diff options
Diffstat (limited to 'arch/i386/kernel/traps.c')
| -rw-r--r-- | arch/i386/kernel/traps.c | 1120 |
1 files changed, 0 insertions, 1120 deletions
diff --git a/arch/i386/kernel/traps.c b/arch/i386/kernel/traps.c deleted file mode 100644 index c34d1bfc516..00000000000 --- a/arch/i386/kernel/traps.c +++ /dev/null @@ -1,1120 +0,0 @@ -/* - * linux/arch/i386/traps.c - * - * Copyright (C) 1991, 1992 Linus Torvalds - * - * Pentium III FXSR, SSE support - * Gareth Hughes <gareth@valinux.com>, May 2000 - */ - -/* - * 'Traps.c' handles hardware traps and faults after we have saved some - * state in 'asm.s'. - */ -#include <linux/config.h> -#include <linux/sched.h> -#include <linux/kernel.h> -#include <linux/string.h> -#include <linux/errno.h> -#include <linux/timer.h> -#include <linux/mm.h> -#include <linux/init.h> -#include <linux/delay.h> -#include <linux/spinlock.h> -#include <linux/interrupt.h> -#include <linux/highmem.h> -#include <linux/kallsyms.h> -#include <linux/ptrace.h> -#include <linux/utsname.h> -#include <linux/kprobes.h> -#include <linux/kexec.h> - -#ifdef CONFIG_EISA -#include <linux/ioport.h> -#include <linux/eisa.h> -#endif - -#ifdef CONFIG_MCA -#include <linux/mca.h> -#endif - -#include <asm/processor.h> -#include <asm/system.h> -#include <asm/uaccess.h> -#include <asm/io.h> -#include <asm/atomic.h> -#include <asm/debugreg.h> -#include <asm/desc.h> -#include <asm/i387.h> -#include <asm/nmi.h> - -#include <asm/smp.h> -#include <asm/arch_hooks.h> -#include <asm/kdebug.h> - -#include <linux/module.h> - -#include "mach_traps.h" - -asmlinkage int system_call(void); - -struct desc_struct default_ldt[] = { { 0, 0 }, { 0, 0 }, { 0, 0 }, - { 0, 0 }, { 0, 0 } }; - -/* Do we ignore FPU interrupts ? */ -char ignore_fpu_irq = 0; - -/* - * The IDT has to be page-aligned to simplify the Pentium - * F0 0F bug workaround.. We have a special link segment - * for this. - */ -struct desc_struct idt_table[256] __attribute__((__section__(".data.idt"))) = { {0, 0}, }; - -asmlinkage void divide_error(void); -asmlinkage void debug(void); -asmlinkage void nmi(void); -asmlinkage void int3(void); -asmlinkage void overflow(void); -asmlinkage void bounds(void); -asmlinkage void invalid_op(void); -asmlinkage void device_not_available(void); -asmlinkage void coprocessor_segment_overrun(void); -asmlinkage void invalid_TSS(void); -asmlinkage void segment_not_present(void); -asmlinkage void stack_segment(void); -asmlinkage void general_protection(void); -asmlinkage void page_fault(void); -asmlinkage void coprocessor_error(void); -asmlinkage void simd_coprocessor_error(void); -asmlinkage void alignment_check(void); -asmlinkage void spurious_interrupt_bug(void); -asmlinkage void machine_check(void); - -static int kstack_depth_to_print = 24; -struct notifier_block *i386die_chain; -static DEFINE_SPINLOCK(die_notifier_lock); - -int register_die_notifier(struct notifier_block *nb) -{ - int err = 0; - unsigned long flags; - spin_lock_irqsave(&die_notifier_lock, flags); - err = notifier_chain_register(&i386die_chain, nb); - spin_unlock_irqrestore(&die_notifier_lock, flags); - return err; -} -EXPORT_SYMBOL(register_die_notifier); - -static inline int valid_stack_ptr(struct thread_info *tinfo, void *p) -{ - return p > (void *)tinfo && - p < (void *)tinfo + THREAD_SIZE - 3; -} - -static inline unsigned