diff options
Diffstat (limited to 'arch/arm/kernel/traps.c')
| -rw-r--r-- | arch/arm/kernel/traps.c | 542 |
1 files changed, 359 insertions, 183 deletions
diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c index 5595fdd75e8..abd2fc06773 100644 --- a/arch/arm/kernel/traps.c +++ b/arch/arm/kernel/traps.c @@ -1,7 +1,7 @@ /* * linux/arch/arm/kernel/traps.c * - * Copyright (C) 1995-2002 Russell King + * Copyright (C) 1995-2009 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 @@ -12,27 +12,39 @@ * '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/spinlock.h> +#include <linux/uaccess.h> +#include <linux/hardirq.h> +#include <linux/kdebug.h> +#include <linux/module.h> +#include <linux/kexec.h> +#include <linux/bug.h> #include <linux/delay.h> #include <linux/init.h> -#include <linux/kprobes.h> +#include <linux/sched.h> -#include <asm/atomic.h> +#include <linux/atomic.h> #include <asm/cacheflush.h> -#include <asm/system.h> -#include <asm/uaccess.h> +#include <asm/exception.h> #include <asm/unistd.h> #include <asm/traps.h> -#include <asm/io.h> - -#include "ptrace.h" -#include "signal.h" +#include <asm/unwind.h> +#include <asm/tls.h> +#include <asm/system_misc.h> +#include <asm/opcodes.h> + +static const char *handler[]= { + "prefetch abort", + "data abort", + "address exception", + "interrupt", + "undefined instruction", +}; -static const char *handler[]= { "prefetch abort", "data abort", "address exception", "interrupt" }; +void *vectors_page; #ifdef CONFIG_DEBUG_USER unsigned int user_debug; @@ -45,23 +57,21 @@ static int __init user_debug_setup(char *str) __setup("user_debug=", user_debug_setup); #endif -static void dump_mem(const char *str, unsigned long bottom, unsigned long top); +static void dump_mem(const char *, const char *, unsigned long, unsigned long); 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); + printk("[<%08lx>] (%ps) from [<%08lx>] (%pS)\n", where, (void *)where, from, (void *)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)); + dump_mem("", "Exception stack", frame + 4, frame + 4 + sizeof(struct pt_regs)); } +#ifndef CONFIG_ARM_UNWIND /* * Stack pointers should always be within the kernels view of * physical memory. If it is not there, then we can't dump @@ -69,18 +79,21 @@ void dump_backtrace_entry(unsigned long where, unsigned long from, unsigned long */ static int verify_stack(unsigned long sp) { - if (sp < PAGE_OFFSET || (sp > (unsigned long)high_memory && high_memory != 0)) + if (sp < PAGE_OFFSET || + (sp > (unsigned long)high_memory && high_memory != NULL)) return -EFAULT; return 0; } +#endif /* * Dump out the contents of some memory nicely... */ -static void dump_mem(const char *str, unsigned long bottom, unsigned long top) +static void dump_mem(const char *lvl, const char *str, unsigned long bottom, + unsigned long top) { - unsigned long p = bottom & ~31; + unsigned long first; mm_segment_t fs; int i; @@ -92,33 +105,37 @@ static void dump_mem(const char *str, unsigned long bottom, unsigned long top) fs = get_fs(); set_fs(KERNEL_DS); - printk("%s(0x%08lx to 0x%08lx)\n", str, bottom, top); + printk("%s%s(0x%08lx to 0x%08lx)\n", lvl, str, bottom, top); - for (p = bottom & ~31; p < top;) { - printk("%04lx: ", p & 0xffff); + for (first = bottom & ~31; first < top; first += 32) { + unsigned long p; + char str[sizeof(" 12345678") * 8 + 1]; - for (i = 0; i < 8; i++, p += 4) { - unsigned int val; + memset(str, ' ', sizeof(str)); + str[sizeof(str) - 1] = '\0'; - if (p < bottom || p >= top) - printk(" "); - else { - __get_user(val, (unsigned long *)p); - printk("%08x ", val); + for (p = first, i = 0; i < 8 && p < top; i++, p += 4) { + if (p >= bottom && p < top) { + unsigned long val; + if (__get_user(val, (unsigned long *)p) == 0) + sprintf(str + i * 9, " %08lx", val); + else + sprintf(str + i * 