diff options
Diffstat (limited to 'libdde_linux26/contrib/arch/arm/kernel/traps.c')
| -rw-r--r-- | libdde_linux26/contrib/arch/arm/kernel/traps.c | 734 |
1 files changed, 0 insertions, 734 deletions
diff --git a/libdde_linux26/contrib/arch/arm/kernel/traps.c b/libdde_linux26/contrib/arch/arm/kernel/traps.c deleted file mode 100644 index 79abc4dd..00000000 --- a/libdde_linux26/contrib/arch/arm/kernel/traps.c +++ /dev/null @@ -1,734 +0,0 @@ -/* - * linux/arch/arm/kernel/traps.c - * - * Copyright (C) 1995-2002 Russell King - * Fragments that appear the same as linux/arch/i386/kernel/traps.c (C) Linus Torvalds - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - * - * 'traps.c' handles hardware exceptions after we have saved some state in - * 'linux/arch/arm/lib/traps.S'. Mostly a debugging aid, but will probably - * kill the offending process. - */ -#include <linux/module.h> -#include <linux/signal.h> -#include <linux/spinlock.h> -#include <linux/personality.h> -#include <linux/kallsyms.h> -#include <linux/delay.h> -#include <linux/hardirq.h> -#include <linux/init.h> -#include <linux/uaccess.h> - -#include <asm/atomic.h> -#include <asm/cacheflush.h> -#include <asm/system.h> -#include <asm/unistd.h> -#include <asm/traps.h> - -#include "ptrace.h" -#include "signal.h" - -static const char *handler[]= { "prefetch abort", "data abort", "address exception", "interrupt" }; - -#ifdef CONFIG_DEBUG_USER -unsigned int user_debug; - -static int __init user_debug_setup(char *str) -{ - get_option(&str, &user_debug); - return 1; -} -__setup("user_debug=", user_debug_setup); -#endif - -static void dump_mem(const char *str, unsigned long bottom, unsigned long top); - -void dump_backtrace_entry(unsigned long where, unsigned long from, unsigned long frame) -{ -#ifdef CONFIG_KALLSYMS - printk("[<%08lx>] ", where); - print_symbol("(%s) ", where); - printk("from [<%08lx>] ", from); - print_symbol("(%s)\n", from); -#else - printk("Function entered at [<%08lx>] from [<%08lx>]\n", where, from); -#endif - - if (in_exception_text(where)) - dump_mem("Exception stack", frame + 4, frame + 4 + sizeof(struct pt_regs)); -} - -/* - * Stack pointers should always be within the kernels view of - * physical memory. If it is not there, then we can't dump - * out any information relating to the stack. - */ -static int verify_stack(unsigned long sp) -{ - if (sp < PAGE_OFFSET || - (sp > (unsigned long)high_memory && high_memory != NULL)) - return -EFAULT; - - return 0; -} - -/* - * Dump out the contents of some memory nicely... - */ -static void dump_mem(const char *str, unsigned long bottom, unsigned long top) -{ - unsigned long p = bottom & ~31; - mm_segment_t fs; - int i; - - /* - * We need to switch to kernel mode so that we can use __get_user - * to safely read from kernel space. Note that we now dump the - * code first, just in case the backtrace kills us. - */ - fs = get_fs(); - set_fs(KERNEL_DS); - - printk("%s(0x%08lx to 0x%08lx)\n", str, bottom, top); - - for (p = bottom & ~31; p < top;) { - printk("%04lx: ", p & 0xffff); - - for (i = 0; i < 8; i++, p += 4) { - unsigned int val; - - if (p < bottom || p >= top) - printk(" "); - else { - __get_user(val, (unsigned long *)p); - printk("%08x ", val); - } - } - printk ("\n"); - } - - set_fs(fs); -} - -static void dump_instr(struct pt_regs *regs) -{ - unsigned long addr = instruction_pointer(regs); - const int thumb = thumb_mode(regs); - const int width = thumb ? 