONFIG_SMP */
306 if (unlikely(__get_cpu_var(current_dabr
) != new->thread
.dabr
)) {
307 set_dabr(new->thread
.dabr
);
308 __get_cpu_var(current_dabr
) = new->thread
.dabr
;
311 new_thread
= &new->thread
;
312 old_thread
= ¤t
->thread
;
316 * Collect processor utilization data per process
318 if (firmware_has_feature(FW_FEATURE_SPLPAR
)) {
319 struct cpu_usage
*cu
= &__get_cpu_var(cpu_usage_array
);
320 long unsigned start_tb
, current_tb
;
321 start_tb
= old_thread
->start_tb
;
322 cu
->current_tb
= current_tb
= mfspr(SPRN_PURR
);
323 old_thread
->accum_tb
+= (current_tb
- start_tb
);
324 new_thread
->start_tb
= current_tb
;
328 local_irq_save(flags
);
330 account_system_vtime(current
);
331 account_process_vtime(current
);
332 calculate_steal_time();
334 last
= _switch(old_thread
, new_thread
);
336 local_irq_restore(flags
);
341 static int instructions_to_print
= 16;
343 static void show_instructions(struct pt_regs
*regs
)
346 unsigned long pc
= regs
->nip
- (instructions_to_print
* 3 / 4 *
349 printk("Instruction dump:");
351 for (i
= 0; i
< instructions_to_print
; i
++) {
357 #if !defined(CONFIG_BOOKE)
358 /* If executing with the IMMU off, adjust pc rather
359 * than print XXXXXXXX.
361 if (!(regs
->msr
& MSR_IR
))
362 pc
= (unsigned long)phys_to_virt(pc
);
365 /* We use __get_user here *only* to avoid an OOPS on a
366 * bad address because the pc *should* only be a
369 if (!__kernel_text_address(pc
) ||
370 __get_user(instr
, (unsigned int __user
*)pc
)) {
374 printk("<%08x> ", instr
);
376 printk("%08x ", instr
);
385 static struct regbit
{
398 static void printbits(unsigned long val
, struct regbit
*bits
)
400 const char *sep
= "";
403 for (; bits
->bit
; ++bits
)
404 if (val
& bits
->bit
) {
405 printk("%s%s", sep
, bits
->name
);
413 #define REGS_PER_LINE 4
414 #define LAST_VOLATILE 13
417 #define REGS_PER_LINE 8
418 #define LAST_VOLATILE 12
421 void show_regs(struct pt_regs
* regs
)
425 printk("NIP: "REG
" LR: "REG
" CTR: "REG
"\n",
426 regs
->nip
, regs
->link
, regs
->ctr
);
427 printk("REGS: %p TRAP: %04lx %s (%s)\n",
428 regs
, regs
->trap
, print_tainted(), init_utsname()->release
);
429 printk("MSR: "REG
" ", regs
->msr
);
430 printbits(regs
->msr
, msr_bits
);
431 printk(" CR: %08lx XER: %08lx\n", regs
->ccr
, regs
->xer
);
433 if (trap
== 0x300 || trap
== 0x600)
434 #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
435 printk("DEAR: "REG
", ESR: "REG
"\n", regs
->dar
, regs
->dsisr
);
437 printk("DAR: "REG
", DSISR: "REG
"\n", regs
->dar
, regs
->dsisr
);
439 printk("TASK = %p[%d] '%s' THREAD: %p",
440 current
, current
->pid
, current
->comm
, task_thread_info(current
));
443 printk(" CPU: %d", smp_processor_id());
444 #endif /* CONFIG_SMP */
446 for (i
= 0; i
< 32; i
++) {
447 if ((i
% REGS_PER_LINE
) == 0)
448 printk("\n" KERN_INFO
"GPR%02d: ", i
);
449 printk(REG
" ", regs
->gpr
[i
]);
450 if (i
== LAST_VOLATILE
&& !FULL_REGS(regs
))
454 #ifdef CONFIG_KALLSYMS
456 * Lookup NIP late so we have the best change of getting the
457 * above info out without failing
459 printk("NIP ["REG
"] ", regs
->nip
);
460 print_symbol("%s\n", regs
->nip
);
461 printk("LR ["REG
"] ", regs
->link
);
462 print_symbol("%s\n", regs
->link
);
464 show_stack(current
, (unsigned long *) regs
->gpr
[1]);
465 if (!user_mode(regs
))
466 show_instructions(regs
);
469 void exit_thread(void)
471 discard_lazy_cpu_state();
474 void flush_thread(void)
477 struct thread_info
*t
= current_thread_info();
479 if (test_ti_thread_flag(t
, TIF_ABI_PENDING
)) {
480 clear_ti_thread_flag(t
, TIF_ABI_PENDING
);
481 if (test_ti_thread_flag(t
, TIF_32BIT
))
482 clear_ti_thread_flag(t
, TIF_32BIT
);
484 set_ti_thread_flag(t
, TIF_32BIT
);
488 discard_lazy_cpu_state();
490 if (current
->thread
.dabr
) {
491 current
->thread
.dabr
= 0;
497 release_thread(struct task_struct
*t
)
502 * This gets called before we allocate a new thread and copy
503 * the current task into it.