9, " ????????"); } } - printk ("\n"); + printk("%s%04lx:%s\n", lvl, first & 0xffff, str); } set_fs(fs); } -static void dump_instr(struct pt_regs *regs) +static void dump_instr(const char *lvl, 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; + char str[sizeof("00000000 ") * 5 + 2 + 1], *p = str; int i; /* @@ -129,8 +146,7 @@ static void dump_instr(struct pt_regs *regs) fs = get_fs(); set_fs(KERNEL_DS); - printk("Code: "); - for (i = -4; i < 1; i++) { + for (i = -4; i < 1 + !!thumb; i++) { unsigned int val, bad; if (thumb) @@ -139,24 +155,45 @@ static void dump_instr(struct pt_regs *regs) bad = __get_user(val, &((u32 *)addr)[i]); if (!bad) - printk(i == 0 ? "(%0*x) " : "%0*x ", width, val); + p += sprintf(p, i == 0 ? "(%0*x) " : "%0*x ", + width, val); else { - printk("bad PC value."); + p += sprintf(p, "bad PC value"); break; } } - printk("\n"); + printk("%sCode: %s\n", lvl, str); set_fs(fs); } +#ifdef CONFIG_ARM_UNWIND +static inline void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk) +{ + unwind_backtrace(regs, tsk); +} +#else static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk) { - unsigned int fp; + unsigned int fp, mode; int ok = 1; printk("Backtrace: "); - fp = regs->ARM_fp; + + if (!tsk) + tsk = current; + + if (regs) { + fp = regs->ARM_fp; + mode = processor_mode(regs); + } else if (tsk != current) { + fp = thread_saved_fp(tsk); + mode = 0x10; + } else { + asm("mov %0, fp" : "=r" (fp) : : "cc"); + mode = 0x10; + } + if (!fp) { printk("no frame pointer"); ok = 0; @@ -168,29 +205,13 @@ static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk) printk("\n"); if (ok) - c_backtrace(fp, processor_mode(regs)); + c_backtrace(fp, mode); } - -void dump_stack(void) -{ - __backtrace(); -} - -EXPORT_SYMBOL(dump_stack); +#endif 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); + dump_backtrace(NULL, tsk); barrier(); } @@ -204,54 +225,109 @@ void show_stack(struct task_struct *tsk, unsigned long *sp) #else #define S_SMP "" #endif +#ifdef CONFIG_THUMB2_KERNEL +#define S_ISA " THUMB2" +#else +#define S_ISA " ARM" +#endif -static void __die(const char *str, int err, struct thread_info *thread, struct pt_regs *regs) +static int __die(const char *str, int err, struct pt_regs *regs) { - struct task_struct *tsk = thread->task; + struct task_struct *tsk = current; static int die_counter; + int ret; + + printk(KERN_EMERG "Internal error: %s: %x [#%d]" S_PREEMPT S_SMP + S_ISA "\n", str, err, ++die_counter); + + /* trap and error numbers are mostly meaningless on ARM */ + ret = notify_die(DIE_OOPS, str, regs, err, tsk->thread.trap_no, SIGSEGV); + if (ret == NOTIFY_STOP) + return 1; - 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); + printk(KERN_EMERG "Process %.*s (pid: %d, stack limit = 0x%p)\n", + TASK_COMM_LEN, tsk->comm, task_pid_nr(tsk), end_of_stack(tsk)); if (!user_mode(regs) || in_interrupt()) { - dump_mem("Stack: ", regs->ARM_sp, + dump_mem(KERN_EMERG, "Stack: ", regs->ARM_sp, THREAD_SIZE + (unsigned long)task_stack_page(tsk)); dump_backtrace(regs, tsk); - dump_instr(regs); + dump_instr(KERN_EMERG, regs); } + + return 0; } -DEFINE_SPINLOCK(die_lock); +static arch_spinlock_t die_lock = __ARCH_SPIN_LOCK_UNLOCKED; +static int die_owner = -1; +static unsigned int die_nest_count; -/* - * This function is protected against re-entrancy. - */ -NORET_TYPE void die(const char *str, struct pt_regs *regs, int err) +static unsigned long oops_begin(void) { - struct thread_info *thread = current_thread_info(); + int cpu; + unsigned long flags; oops_enter(); + /* racy, but better than risking deadlock. */ + raw_local_irq_save(flags); + cpu = smp_processor_id(); + if (!arch_spin_trylock(&die_lock)) { + if (cpu == die_owner) + /* nested oops. should stop eventually */; + else + arch_spin_lock(&die_lock); + } + die_nest_count++; + die_owner = cpu; console_verbose(); - spin_lock_irq(&die_lock); bust_spinlocks(1); - __die(str, err, thread, regs); + return flags; +} + +static void oops_end(unsigned long flags, struct pt_regs *regs, int signr) +{ + if (regs && kexec_should_crash(current)) + crash_kexec(regs); + bust_spinlocks(0); - add_taint(TAINT_DIE); - spin_unlock_irq(&die_lock); + die_owner = -1; + add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE); + die_nest_count--; + if (!die_nest_count) + /* Nest count reaches zero, release the lock. */ + arch_spin_unlock(&die_lock); + raw_local_irq_restore(flags); + oops_exit(); if (in_interrupt()) panic("Fatal exception in interrupt"); - if (panic_on_oops) panic("Fatal exception"); + if (signr) + do_exit(signr); +} - oops_exit(); - do_exit(SIGSEGV); +/* + * This function is protected against re-entrancy. + */ +void die(const char *str, struct pt_regs *regs, int err) +{ + enum bug_trap_type bug_type = BUG_TRAP_TYPE_NONE; + unsigned long flags = oops_begin(); + int sig = SIGSEGV; + + if (!user_mode(regs)) + bug_type = report_bug(regs->ARM_pc, regs); + if (bug_type != BUG_TRAP_TYPE_NONE) + str = "Oops - BUG"; + + if (__die(str, err, regs)) + sig = 0; + + oops_end(flags, regs, sig); } void arm_notify_die(const char *str, struct pt_regs *regs, @@ -267,81 +343,110 @@ void arm_notify_die(const char *str, struct pt_regs *regs, } } +#ifdef CONFIG_GENERIC_BUG + +int is_valid_bugaddr(unsigned long pc) +{ +#ifdef CONFIG_THUMB2_KERNEL + u16 bkpt; + u16 insn = __opcode_to_mem_thumb16(BUG_INSTR_VALUE); +#else + u32 bkpt; + u32 insn = __opcode_to_mem_arm(BUG_INSTR_VALUE); +#endif + + if (probe_kernel_address((unsigned *)pc, bkpt)) + return 0; + + return bkpt == insn; +} + +#endif + static LIST_HEAD(undef_hook); -static DEFINE_SPINLOCK(undef_lock); +static DEFINE_RAW_SPINLOCK(undef_lock); void register_undef_hook(struct undef_hook *hook) { unsigned long flags; - spin_lock_irqsave(&undef_lock, flags); + raw_spin_lock_irqsave(&undef_lock, flags); list_add(&hook->node, &undef_hook); - spin_unlock_irqrestore(&undef_lock, flags); + raw_spin_unlock_irqrestore(&undef_lock, flags); } void unregister_undef_hook(struct undef_hook *hook) { unsigned long flags; - spin_lock_irqsave(&undef_lock, flags); + raw_spin_lock_irqsave(&undef_lock, flags); list_del(&hook->node); - spin_unlock_irqrestore(&undef_lock, flags); + raw_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; + + raw_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; + raw_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; - struct undef_hook *hook; siginfo_t info; void __user *pc; - unsigned long flags; - - /* - * 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; +#ifdef CONFIG_THUMB2_KERNEL + if (thumb_mode(regs)) { + instr = __mem_to_opcode_thumb16(((u16 *)pc)[0]); + if (is_wide_instruction(instr)) { + u16 inst2; + inst2 = __mem_to_opcode_thumb16(((u16 *)pc)[1]); + instr = __opcode_thumb32_compose(instr, inst2); + } + } else +#endif + instr = __mem_to_opcode_arm(*(u32 *) pc); } else if (thumb_mode(regs)) { - get_user(instr, (u16 __user *)pc); + if (get_user(instr, (u16 __user *)pc)) + goto die_sig; + instr = __mem_to_opcode_thumb16(instr); + if (is_wide_instruction(instr)) { + unsigned int instr2; + if (get_user(instr2, (u16 __user *)pc+1)) + goto die_sig; + instr2 = __mem_to_opcode_thumb16(instr2); + instr = __opcode_thumb32_compose(instr, instr2); + } } else { - get_user(instr, (u32 __user *)pc); + if (get_user(instr, (u32 __user *)pc)) + goto die_sig; + instr = __mem_to_opcode_arm(instr); } -#ifdef CONFIG_KPROBES - /* - * It is possible to have recursive kprobes, so we can't call - * the kprobe trap handler with the undef_lock held. - */ - if (instr == KPROBE_BREAKPOINT_INSTRUCTION && !user_mode(regs)) { - kprobe_trap_handler(regs, instr); + if (call_undef_hook(regs, instr) == 