4 : 8; - mm_segment_t fs; - int i; - - /* - * We need to switch to kernel mode so that we can use __get_user - * to safely read from kernel space. Note that we now dump the - * code first, just in case the backtrace kills us. - */ - fs = get_fs(); - set_fs(KERNEL_DS); - - printk("Code: "); - for (i = -4; i < 1; i++) { - unsigned int val, bad; - - if (thumb) - bad = __get_user(val, &((u16 *)addr)[i]); - else - bad = __get_user(val, &((u32 *)addr)[i]); - - if (!bad) - printk(i == 0 ? "(%0*x) " : "%0*x ", width, val); - else { - printk("bad PC value."); - break; - } - } - printk("\n"); - - set_fs(fs); -} - -static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk) -{ - unsigned int fp; - int ok = 1; - - printk("Backtrace: "); - fp = regs->ARM_fp; - if (!fp) { - printk("no frame pointer"); - ok = 0; - } else if (verify_stack(fp)) { - printk("invalid frame pointer 0x%08x", fp); - ok = 0; - } else if (fp < (unsigned long)end_of_stack(tsk)) - printk("frame pointer underflow"); - printk("\n"); - - if (ok) - c_backtrace(fp, processor_mode(regs)); -} - -void dump_stack(void) -{ - __backtrace(); -} - -EXPORT_SYMBOL(dump_stack); - -void show_stack(struct task_struct *tsk, unsigned long *sp) -{ - unsigned long fp; - - if (!tsk) - tsk = current; - - if (tsk != current) - fp = thread_saved_fp(tsk); - else - asm("mov %0, fp" : "=r" (fp) : : "cc"); - - c_backtrace(fp, 0x10); - barrier(); -} - -#ifdef CONFIG_PREEMPT -#define S_PREEMPT " PREEMPT" -#else -#define S_PREEMPT "" -#endif -#ifdef CONFIG_SMP -#define S_SMP " SMP" -#else -#define S_SMP "" -#endif - -static void __die(const char *str, int err, struct thread_info *thread, struct pt_regs *regs) -{ - struct task_struct *tsk = thread->task; - static int die_counter; - - printk("Internal error: %s: %x [#%d]" S_PREEMPT S_SMP "\n", - str, err, ++die_counter); - print_modules(); - __show_regs(regs); - printk("Process %s (pid: %d, stack limit = 0x%p)\n", - tsk->comm, task_pid_nr(tsk), thread + 1); - - if (!user_mode(regs) || in_interrupt()) { - dump_mem("Stack: ", regs->ARM_sp, - THREAD_SIZE + (unsigned long)task_stack_page(tsk)); - dump_backtrace(regs, tsk); - dump_instr(regs); - } -} - -DEFINE_SPINLOCK(die_lock); - -/* - * This function is protected against re-entrancy. - */ -NORET_TYPE void die(const char *str, struct pt_regs *regs, int err) -{ - struct thread_info *thread = current_thread_info(); - - oops_enter(); - - console_verbose(); - spin_lock_irq(&die_lock); - bust_spinlocks(1); - __die(str, err, thread, regs); - bust_spinlocks(0); - add_taint(TAINT_DIE); - spin_unlock_irq(&die_lock); - - if (in_interrupt()) - panic("Fatal exception in interrupt"); - - if (panic_on_oops) - panic("Fatal exception"); - - oops_exit(); - do_exit(SIGSEGV); -} - -void arm_notify_die(const char *str, struct pt_regs *regs, - struct siginfo *info, unsigned long err, unsigned long trap) -{ - if (user_mode(regs)) { - current->thread.error_code = err; - current->thread.trap_no = trap; - - force_sig_info(info->si_signo, info, current); - } else { - die(str, regs, err); - } -} - -static LIST_HEAD(undef_hook); -static DEFINE_SPINLOCK(undef_lock); - -void register_undef_hook(struct undef_hook *hook) -{ - unsigned long flags; - - spin_lock_irqsave(&undef_lock, flags); - list_add(&hook->node, &undef_hook); - spin_unlock_irqrestore(&undef_lock, flags); -} - -void unregister_undef_hook(struct undef_hook *hook) -{ - unsigned long flags; - - spin_lock_irqsave(&undef_lock, flags); - list_del(&hook->node); - spin_unlock_irqrestore(&undef_lock, flags); -} - -static int call_undef_hook(struct pt_regs *regs, unsigned int instr) -{ - struct undef_hook *hook; - unsigned long flags; - int (*fn)(struct pt_regs *regs, unsigned int instr) = NULL; - - spin_lock_irqsave(&undef_lock, flags); - list_for_each_entry(hook, &undef_hook, node) - if ((instr & hook->instr_mask) == hook->instr_val && - (regs->ARM_cpsr & hook->cpsr_mask) == hook->cpsr_val) - fn = hook->fn; - spin_unlock_irqrestore(&undef_lock, flags); - - return fn ? fn(regs, instr) : 1; -} - -asmlinkage void __exception do_undefinstr(struct pt_regs *regs) -{ - unsigned int correction = thumb_mode(regs) ? 