2 * linux/arch/arm/kernel/process.c
4 * Copyright (C) 1996-2000 Russell King - Converted to ARM.
5 * Original Copyright (C) 1995 Linus Torvalds
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
13 #include <linux/export.h>
14 #include <linux/sched.h>
15 #include <linux/kernel.h>
17 #include <linux/stddef.h>
18 #include <linux/unistd.h>
19 #include <linux/user.h>
20 #include <linux/interrupt.h>
21 #include <linux/kallsyms.h>
22 #include <linux/init.h>
23 #include <linux/elfcore.h>
25 #include <linux/tick.h>
26 #include <linux/utsname.h>
27 #include <linux/uaccess.h>
28 #include <linux/random.h>
29 #include <linux/hw_breakpoint.h>
30 #include <linux/leds.h>
32 #include <asm/processor.h>
33 #include <asm/thread_notify.h>
34 #include <asm/stacktrace.h>
35 #include <asm/system_misc.h>
36 #include <asm/mach/time.h>
40 #ifdef CONFIG_CC_STACKPROTECTOR
41 #include <linux/stackprotector.h>
42 unsigned long __stack_chk_guard __read_mostly;
43 EXPORT_SYMBOL(__stack_chk_guard);
46 static const char *processor_modes[] __maybe_unused = {
47 "USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" , "UK4_26" , "UK5_26" , "UK6_26" , "UK7_26" ,
48 "UK8_26" , "UK9_26" , "UK10_26", "UK11_26", "UK12_26", "UK13_26", "UK14_26", "UK15_26",
49 "USER_32", "FIQ_32" , "IRQ_32" , "SVC_32" , "UK4_32" , "UK5_32" , "MON_32" , "ABT_32" ,
50 "UK8_32" , "UK9_32" , "HYP_32", "UND_32" , "UK12_32", "UK13_32", "UK14_32", "SYS_32"
53 static const char *isa_modes[] __maybe_unused = {
54 "ARM" , "Thumb" , "Jazelle", "ThumbEE"
58 * This is our default idle handler.
61 void (*arm_pm_idle)(void);
64 * Called from the core idle loop.
67 void arch_cpu_idle(void)
76 void arch_cpu_idle_prepare(void)
81 void arch_cpu_idle_enter(void)
83 idle_notifier_call_chain(IDLE_START);
84 ledtrig_cpu(CPU_LED_IDLE_START);
85 #ifdef CONFIG_PL310_ERRATA_769419
90 void arch_cpu_idle_exit(void)
92 ledtrig_cpu(CPU_LED_IDLE_END);
93 idle_notifier_call_chain(IDLE_END);
97 * dump a block of kernel memory from around the given address
99 static void show_data(unsigned long addr, int nbytes, const char *name)
106 * don't attempt to dump non-kernel addresses or
107 * values that are probably just small negative numbers
109 if (addr < PAGE_OFFSET || addr > -256UL)
112 printk("\n%s: %#lx:\n", name, addr);
115 * round address down to a 32 bit boundary
116 * and always dump a multiple of 32 bytes
118 p = (u32 *)(addr & ~(sizeof(u32) - 1));
119 nbytes += (addr & (sizeof(u32) - 1));
120 nlines = (nbytes + 31) / 32;
123 for (i = 0; i < nlines; i++) {
125 * just display low 16 bits of address to keep
126 * each line of the dump < 80 characters
128 printk("%04lx ", (unsigned long)p & 0xffff);
129 for (j = 0; j < 8; j++) {
131 if (probe_kernel_address(p, data)) {
134 printk(" %08x", data);
142 static void show_extra_register_data(struct pt_regs *regs, int nbytes)
148 show_data(regs->ARM_pc - nbytes, nbytes * 2, "PC");
149 show_data(regs->ARM_lr - nbytes, nbytes * 2, "LR");
150 show_data(regs->ARM_sp - nbytes, nbytes * 2, "SP");
151 show_data(regs->ARM_ip - nbytes, nbytes * 2, "IP");
152 show_data(regs->ARM_fp - nbytes, nbytes * 2, "FP");
153 show_data(regs->ARM_r0 - nbytes, nbytes * 2, "R0");
154 show_data(regs->ARM_r1 - nbytes, nbytes * 2, "R1");
155 show_data(regs->ARM_r2 - nbytes, nbytes * 2, "R2");
156 show_data(regs->ARM_r3 - nbytes, nbytes * 2, "R3");
157 show_data(regs->ARM_r4 - nbytes, nbytes * 2, "R4");
158 show_data(regs->ARM_r5 - nbytes, nbytes * 2, "R5");
159 show_data(regs->ARM_r6 - nbytes, nbytes * 2, "R6");
160 show_data(regs->ARM_r7 - nbytes, nbytes * 2, "R7");
161 show_data(regs->ARM_r8 - nbytes, nbytes * 2, "R8");
162 show_data(regs->ARM_r9 - nbytes, nbytes * 2, "R9");
163 show_data(regs->ARM_r10 - nbytes, nbytes * 2, "R10");
167 void __show_regs(struct pt_regs *regs)
171 #ifndef CONFIG_CPU_V7M
173 #ifdef CONFIG_CPU_SW_DOMAIN_PAN
175 * Get the domain register for the parent context. In user
176 * mode, we don't save the DACR, so lets use what it should
177 * be. For other modes, we place it after the pt_regs struct.