0) return; - } -#endif - - 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) { - if (hook->fn(regs, instr) == 0) { - spin_unlock_irqrestore(&undef_lock, flags); - return; - } - } - } - spin_unlock_irqrestore(&undef_lock, flags); +die_sig: #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); + __show_regs(regs); + dump_instr(KERN_INFO, regs); } #endif @@ -381,8 +486,7 @@ 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 && + if ((current->personality & PER_MASK) != PER_LINUX && thread->exec_domain->handler) { thread->exec_domain->handler(n, regs); return regs->ARM_r0; @@ -392,7 +496,7 @@ static int bad_syscall(int n, struct pt_regs *regs) 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); + dump_instr(KERN_ERR, regs); } #endif @@ -407,23 +511,65 @@ static int bad_syscall(int n, struct pt_regs *regs) return regs->ARM_r0; } -static inline void -do_cache_op(unsigned long start, unsigned long end, int flags) +static long do_cache_op_restart(struct restart_block *); + +static inline int +__do_cache_op(unsigned long start, unsigned long end) { - struct vm_area_struct *vma; + int ret; + + do { + unsigned long chunk = min(PAGE_SIZE, end - start); + + if (signal_pending(current)) { + struct thread_info *ti = current_thread_info(); + + ti->restart_block = (struct restart_block) { + .fn = do_cache_op_restart, + }; + + ti->arm_restart_block = (struct arm_restart_block) { + { + .cache = { + .start = start, + .end = end, + }, + }, + }; + + return -ERESTART_RESTARTBLOCK; + } + + ret = flush_cache_user_range(start, start + chunk); + if (ret) + return ret; + cond_resched(); + start += chunk; + } while (start < end); + + return 0; +} + +static long do_cache_op_restart(struct restart_block *unused) +{ + struct arm_restart_block *restart_block; + + restart_block = ¤t_thread_info()->arm_restart_block; + return __do_cache_op(restart_block->cache.start, + restart_block->cache.end); +} + +static inline int +do_cache_op(unsigned long start, unsigned long end, int flags) +{ if (end < start || flags) - return; + return -EINVAL; - 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; + if (!access_ok(VERIFY_READ, start, end - start)) + return -EFAULT; - flush_cache_user_range(vma, start, end); - } + return __do_cache_op(start, end); } /* @@ -469,8 +615,7 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs) * the specified region). */ case NR(cacheflush): - do_cache_op(regs->ARM_r0, regs->ARM_r1, regs->ARM_r2); - return 0; + return do_cache_op(regs->ARM_r0, regs->ARM_r1, regs->ARM_r2); case NR(usr26): if (!(elf_hwcap & HWCAP_26BIT)) @@ -485,18 +630,21 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs) 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 + thread->tp_value[0] = regs->ARM_r0; + if (tls_emu) + return 0; + if (has_tls_reg) { + asm ("mcr p15, 0, %0, c13, c0, 3" + : : "r" (regs->ARM_r0)); + } else { + /* + * 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; + } return 0; #ifdef CONFIG_NEEDS_SYSCALL_FOR_CMPXCHG @@ -511,7 +659,7 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs) * __kuser_cmpxchg code in entry-armv.S should be aware of its * existence. Don't ever use this from user code. */ - case 0xfff0: + case NR(cmpxchg): for (;;) { extern void do_DataAbort(unsigned long addr, unsigned int fsr, struct pt_regs *regs); @@ -530,7 +678,7 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs) if (!pmd_present(*pmd)) goto bad_access; pte = pte_offset_map_lock(mm, pmd, addr, &ptl); - if (!pte_present(*pte) || !pte_dirty(*pte)) { + if (!pte_present(*pte) || !pte_write(*pte) || !pte_dirty(*pte)) { pte_unmap_unlock(pte, ptl); goto bad_access; } @@ -556,7 +704,7 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs) if not implemented, rather than raising SIGILL. This way the calling program can gracefully determine