long print_context_stack(struct thread_info *tinfo, - unsigned long *stack, unsigned long ebp) -{ - unsigned long addr; - -#ifdef CONFIG_FRAME_POINTER - while (valid_stack_ptr(tinfo, (void *)ebp)) { - addr = *(unsigned long *)(ebp + 4); - printk(" [<%08lx>] ", addr); - print_symbol("%s", addr); - printk("\n"); - ebp = *(unsigned long *)ebp; - } -#else - while (valid_stack_ptr(tinfo, stack)) { - addr = *stack++; - if (__kernel_text_address(addr)) { - printk(" [<%08lx>]", addr); - print_symbol(" %s", addr); - printk("\n"); - } - } -#endif - return ebp; -} - -void show_trace(struct task_struct *task, unsigned long * stack) -{ - unsigned long ebp; - - if (!task) - task = current; - - if (task == current) { - /* Grab ebp right from our regs */ - asm ("movl %%ebp, %0" : "=r" (ebp) : ); - } else { - /* ebp is the last reg pushed by switch_to */ - ebp = *(unsigned long *) task->thread.esp; - } - - while (1) { - struct thread_info *context; - context = (struct thread_info *) - ((unsigned long)stack & (~(THREAD_SIZE - 1))); - ebp = print_context_stack(context, stack, ebp); - stack = (unsigned long*)context->previous_esp; - if (!stack) - break; - printk(" =======================\n"); - } -} - -void show_stack(struct task_struct *task, unsigned long *esp) -{ - unsigned long *stack; - int i; - - if (esp == NULL) { - if (task) - esp = (unsigned long*)task->thread.esp; - else - esp = (unsigned long *)&esp; - } - - stack = esp; - for(i = 0; i < kstack_depth_to_print; i++) { - if (kstack_end(stack)) - break; - if (i && ((i % 8) == 0)) - printk("\n "); - printk("%08lx ", *stack++); - } - printk("\nCall Trace:\n"); - show_trace(task, esp); -} - -/* - * The architecture-independent dump_stack generator - */ -void dump_stack(void) -{ - unsigned long stack; - - show_trace(current, &stack); -} - -EXPORT_SYMBOL(dump_stack); - -void show_registers(struct pt_regs *regs) -{ - int i; - int in_kernel = 1; - unsigned long esp; - unsigned short ss; - - esp = (unsigned long) (®s->esp); - savesegment(ss, ss); - if (user_mode(regs)) { - in_kernel = 0; - esp = regs->esp; - ss = regs->xss & 0xffff; - } - print_modules(); - printk("CPU: %d\nEIP: %04x:[<%08lx>] %s VLI\nEFLAGS: %08lx" - " (%s) \n", - smp_processor_id(), 0xffff & regs->xcs, regs->eip, - print_tainted(), regs->eflags, system_utsname.release); - print_symbol("EIP is at %s\n", regs->eip); - printk("eax: %08lx ebx: %08lx ecx: %08lx edx: %08lx\n", - regs->eax, regs->ebx, regs->ecx, regs->edx); - printk("esi: %08lx edi: %08lx ebp: %08lx esp: %08lx\n", - regs->esi, regs->edi, regs->ebp, esp); - printk("ds: %04x es: %04x ss: %04x\n", - regs->xds & 0xffff, regs->xes & 0xffff, ss); - printk("Process %s (pid: %d, threadinfo=%p task=%p)", - current->comm, current->pid, current_thread_info(), current); - /* - * When in-kernel, we also print out the stack and code at the - * time of the fault.. - */ - if (in_kernel) { - u8 __user *eip; - - printk("\nStack: "); - show_stack(NULL, (unsigned long*)esp); - - printk("Code: "); - - eip = (u8 __user *)regs->eip - 43; - for (i = 0; i < 64; i++, eip++) { - unsigned char c; - - if (eip < (u8 __user *)PAGE_OFFSET || __get_user(c, eip)) { - printk(" Bad EIP value."); - break; - } - if (eip == (u8 __user *)regs->eip) - printk("<%02x> ", c); - else - printk("%02x ", c); - } - } - printk("\n"); -} - -static void handle_BUG(struct