2 : 4; - unsigned int instr; - siginfo_t info; - void __user *pc; - - /* - * According to the ARM ARM, PC is 2 or 4 bytes ahead, - * depending whether we're in Thumb mode or not. - * Correct this offset. - */ - regs->ARM_pc -= correction; - - pc = (void __user *)instruction_pointer(regs); - - if (processor_mode(regs) == SVC_MODE) { - instr = *(u32 *) pc; - } else if (thumb_mode(regs)) { - get_user(instr, (u16 __user *)pc); - } else { - get_user(instr, (u32 __user *)pc); - } - - if (call_undef_hook(regs, instr) == 0) - return; - -#ifdef CONFIG_DEBUG_USER - if (user_debug & UDBG_UNDEFINED) { - printk(KERN_INFO "%s (%d): undefined instruction: pc=%p\n", - current->comm, task_pid_nr(current), pc); - dump_instr(regs); - } -#endif - - info.si_signo = SIGILL; - info.si_errno = 0; - info.si_code = ILL_ILLOPC; - info.si_addr = pc; - - arm_notify_die("Oops - undefined instruction", regs, &info, 0, 6); -} - -asmlinkage void do_unexp_fiq (struct pt_regs *regs) -{ - printk("Hmm. Unexpected FIQ received, but trying to continue\n"); - printk("You may have a hardware problem...\n"); -} - -/* - * bad_mode handles the impossible case in the vectors. If you see one of - * these, then it's extremely serious, and could mean you have buggy hardware. - * It never returns, and never tries to sync. We hope that we can at least - * dump out some state information... - */ -asmlinkage void bad_mode(struct pt_regs *regs, int reason) -{ - console_verbose(); - - printk(KERN_CRIT "Bad mode in %s handler detected\n", handler[reason]); - - die("Oops - bad mode", regs, 0); - local_irq_disable(); - panic("bad mode"); -} - -static int bad_syscall(int n, struct pt_regs *regs) -{ - struct thread_info *thread = current_thread_info(); - siginfo_t info; - - if (current->personality != PER_LINUX && - current->personality != PER_LINUX_32BIT && - thread->exec_domain->handler) { - thread->exec_domain->handler(n, regs); - return regs->ARM_r0; - } - -#ifdef CONFIG_DEBUG_USER - if (user_debug & UDBG_SYSCALL) { - printk(KERN_ERR "[%d] %s: obsolete system call %08x.\n", - task_pid_nr(current), current->comm, n); - dump_instr(regs); - } -#endif - - info.si_signo = SIGILL; - info.si_errno = 0; - info.si_code = ILL_ILLTRP; - info.si_addr = (void __user *)instruction_pointer(regs) - - (thumb_mode(regs) ? 2 : 4); - - arm_notify_die("Oops - bad syscall", regs, &info, n, 0); - - return regs->ARM_r0; -} - -static inline void -do_cache_op(unsigned long start, unsigned long end, int flags) -{ - struct vm_area_struct *vma; - - if (end < start || flags) - return; - - vma = find_vma(current->active_mm, start); - if (vma && vma->vm_start < end) { - if (start < vma->vm_start) - start = vma->vm_start; - if (end > vma->vm_end) - end = vma->vm_end; - - flush_cache_user_range(vma, start, end); - } -} - -/* - * Handle all unrecognised system calls. - * 0x9f0000 - 0x9fffff are some more esoteric system calls - */ -#define NR(x) ((__ARM_NR_##x) - __ARM_NR_BASE) -asmlinkage int arm_syscall(int no, struct pt_regs *regs) -{ - struct thread_info *thread = current_thread_info(); - siginfo_t info; - - if ((no >> 16) != (__ARM_NR_BASE>> 16)) - return bad_syscall(no, regs); - - switch (no & 0xffff) { - case 0: /* branch through 0 */ - info.si_signo = SIGSEGV; - info.si_errno = 0; - info.si_code = SEGV_MAPERR; - info.si_addr = NULL; - - arm_notify_die("branch through zero", regs, &info, 0, 0); - return 0; - - case NR(breakpoint): /* SWI BREAK_POINT */ - regs->ARM_pc -= thumb_mode(regs) ? 