505 void prepare_to_copy(struct task_struct
*tsk
)
507 flush_fp_to_thread(current
);
508 flush_altivec_to_thread(current
);
509 flush_spe_to_thread(current
);
515 int copy_thread(int nr
, unsigned long clone_flags
, unsigned long usp
,
516 unsigned long unused
, struct task_struct
*p
,
517 struct pt_regs
*regs
)
519 struct pt_regs
*childregs
, *kregs
;
520 extern void ret_from_fork(void);
521 unsigned long sp
= (unsigned long)task_stack_page(p
) + THREAD_SIZE
;
523 CHECK_FULL_REGS(regs
);
525 sp
-= sizeof(struct pt_regs
);
526 childregs
= (struct pt_regs
*) sp
;
528 if ((childregs
->msr
& MSR_PR
) == 0) {
529 /* for kernel thread, set `current' and stackptr in new task */
530 childregs
->gpr
[1] = sp
+ sizeof(struct pt_regs
);
532 childregs
->gpr
[2] = (unsigned long) p
;
534 clear_tsk_thread_flag(p
, TIF_32BIT
);
536 p
->thread
.regs
= NULL
; /* no user register state */
538 childregs
->gpr
[1] = usp
;
539 p
->thread
.regs
= childregs
;
540 if (clone_flags
& CLONE_SETTLS
) {
542 if (!test_thread_flag(TIF_32BIT
))
543 childregs
->gpr
[13] = childregs
->gpr
[6];
546 childregs
->gpr
[2] = childregs
->gpr
[6];
549 childregs
->gpr
[3] = 0; /* Result from fork() */
550 sp
-= STACK_FRAME_OVERHEAD
;
553 * The way this works is that at some point in the future
554 * some task will call _switch to switch to the new task.
555 * That will pop off the stack frame created below and start
556 * the new task running at ret_from_fork. The new task will
557 * do some house keeping and then return from the fork or clone
558 * system call, using the stack frame created above.
560 sp
-= sizeof(struct pt_regs
);
561 kregs
= (struct pt_regs
*) sp
;
562 sp
-= STACK_FRAME_OVERHEAD
;
566 if (cpu_has_feature(CPU_FTR_SLB
)) {
567 unsigned long sp_vsid
= get_kernel_vsid(sp
);
568 unsigned long llp
= mmu_psize_defs
[mmu_linear_psize
].sllp
;
570 sp_vsid
<<= SLB_VSID_SHIFT
;
571 sp_vsid
|= SLB_VSID_KERNEL
| llp
;
572 p
->thread
.ksp_vsid
= sp_vsid
;
576 * The PPC64 ABI makes use of a TOC to contain function
577 * pointers. The function (ret_from_except) is actually a pointer
578 * to the TOC entry. The first entry is a pointer to the actual
581 kregs
->nip
= *((unsigned long *)ret_from_fork
);
583 kregs
->nip
= (unsigned long)ret_from_fork
;
590 * Set up a thread for executing a new program
592 void start_thread(struct pt_regs
*regs
, unsigned long start
, unsigned long sp
)
595 unsigned long load_addr
= regs
->gpr
[2]; /* saved by ELF_PLAT_INIT */
601 * If we exec out of a kernel thread then thread.regs will not be
604 if (!current
->thread
.regs
) {
605 struct pt_regs
*regs
= task_stack_page(current
) + THREAD_SIZE
;
606 current
->thread
.regs
= regs
- 1;
609 memset(regs
->gpr
, 0, sizeof(regs
->gpr
));
619 regs
->msr
= MSR_USER
;
621 if (!test_thread_flag(TIF_32BIT
)) {
622 unsigned long entry
, toc
;
624 /* start is a relocated pointer to the function descriptor for
625 * the elf _start routine. The first entry in the function
626 * descriptor is the entry address of _start and the second
627 * entry is the TOC value we need to use.