180 domain = DACR_UACCESS_ENABLE;
182 domain = *(unsigned int *)(regs + 1);
184 domain = get_domain();
188 show_regs_print_info(KERN_DEFAULT);
190 print_symbol("PC is at %s\n", instruction_pointer(regs));
191 print_symbol("LR is at %s\n", regs->ARM_lr);
192 printk("pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n"
193 "sp : %08lx ip : %08lx fp : %08lx\n",
194 regs->ARM_pc, regs->ARM_lr, regs->ARM_cpsr,
195 regs->ARM_sp, regs->ARM_ip, regs->ARM_fp);
196 printk("r10: %08lx r9 : %08lx r8 : %08lx\n",
197 regs->ARM_r10, regs->ARM_r9,
199 printk("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
200 regs->ARM_r7, regs->ARM_r6,
201 regs->ARM_r5, regs->ARM_r4);
202 printk("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
203 regs->ARM_r3, regs->ARM_r2,
204 regs->ARM_r1, regs->ARM_r0);
206 flags = regs->ARM_cpsr;
207 buf[0] = flags & PSR_N_BIT ? 'N' : 'n';
208 buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z';
209 buf[2] = flags & PSR_C_BIT ? 'C' : 'c';
210 buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
213 #ifndef CONFIG_CPU_V7M
217 if ((domain & domain_mask(DOMAIN_USER)) ==
218 domain_val(DOMAIN_USER, DOMAIN_NOACCESS))
220 else if (get_fs() == get_ds())
225 printk("Flags: %s IRQs o%s FIQs o%s Mode %s ISA %s Segment %s\n",
226 buf, interrupts_enabled(regs) ? "n" : "ff",
227 fast_interrupts_enabled(regs) ? "n" : "ff",
228 processor_modes[processor_mode(regs)],
229 isa_modes[isa_mode(regs)], segment);
232 printk("xPSR: %08lx\n", regs->ARM_cpsr);
235 #ifdef CONFIG_CPU_CP15
240 #ifdef CONFIG_CPU_CP15_MMU
242 unsigned int transbase;
243 asm("mrc p15, 0, %0, c2, c0\n\t"
245 snprintf(buf, sizeof(buf), " Table: %08x DAC: %08x",
249 asm("mrc p15, 0, %0, c1, c0\n" : "=r" (ctrl));
251 printk("Control: %08x%s\n", ctrl, buf);
255 show_extra_register_data(regs, 128);
258 void show_regs(struct pt_regs * regs)
264 ATOMIC_NOTIFIER_HEAD(thread_notify_head);
266 EXPORT_SYMBOL_GPL(thread_notify_head);
269 * Free current thread data structures etc..
271 void exit_thread(void)
273 thread_notify(THREAD_NOTIFY_EXIT, current_thread_info());
276 void flush_thread(void)
278 struct thread_info *thread = current_thread_info();
279 struct task_struct *tsk = current;
281 flush_ptrace_hw_breakpoint(tsk);
283 memset(thread->used_cp, 0, sizeof(thread->used_cp));
284 memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
285 memset(&thread->fpstate, 0, sizeof(union fp_state));
289 thread_notify(THREAD_NOTIFY_FLUSH, thread);
292 void release_thread(struct task_struct *dead_task)
296 asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
299 copy_thread(unsigned long clone_flags, unsigned long stack_start,
300 unsigned long stk_sz, struct task_struct *p)
302 struct thread_info *thread = task_thread_info(p);
303 struct pt_regs *childregs = task_pt_regs(p);
305 memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
307 #ifdef CONFIG_CPU_USE_DOMAINS
309 * Copy the initial value of the domain access control register
310 * from the current thread: thread->addr_limit will have been
311 * copied from the current thread via setup_thread_stack() in
314 thread->cpu_domain = get_domain();
317 if (likely(!(p->flags & PF_KTHREAD))) {
318 *childregs = *current_pt_regs();
319 childregs->ARM_r0 = 0;
321 childregs->ARM_sp = stack_start;
323 memset(childregs, 0, sizeof(struct pt_regs));
324 thread->cpu_context.r4 = stk_sz;
325 thread->cpu_context.r5 = stack_start;
326 childregs->ARM_cpsr = SVC_MODE;
328 thread->cpu_context.pc = (unsigned long)ret_from_fork;
329 thread->cpu_context.sp = (unsigned long)childregs;
331 clear_ptrace_hw_breakpoint(p);
333 if (clone_flags & CLONE_SETTLS)
334 thread->tp_value[0] = childregs->ARM_r3;
335 thread->tp_value[1] = get_tpuser();
337 thread_notify(THREAD_NOTIFY_COPY, thread);
343 * Fill in the task's elfregs structure for a core dump.