2 : 4; - ptrace_break(current, regs); - return regs->ARM_r0; - - /* - * Flush a region from virtual address 'r0' to virtual address 'r1' - * _exclusive_. There is no alignment requirement on either address; - * user space does not need to know the hardware cache layout. - * - * r2 contains flags. It should ALWAYS be passed as ZERO until it - * is defined to be something else. For now we ignore it, but may - * the fires of hell burn in your belly if you break this rule. ;) - * - * (at a later date, we may want to allow this call to not flush - * various aspects of the cache. Passing '0' will guarantee that - * everything necessary gets flushed to maintain consistency in - * the specified region). - */ - case NR(cacheflush): - do_cache_op(regs->ARM_r0, regs->ARM_r1, regs->ARM_r2); - return 0; - - case NR(usr26): - if (!(elf_hwcap & HWCAP_26BIT)) - break; - regs->ARM_cpsr &= ~MODE32_BIT; - return regs->ARM_r0; - - case NR(usr32): - if (!(elf_hwcap & HWCAP_26BIT)) - break; - regs->ARM_cpsr |= MODE32_BIT; - return regs->ARM_r0; - - case NR(set_tls): - thread->tp_value = regs->ARM_r0; -#if defined(CONFIG_HAS_TLS_REG) - asm ("mcr p15, 0, %0, c13, c0, 3" : : "r" (regs->ARM_r0) ); -#elif !defined(CONFIG_TLS_REG_EMUL) - /* - * User space must never try to access this directly. - * Expect your app to break eventually if you do so. - * The user helper at 0xffff0fe0 must be used instead. - * (see entry-armv.S for details) - */ - *((unsigned int *)0xffff0ff0) = regs->ARM_r0; -#endif - return 0; - -#ifdef CONFIG_NEEDS_SYSCALL_FOR_CMPXCHG - /* - * Atomically store r1 in *r2 if *r2 is equal to r0 for user space. - * Return zero in r0 if *MEM was changed or non-zero if no exchange - * happened. Also set the user C flag accordingly. - * If access permissions have to be fixed up then non-zero is - * returned and the operation has to be re-attempted. - * - * *NOTE*: This is a ghost syscall private to the kernel. Only the - * __kuser_cmpxchg code in entry-armv.S should be aware of its - * existence. Don't ever use this from user code. - */ - case 0xfff0: - for (;;) { - extern void do_DataAbort(unsigned long addr, unsigned int fsr, - struct pt_regs *regs); - unsigned long val; - unsigned long addr = regs->ARM_r2; - struct mm_struct *mm = current->mm; - pgd_t *pgd; pmd_t *pmd; pte_t *pte; - spinlock_t *ptl; - - regs->ARM_cpsr &= ~PSR_C_BIT; - down_read(&mm->mmap_sem); - pgd = pgd_offset(mm, addr); - if (!pgd_present(*pgd)) - goto bad_access; - pmd = pmd_offset(pgd, addr); - if (!pmd_present(*pmd)) - goto bad_access; - pte = pte_offset_map_lock(mm, pmd, addr, &ptl); - if (!pte_present(*pte) || !pte_dirty(*pte)) { - pte_unmap_unlock(pte, ptl); - goto bad_access; - } - val = *(unsigned long *)addr; - val -= regs->ARM_r0; - if (val == 0) { - *(unsigned long *)addr = regs->ARM_r1; - regs->ARM_cpsr |= PSR_C_BIT; - } - pte_unmap_unlock(pte, ptl); - up_read(&mm->mmap_sem); - return val; - - bad_access: - up_read(&mm->mmap_sem); - /* simulate a write access fault */ - do_DataAbort(addr, 15 + (1 << 11), regs); - } -#endif - - default: - /* Calls 9f00xx..9f07ff are defined to return -ENOSYS - if not implemented, rather than raising SIGILL. This - way the calling program can gracefully determine whether - a feature is supported. */ - if (no <= 0x7ff) - return -ENOSYS; - break; - } -#ifdef CONFIG_DEBUG_USER - /* - * experience shows that these seem to indicate that - * something catastrophic has happened - */ - if (user_debug & UDBG_SYSCALL) { - printk("[%d] %s: arm syscall %d\n", - task_pid_nr(current), current->comm, no); - dump_instr(regs); - if (user_mode(regs)) { - __show_regs(regs); - c_backtrace(regs->ARM_fp, processor_mode(regs)); - } - } -#endif - info.si_signo = SIGILL; - info.si_errno = 0; - info.si_code = ILL_ILLTRP; - info.si_addr = (void __user *)instruction_pointer(regs) - - (thumb_mode(regs) ? 