629 __get_user(entry
, (unsigned long __user
*)start
);
630 __get_user(toc
, (unsigned long __user
*)start
+1);
632 /* Check whether the e_entry function descriptor entries
633 * need to be relocated before we can use them.
635 if (load_addr
!= 0) {
641 regs
->msr
= MSR_USER64
;
645 regs
->msr
= MSR_USER32
;
649 discard_lazy_cpu_state();
650 memset(current
->thread
.fpr
, 0, sizeof(current
->thread
.fpr
));
651 current
->thread
.fpscr
.val
= 0;
652 #ifdef CONFIG_ALTIVEC
653 memset(current
->thread
.vr
, 0, sizeof(current
->thread
.vr
));
654 memset(¤t
->thread
.vscr
, 0, sizeof(current
->thread
.vscr
));
655 current
->thread
.vscr
.u
[3] = 0x00010000; /* Java mode disabled */
656 current
->thread
.vrsave
= 0;
657 current
->thread
.used_vr
= 0;
658 #endif /* CONFIG_ALTIVEC */
660 memset(current
->thread
.evr
, 0, sizeof(current
->thread
.evr
));
661 current
->thread
.acc
= 0;
662 current
->thread
.spefscr
= 0;
663 current
->thread
.used_spe
= 0;
664 #endif /* CONFIG_SPE */
667 #define PR_FP_ALL_EXCEPT (PR_FP_EXC_DIV | PR_FP_EXC_OVF | PR_FP_EXC_UND \
668 | PR_FP_EXC_RES | PR_FP_EXC_INV)
670 int set_fpexc_mode(struct task_struct
*tsk
, unsigned int val
)
672 struct pt_regs
*regs
= tsk
->thread
.regs
;
674 /* This is a bit hairy. If we are an SPE enabled processor
675 * (have embedded fp) we store the IEEE exception enable flags in
676 * fpexc_mode. fpexc_mode is also used for setting FP exception
677 * mode (asyn, precise, disabled) for 'Classic' FP. */
678 if (val
& PR_FP_EXC_SW_ENABLE
) {
680 if (cpu_has_feature(CPU_FTR_SPE
)) {
681 tsk
->thread
.fpexc_mode
= val
&
682 (PR_FP_EXC_SW_ENABLE
| PR_FP_ALL_EXCEPT
);
692 /* on a CONFIG_SPE this does not hurt us. The bits that
693 * __pack_fe01 use do not overlap with bits used for
694 * PR_FP_EXC_SW_ENABLE. Additionally, the MSR[FE0,FE1] bits
695 * on CONFIG_SPE implementations are reserved so writing to
696 * them does not change anything */
697 if (val
> PR_FP_EXC_PRECISE
)
699 tsk
->thread
.fpexc_mode
= __pack_fe01(val
);
700 if (regs
!= NULL
&& (regs
->msr
& MSR_FP
) != 0)
701 regs
->msr
= (regs
->msr
& ~(MSR_FE0
|MSR_FE1
))
702 | tsk
->thread
.fpexc_mode
;
706 int get_fpexc_mode(struct task_struct
*tsk
, unsigned long adr
)
710 if (tsk
->thread
.fpexc_mode
& PR_FP_EXC_SW_ENABLE
)
712 if (cpu_has_feature(CPU_FTR_SPE
))
713 val
= tsk
->thread
.fpexc_mode
;
720 val
= __unpack_fe01(tsk
->thread
.fpexc_mode
);
721 return put_user(val
, (unsigned int __user
*) adr
);
724 int set_endian(struct task_struct
*tsk
, unsigned int val
)
726 struct pt_regs
*regs
= tsk
->thread
.regs
;
728 if ((val
== PR_ENDIAN_LITTLE
&& !cpu_has_feature(CPU_FTR_REAL_LE
)) ||
729 (val
== PR_ENDIAN_PPC_LITTLE
&& !cpu_has_feature(CPU_FTR_PPC_LE
)))
735 if (val