345 int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs)
347 elf_core_copy_regs(elfregs, task_pt_regs(t));
352 * fill in the fpe structure for a core dump...
354 int dump_fpu (struct pt_regs *regs, struct user_fp *fp)
356 struct thread_info *thread = current_thread_info();
357 int used_math = thread->used_cp[1] | thread->used_cp[2];
360 memcpy(fp, &thread->fpstate.soft, sizeof (*fp));
362 return used_math != 0;
364 EXPORT_SYMBOL(dump_fpu);
366 unsigned long get_wchan(struct task_struct *p)
368 struct stackframe frame;
369 unsigned long stack_page;
371 if (!p || p == current || p->state == TASK_RUNNING)
374 frame.fp = thread_saved_fp(p);
375 frame.sp = thread_saved_sp(p);
376 frame.lr = 0; /* recovered from the stack */
377 frame.pc = thread_saved_pc(p);
378 stack_page = (unsigned long)task_stack_page(p);
380 if (frame.sp < stack_page ||
381 frame.sp >= stack_page + THREAD_SIZE ||
382 unwind_frame(&frame) < 0)
384 if (!in_sched_functions(frame.pc))
386 } while (count ++ < 16);
390 unsigned long arch_randomize_brk(struct mm_struct *mm)
392 unsigned long range_end = mm->brk + 0x02000000;
393 return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
397 #ifdef CONFIG_KUSER_HELPERS
399 * The vectors page is always readable from user space for the
400 * atomic helpers. Insert it into the gate_vma so that it is visible
401 * through ptrace and /proc/<pid>/mem.
403 static struct vm_area_struct gate_vma = {
404 .vm_start = 0xffff0000,
405 .vm_end = 0xffff0000 + PAGE_SIZE,
406 .vm_flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYEXEC,
409 static int __init gate_vma_init(void)
411 gate_vma.vm_page_prot = PAGE_READONLY_EXEC;
414 arch_initcall(gate_vma_init);
416 struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
421 int in_gate_area(struct mm_struct *mm, unsigned long addr)
423 return (addr >= gate_vma.vm_start) && (addr < gate_vma.vm_end);
426 int in_gate_area_no_mm(unsigned long addr)
428 return in_gate_area(NULL, addr);
430 #define is_gate_vma(vma) ((vma) == &gate_vma)
432 #define is_gate_vma(vma) 0
435 const char *arch_vma_name(struct vm_area_struct *vma)
437 return is_gate_vma(vma) ? "[vectors]" : NULL;
440 /* If possible, provide a placement hint at a random offset from the
441 * stack for the sigpage and vdso pages.
443 static unsigned long sigpage_addr(const struct mm_struct *mm,
446 unsigned long offset;
452 first = PAGE_ALIGN(mm->start_stack);
454 last = TASK_SIZE - (npages << PAGE_SHIFT);
456 /* No room after stack? */
460 /* Just enough room? */
464 slots = ((last - first) >> PAGE_SHIFT) + 1;
466 offset = get_random_int() % slots;
468 addr = first + (offset << PAGE_SHIFT);
473 static struct page *signal_page;
474 extern struct page *get_signal_page(void);
476 static const struct vm_special_mapping sigpage_mapping = {
478 .pages = &signal_page,
481 int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
483 struct mm_struct *mm = current->mm;
484 struct vm_area_struct *vma;
485 unsigned long npages;
491 signal_page = get_signal_page();
495 npages = 1; /* for sigpage */
496 npages += vdso_total_pages;
498 down_write(&mm->mmap_sem);
499 hint = sigpage_addr(mm, npages);
500 addr = get_unmapped_area(NULL, hint, npages << PAGE_SHIFT, 0, 0);
501 if (IS_ERR_VALUE(addr)) {
506 vma = _install_special_mapping(mm, addr, PAGE_SIZE,
507 VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC,
515 mm->context.sigpage = addr;
517 /* Unlike the sigpage, failure to install the vdso is unlikely
518 * to be fatal to the process, so no error check needed
521 arm_install_vdso(mm, addr + PAGE_SIZE);
524 up_write(&mm->mmap_sem);