2 : 4); - - arm_notify_die("Oops - bad syscall(2)", regs, &info, no, 0); - return 0; -} - -#ifdef CONFIG_TLS_REG_EMUL - -/* - * We might be running on an ARMv6+ processor which should have the TLS - * register but for some reason we can't use it, or maybe an SMP system - * using a pre-ARMv6 processor (there are apparently a few prototypes like - * that in existence) and therefore access to that register must be - * emulated. - */ - -static int get_tp_trap(struct pt_regs *regs, unsigned int instr) -{ - int reg = (instr >> 12) & 15; - if (reg == 15) - return 1; - regs->uregs[reg] = current_thread_info()->tp_value; - regs->ARM_pc += 4; - return 0; -} - -static struct undef_hook arm_mrc_hook = { - .instr_mask = 0x0fff0fff, - .instr_val = 0x0e1d0f70, - .cpsr_mask = PSR_T_BIT, - .cpsr_val = 0, - .fn = get_tp_trap, -}; - -static int __init arm_mrc_hook_init(void) -{ - register_undef_hook(&arm_mrc_hook); - return 0; -} - -late_initcall(arm_mrc_hook_init); - -#endif - -void __bad_xchg(volatile void *ptr, int size) -{ - printk("xchg: bad data size: pc 0x%p, ptr 0x%p, size %d\n", - __builtin_return_address(0), ptr, size); - BUG(); -} -EXPORT_SYMBOL(__bad_xchg); - -/* - * A data abort trap was taken, but we did not handle the instruction. - * Try to abort the user program, or panic if it was the kernel. - */ -asmlinkage void -baddataabort(int code, unsigned long instr, struct pt_regs *regs) -{ - unsigned long addr = instruction_pointer(regs); - siginfo_t info; - -#ifdef CONFIG_DEBUG_USER - if (user_debug & UDBG_BADABORT) { - printk(KERN_ERR "[%d] %s: bad data abort: code %d instr 0x%08lx\n", - task_pid_nr(current), current->comm, code, instr); - dump_instr(regs); - show_pte(current->mm, addr); - } -#endif - - info.si_signo = SIGILL; - info.si_errno = 0; - info.si_code = ILL_ILLOPC; - info.si_addr = (void __user *)addr; - - arm_notify_die("unknown data abort code", regs, &info, instr, 0); -} - -void __attribute__((noreturn)) __bug(const char *file, int line) -{ - printk(KERN_CRIT"kernel BUG at %s:%d!\n", file, line); - *(int *)0 = 0; - - /* Avoid "noreturn function does return" */ - for (;;); -} -EXPORT_SYMBOL(__bug); - -void __readwrite_bug(const char *fn) -{ - printk("%s called, but not implemented\n", fn); - BUG(); -} -EXPORT_SYMBOL(__readwrite_bug); - -void __pte_error(const char *file, int line, unsigned long val) -{ - printk("%s:%d: bad pte %08lx.\n", file, line, val); -} - -void __pmd_error(const char *file, int line, unsigned long val) -{ - printk("%s:%d: bad pmd %08lx.\n", file, line, val); -} - -void __pgd_error(const char *file, int line, unsigned long val) -{ - printk("%s:%d: bad pgd %08lx.\n", file, line, val); -} - -asmlinkage void __div0(void) -{ - printk("Division by zero in kernel.\n"); - dump_stack(); -} -EXPORT_SYMBOL(__div0); - -void abort(void) -{ - BUG(); - - /* if that doesn't kill us, halt */ - panic("Oops failed to kill thread"); -} -EXPORT_SYMBOL(abort); - -void __init trap_init(void) -{ - return; -} - -void __init early_trap_init(void) -{ - unsigned long vectors = CONFIG_VECTORS_BASE; - extern char __stubs_start[], __stubs_end[]; - extern char __vectors_start[], __vectors_end[]; - extern char __kuser_helper_start[], __kuser_helper_end[]; - int kuser_sz = __kuser_helper_end - __kuser_helper_start; - - /* - * Copy the vectors, stubs and kuser helpers (in entry-armv.S) - * into the vector page, mapped at 0xffff0000, and ensure these - * are visible to the instruction stream. - */ - memcpy((void *)vectors, __vectors_start, __vectors_end - __vectors_start); - memcpy((void *)vectors + 0x200, __stubs_start, __stubs_end - __stubs_start); - memcpy((void *)vectors + 0x1000 - kuser_sz, __kuser_helper_start, kuser_sz); - - /* - * Copy signal return handlers into the vector page, and - * set sigreturn to be a pointer to these. - */ - memcpy((void *)KERN_SIGRETURN_CODE, sigreturn_codes, - sizeof(sigreturn_codes)); - - flush_icache_range(vectors, vectors + PAGE_SIZE); - modify_domain(DOMAIN_USER, DOMAIN_CLIENT); -} |