== PR_ENDIAN_BIG
)
736 regs
->msr
&= ~MSR_LE
;
737 else if (val
== PR_ENDIAN_LITTLE
|| val
== PR_ENDIAN_PPC_LITTLE
)
745 int get_endian(struct task_struct
*tsk
, unsigned long adr
)
747 struct pt_regs
*regs
= tsk
->thread
.regs
;
750 if (!cpu_has_feature(CPU_FTR_PPC_LE
) &&
751 !cpu_has_feature(CPU_FTR_REAL_LE
))
757 if (regs
->msr
& MSR_LE
) {
758 if (cpu_has_feature(CPU_FTR_REAL_LE
))
759 val
= PR_ENDIAN_LITTLE
;
761 val
= PR_ENDIAN_PPC_LITTLE
;
765 return put_user(val
, (unsigned int __user
*)adr
);
768 int set_unalign_ctl(struct task_struct
*tsk
, unsigned int val
)
770 tsk
->thread
.align_ctl
= val
;
774 int get_unalign_ctl(struct task_struct
*tsk
, unsigned long adr
)
776 return put_user(tsk
->thread
.align_ctl
, (unsigned int __user
*)adr
);
779 #define TRUNC_PTR(x) ((typeof(x))(((unsigned long)(x)) & 0xffffffff))
781 int sys_clone(unsigned long clone_flags
, unsigned long usp
,
782 int __user
*parent_tidp
, void __user
*child_threadptr
,
783 int __user
*child_tidp
, int p6
,
784 struct pt_regs
*regs
)
786 CHECK_FULL_REGS(regs
);
788 usp
= regs
->gpr
[1]; /* stack pointer for child */
790 if (test_thread_flag(TIF_32BIT
)) {
791 parent_tidp
= TRUNC_PTR(parent_tidp
);
792 child_tidp
= TRUNC_PTR(child_tidp
);
795 return do_fork(clone_flags
, usp
, regs
, 0, parent_tidp
, child_tidp
);
798 int sys_fork(unsigned long p1
, unsigned long p2
, unsigned long p3
,
799 unsigned long p4
, unsigned long p5
, unsigned long p6
,
800 struct pt_regs
*regs
)
802 CHECK_FULL_REGS(regs
);
803 return do_fork(SIGCHLD
, regs
->gpr
[1], regs
, 0, NULL
, NULL
);
806 int sys_vfork(unsigned long p1
, unsigned long p2
, unsigned long p3
,
807 unsigned long p4
, unsigned long p5
, unsigned long p6
,
808 struct pt_regs
*regs
)
810 CHECK_FULL_REGS(regs
);
811 return do_fork(CLONE_VFORK
| CLONE_VM
| SIGCHLD
, regs
->gpr
[1],
812 regs
, 0, NULL
, NULL
);
815 int sys_execve(unsigned long a0
, unsigned long a1
, unsigned long a2
,
816 unsigned long a3
, unsigned long a4
, unsigned long a5
,
817 struct pt_regs
*regs
)
822 filename
= getname((char __user
*) a0
);
823 error
= PTR_ERR(filename
);
824 if (IS_ERR(filename
))
826 flush_fp_to_thread(current
);
827 flush_altivec_to_thread(current
);
828 flush_spe_to_thread(current
);
829 error
= do_execve(filename
, (char __user
* __user
*) a1
,
830 (char __user
* __user
*) a2
, regs
);
833 current
->ptrace
&= ~PT_DTRACE
;
834 task_unlock(current
);
841 #ifdef CONFIG_IRQSTACKS
842 static inline int valid_irq_stack(unsigned long sp
, struct task_struct
*p
,
843 unsigned long nbytes
)
845 unsigned long stack_page
;
846 unsigned long cpu
= task_cpu(p
);
849 * Avoid crashing if the stack has overflowed and corrupted
850 * task_cpu(p), which is in the thread_info struct.