whether a feature is supported. */ - if (no <= 0x7ff) + if ((no & 0xffff) <= 0x7ff) return -ENOSYS; break; } @@ -568,7 +716,7 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs) if (user_debug & UDBG_SYSCALL) { printk("[%d] %s: arm syscall %d\n", task_pid_nr(current), current->comm, no); - dump_instr(regs); + dump_instr("", regs); if (user_mode(regs)) { __show_regs(regs); c_backtrace(regs->ARM_fp, processor_mode(regs)); @@ -600,7 +748,7 @@ 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->uregs[reg] = current_thread_info()->tp_value[0]; regs->ARM_pc += 4; return 0; } @@ -645,7 +793,7 @@ baddataabort(int code, unsigned long instr, struct pt_regs *regs) 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); + dump_instr(KERN_ERR, regs); show_pte(current->mm, addr); } #endif @@ -658,16 +806,6 @@ baddataabort(int code, unsigned long instr, struct pt_regs *regs) 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); @@ -675,19 +813,19 @@ void __readwrite_bug(const char *fn) } EXPORT_SYMBOL(__readwrite_bug); -void __pte_error(const char *file, int line, unsigned long val) +void __pte_error(const char *file, int line, pte_t pte) { - printk("%s:%d: bad pte %08lx.\n", file, line, val); + printk("%s:%d: bad pte %08llx.\n", file, line, (long long)pte_val(pte)); } -void __pmd_error(const char *file, int line, unsigned long val) +void __pmd_error(const char *file, int line, pmd_t pmd) { - printk("%s:%d: bad pmd %08lx.\n", file, line, val); + printk("%s:%d: bad pmd %08llx.\n", file, line, (long long)pmd_val(pmd)); } -void __pgd_error(const char *file, int line, unsigned long val) +void __pgd_error(const char *file, int line, pgd_t pgd) { - printk("%s:%d: bad pgd %08lx.\n", file, line, val); + printk("%s:%d: bad pgd %08llx.\n", file, line, (long long)pgd_val(pgd)); } asmlinkage void __div0(void) @@ -708,28 +846,66 @@ EXPORT_SYMBOL(abort); void __init trap_init(void) { - unsigned long vectors = CONFIG_VECTORS_BASE; - extern char __stubs_start[], __stubs_end[]; - extern char __vectors_start[], __vectors_end[]; + return; +} + +#ifdef CONFIG_KUSER_HELPERS +static void __init kuser_init(void *vectors) +{ extern char __kuser_helper_start[], __kuser_helper_end[]; int kuser_sz = __kuser_helper_end - __kuser_helper_start; + memcpy(vectors + 0x1000 - kuser_sz, __kuser_helper_start, kuser_sz); + + /* + * vectors + 0xfe0 = __kuser_get_tls + * vectors + 0xfe8 = hardware TLS instruction at 0xffff0fe8 + */ + if (tls_emu || has_tls_reg) + memcpy(vectors + 0xfe0, vectors + 0xfe8, 4); +} +#else +static inline void __init kuser_init(void *vectors) +{ +} +#endif + +void __init early_trap_init(void *vectors_base) +{ +#ifndef CONFIG_CPU_V7M + unsigned long vectors = (unsigned long)vectors_base; + extern char __stubs_start[], __stubs_end[]; + extern char __vectors_start[], __vectors_end[]; + unsigned i; + + vectors_page = vectors_base; + + /* + * Poison the vectors page with an undefined instruction. This + * instruction is chosen to be undefined for both ARM and Thumb + * ISAs. The Thumb version is an undefined instruction with a + * branch back to the undefined instruction. + */ + for (i = 0; i < PAGE_SIZE / sizeof(u32); i++) + ((u32 *)vectors_base)[i] = 0xe7fddef1; + /* * 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); + memcpy((void *)vectors + 0x1000, __stubs_start, __stubs_end - __stubs_start); - /* - * 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)); + kuser_init(vectors_base); - flush_icache_range(vectors, vectors + PAGE_SIZE); + flush_icache_range(vectors, vectors + PAGE_SIZE * 2); modify_domain(DOMAIN_USER, DOMAIN_CLIENT); +#else /* ifndef CONFIG_CPU_V7M */ + /* + * on V7-M there is no need to copy the vector table to a dedicated + * memory area. The address is configurable and so a table in the kernel + * image can be used. + */ +#endif } |