852 if (cpu
< NR_CPUS
&& cpu_possible(cpu
)) {
853 stack_page
= (unsigned long) hardirq_ctx
[cpu
];
854 if (sp
>= stack_page
+ sizeof(struct thread_struct
)
855 && sp
<= stack_page
+ THREAD_SIZE
- nbytes
)
858 stack_page
= (unsigned long) softirq_ctx
[cpu
];
859 if (sp
>= stack_page
+ sizeof(struct thread_struct
)
860 && sp
<= stack_page
+ THREAD_SIZE
- nbytes
)
867 #define valid_irq_stack(sp, p, nb) 0
868 #endif /* CONFIG_IRQSTACKS */
870 int validate_sp(unsigned long sp
, struct task_struct
*p
,
871 unsigned long nbytes
)
873 unsigned long stack_page
= (unsigned long)task_stack_page(p
);
875 if (sp
>= stack_page
+ sizeof(struct thread_struct
)
876 && sp
<= stack_page
+ THREAD_SIZE
- nbytes
)
879 return valid_irq_stack(sp
, p
, nbytes
);
883 #define MIN_STACK_FRAME 112 /* same as STACK_FRAME_OVERHEAD, in fact */
884 #define FRAME_LR_SAVE 2
885 #define INT_FRAME_SIZE (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD + 288)
886 #define REGS_MARKER 0x7265677368657265ul
887 #define FRAME_MARKER 12
889 #define MIN_STACK_FRAME 16
890 #define FRAME_LR_SAVE 1
891 #define INT_FRAME_SIZE (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD)
892 #define REGS_MARKER 0x72656773ul
893 #define FRAME_MARKER 2
896 EXPORT_SYMBOL(validate_sp
);
898 unsigned long get_wchan(struct task_struct
*p
)
900 unsigned long ip
, sp
;
903 if (!p
|| p
== current
|| p
->state
== TASK_RUNNING
)
907 if (!validate_sp(sp
, p
, MIN_STACK_FRAME
))
911 sp
= *(unsigned long *)sp
;
912 if (!validate_sp(sp
, p
, MIN_STACK_FRAME
))
915 ip
= ((unsigned long *)sp
)[FRAME_LR_SAVE
];
916 if (!in_sched_functions(ip
))
919 } while (count
++ < 16);
923 static int kstack_depth_to_print
= 64;
925 void show_stack(struct task_struct
*tsk
, unsigned long *stack
)
927 unsigned long sp
, ip
, lr
, newsp
;
931 sp
= (unsigned long) stack
;
936 asm("mr %0,1" : "=r" (sp
));
938 sp
= tsk
->thread
.ksp
;
942 printk("Call Trace:\n");
944 if (!validate_sp(sp
, tsk
, MIN_STACK_FRAME
))
947 stack
= (unsigned long *) sp
;
949 ip
= stack
[FRAME_LR_SAVE
];
950 if (!firstframe
|| ip
!= lr
) {
951 printk("["REG
"] ["REG
"] ", sp
, ip
);
952 print_symbol("%s", ip
);
954 printk(" (unreliable)");
960 * See if this is an exception frame.
961 * We look for the "regshere" marker in the current frame.
963 if (validate_sp(sp
, tsk
, INT_FRAME_SIZE
)
964 && stack
[FRAME_MARKER
] == REGS_MARKER
) {
965 struct pt_regs
*regs
= (struct pt_regs
*)
966 (sp
+ STACK_FRAME_OVERHEAD
);
967 printk("--- Exception: %lx", regs
->trap
);
968 print_symbol(" at %s\n", regs
->nip
);
970 print_symbol(" LR = %s\n", lr
);
975 } while (count
++ < kstack_depth_to_print
);
978 void dump_stack(void)
980 show_stack(current
, NULL
);
982 EXPORT_SYMBOL(dump_stack
);
985 void ppc64_runlatch_on(void)
989 if (cpu_has_feature(CPU_FTR_CTRL
) && !test_thread_flag(TIF_RUNLATCH
)) {
992 ctrl
= mfspr(SPRN_CTRLF
);
993 ctrl
|= CTRL_RUNLATCH
;
994 mtspr(SPRN_CTRLT
, ctrl
);
996 set_thread_flag(TIF_RUNLATCH
);
1000 void ppc64_runlatch_off(void)
1004 if (cpu_has_feature(CPU_FTR_CTRL
) && test_thread_flag(TIF_RUNLATCH
)) {
1007 clear_thread_flag(TIF_RUNLATCH
);
1009 ctrl
= mfspr(SPRN_CTRLF
);
1010 ctrl
&= ~CTRL_RUNLATCH
;
1011 mtspr(SPRN_CTRLT
, ctrl
);