pt_regs *regs) -{ - unsigned short ud2; - unsigned short line; - char *file; - char c; - unsigned long eip; - - eip = regs->eip; - - if (eip < PAGE_OFFSET) - goto no_bug; - if (__get_user(ud2, (unsigned short __user *)eip)) - goto no_bug; - if (ud2 != 0x0b0f) - goto no_bug; - if (__get_user(line, (unsigned short __user *)(eip + 2))) - goto bug; - if (__get_user(file, (char * __user *)(eip + 4)) || - (unsigned long)file < PAGE_OFFSET || __get_user(c, file)) - file = "<bad filename>"; - - printk("------------[ cut here ]------------\n"); - printk(KERN_ALERT "kernel BUG at %s:%d!\n", file, line); - -no_bug: - return; - - /* Here we know it was a BUG but file-n-line is unavailable */ -bug: - printk("Kernel BUG\n"); -} - -/* This is gone through when something in the kernel - * has done something bad and is about to be terminated. -*/ -void die(const char * str, struct pt_regs * regs, long err) -{ - static struct { - spinlock_t lock; - u32 lock_owner; - int lock_owner_depth; - } die = { - .lock = SPIN_LOCK_UNLOCKED, - .lock_owner = -1, - .lock_owner_depth = 0 - }; - static int die_counter; - - if (die.lock_owner != raw_smp_processor_id()) { - console_verbose(); - spin_lock_irq(&die.lock); - die.lock_owner = smp_processor_id(); - die.lock_owner_depth = 0; - bust_spinlocks(1); - } - - if (++die.lock_owner_depth < 3) { - int nl = 0; - handle_BUG(regs); - printk(KERN_ALERT "%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter); -#ifdef CONFIG_PREEMPT - printk("PREEMPT "); - nl = 1; -#endif -#ifdef CONFIG_SMP - printk("SMP "); - nl = 1; -#endif -#ifdef CONFIG_DEBUG_PAGEALLOC - printk("DEBUG_PAGEALLOC"); - nl = 1; -#endif - if (nl) - printk("\n"); - notify_die(DIE_OOPS, (char *)str, regs, err, 255, SIGSEGV); - show_registers(regs); - } else - printk(KERN_ERR "Recursive die() failure, output suppressed\n"); - - bust_spinlocks(0); - die.lock_owner = -1; - spin_unlock_irq(&die.lock); - - if (kexec_should_crash(current)) - crash_kexec(regs); - - if (in_interrupt()) - panic("Fatal exception in interrupt"); - - if (panic_on_oops) { - printk(KERN_EMERG "Fatal exception: panic in 5 seconds\n"); - ssleep(5); - panic("Fatal exception"); - } - do_exit(SIGSEGV); -} - -static inline void die_if_kernel(const char * str, struct pt_regs * regs, long err) -{ - if (!user_mode_vm(regs)) - die(str, regs, err); -} - -static void __kprobes do_trap(int trapnr, int signr, char *str, int vm86, - struct pt_regs * regs, long error_code, - siginfo_t *info) -{ - struct task_struct *tsk = current; - tsk->thread.error_code = error_code; - tsk->thread.trap_no = trapnr; - - if (regs->eflags & VM_MASK) { - if (vm86) - goto vm86_trap; - goto trap_signal; - } - - if (!user_mode(regs)) - goto kernel_trap; - - trap_signal: { - if (info) - force_sig_info(signr, info, tsk); - else - force_sig(signr, tsk); - return; - } - - kernel_trap: { - if (!fixup_exception(regs)) - die(str, regs, error_code); - return; - } - - vm86_trap: { - int ret = handle_vm86_trap((struct kernel_vm86_regs *) regs, error_code, trapnr); - if (ret) goto trap_signal; - return; - } -} - -#define DO_ERROR(trapnr, signr, str, name) \ -fastcall void do_##name(struct pt_regs * regs, long error_code) \ -{ \ - if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \ - == NOTIFY_STOP) \ - return; \ - do_trap(trapnr, signr, str, 0, regs, error_code, NULL); \ -} - -#define DO_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr) \ -fastcall void do_##name(struct pt_regs * regs, long error_code) \ -{ \ - siginfo_t info; \ - info.si_signo = signr; \ - info.si_errno = 0; \ - info.si_code = sicode; \ - info.si_addr = (void __user *)siaddr; \ - if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \ - == NOTIFY_STOP) \ - return; \ - do_trap(trapnr, signr, str, 0, regs, error_code, &info); \ -} - -#define DO_VM86_ERROR(trapnr, signr, str, name) \ -fastcall void do_##name(struct pt_regs * regs, long error_code) \ -{ \ - if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \ - == NOTIFY_STOP) \ - return; \ - do_trap(trapnr, signr, str, 1, regs, error_code, NULL); \ -} - -#define DO_VM86_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr) \ -fastcall void do_##name(struct pt_regs * regs, long error_code) \ -{ \ - siginfo_t info; \ - info.si_signo = signr; \ - info.si_errno = 0; \ - info.si_code = sicode; \ - info.si_addr = (void __user *)siaddr; \ - if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \ - == NOTIFY_STOP) \ - return; \ - do_trap(trapnr, signr, str, 1, regs, error_code, &info); \ -} - -DO_VM86_ERROR_INFO( 0, SIGFPE, "divide error", divide_error, FPE_INTDIV, regs->eip) -#ifndef CONFIG_KPROBES -DO_VM86_ERROR( 3, SIGTRAP, "int3", int3) -#endif -DO_VM86_ERROR( 4, SIGSEGV, "overflow", overflow) -DO_VM86_ERROR( 5, SIGSEGV, "bounds", bounds) -DO_ERROR_INFO( 6, SIGILL, "invalid operand", invalid_op, ILL_ILLOPN, regs->eip) -DO_ERROR( 9, SIGFPE, "coprocessor segment overrun", coprocessor_segment_overrun) -DO_ERROR(10, SIGSEGV, "invalid TSS", invalid_TSS) -DO_ERROR(11, SIGBUS, "segment not present", segment_not_present) -DO_ERROR(12, SIGBUS, "stack segment", stack_segment) -DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, 0) -DO_ERROR_INFO(32, SIGSEGV, "iret exception", iret_error, ILL_BADSTK, 0) - -fastcall void __kprobes do_general_protection(struct pt_regs * regs, - long error_code) -{ - int cpu = get_cpu(); - struct tss_struct *tss = &per_cpu(init_tss, cpu); - struct thread_struct *thread = ¤t->thread; - - /* - * Perform the lazy TSS's I/O bitmap copy. If the TSS has an - * invalid offset set (the LAZY one) and the faulting thread has - * a valid I/O bitmap pointer, we copy the I/O bitmap in the TSS - * and we set the offset field correctly. Then we let the CPU to - * restart the faulting instruction. - */ - if (tss->io_bitmap_base == INVALID_IO_BITMAP_OFFSET_LAZY && - thread->io_bitmap_ptr) { - memcpy(tss->io_bitmap, thread->io_bitmap_ptr, - thread->io_bitmap_max); - /* - * If the previously set map was extending to higher ports - * than the current one, pad extra space with 0xff (no access). - */ - if (thread->io_bitmap_max < tss->io_bitmap_max) - memset((char *) tss->io_bitmap + - thread->io_bitmap_max, 0xff, - tss->io_bitmap_max - thread->io_bitmap_max); - tss->io_bitmap_max = thread->io_bitmap_max; - tss->io_bitmap_base = IO_BITMAP_OFFSET; - tss->io_bitmap_owner = thread; - put_cpu(); - return; - } - put_cpu(); - - current->thread.error_code = error_code; - current->thread.trap_no = 13; - - if (regs->eflags & VM_MASK) - goto gp_in_vm86; - - if (!user_mode(regs)) - goto gp_in_kernel; - - current->thread.error_code = error_code; - current->thread.trap_no = 13; - force_sig(SIGSEGV, current); - return; - -gp_in_vm86: - local_irq_enable(); - handle_vm86_fault((struct kernel_vm86_regs *) regs, error_code); - return; - -gp_in_kernel: - if (!fixup_exception(regs)) { - if (notify_die(DIE_GPF, "general protection fault", regs, - error_code, 13, SIGSEGV) == NOTIFY_STOP) - return; - die("general protection fault", regs, error_code); - } -} - -static void mem_parity_error(unsigned char reason, struct pt_regs * regs) -{ - printk("Uhhuh. NMI received. Dazed and confused, but trying to continue\n"); - printk("You probably have a hardware problem with your RAM chips\n"); - - /* Clear and disable the memory parity error line. */ - clear_mem_error(reason); -} - -static void io_check_error(unsigned char reason, struct pt_regs * regs) -{ - unsigned long i; - - printk("NMI: IOCK error (debug interrupt?)\n"); - show_registers(regs); - - /* Re-enable the IOCK line, wait for a few seconds */ - reason = (reason & 0xf) | 8; - outb(reason, 0x61); - i = 2000; - while (--i) udelay(1000); - reason &= ~8; - outb(reason, 0x61); -} - -static void unknown_nmi_error(unsigned char reason, struct pt_regs * regs) -{ -#ifdef CONFIG_MCA - /* Might actually be able to figure out what the guilty party - * is. */ - if( MCA_bus ) { - mca_handle_nmi(); - return; - } -#endif - printk("Uhhuh. NMI received for unknown reason %02x on CPU %d.\n", - reason, smp_processor_id()); - printk("Dazed and confused, but trying to continue\n"); - printk("Do you have a strange power saving mode enabled?\n"); -} - -static DEFINE_SPINLOCK(nmi_print_lock); - -void die_nmi (struct pt_regs *regs, const char *msg) -{ - if (notify_die(DIE_NMIWATCHDOG, msg, regs, 0, 0, SIGINT) == - NOTIFY_STOP) - return; - - spin_lock(&nmi_print_lock); - /* - * We are in trouble anyway, lets at least try - * to get a message out. - */ - bust_spinlocks(1); - printk(msg); - printk(" on CPU%d, eip %08lx, registers:\n", - smp_processor_id(), regs->eip); - show_registers(regs); - printk("console shuts up ...\n"); - console_silent(); - spin_unlock(&nmi_print_lock); - bust_spinlocks(0); - - /* If we are in kernel we are probably nested up pretty bad - * and might aswell get out now while we still can. - */ - if (!user_mode(regs)) { - current->thread.trap_no = 2; - crash_kexec(regs); - } - - do_exit(SIGSEGV); -} - -static void default_do_nmi(struct pt_regs * regs) -{ - unsigned char reason = 0; - - /* Only the BSP gets external NMIs from the system. */ - if (!smp_processor_id()) - reason = get_nmi_reason(); - - if (!(reason & 0xc0)) { - if (notify_die(DIE_NMI_IPI, "nmi_ipi", regs, reason, 0, SIGINT) - == NOTIFY_STOP) - return; -#ifdef CONFIG_X86_LOCAL_APIC - /* - * Ok, so this is none of the documented NMI sources, - * so it must be the NMI watchdog. - */ - if (nmi_watchdog) { - nmi_watchdog_tick(regs); - return; - } -#endif - unknown_nmi_error(reason, regs); - return; - } - if (notify_die(DIE_NMI, "nmi", regs, reason, 0, SIGINT) == NOTIFY_STOP) - return; - if (reason & 0x80) - mem_parity_error(reason, regs); - if (reason & 0x40) - io_check_error(reason, regs); - /* - * Reassert NMI in case it became active meanwhile - * as it's edge-triggered. - */ - reassert_nmi(); -} - -static int dummy_nmi_callback(struct pt_regs * regs, int cpu) -{ - return 0; -} - -static nmi_callback_t nmi_callback = dummy_nmi_callback; - -fastcall void do_nmi(struct pt_regs * regs, long error_code) -{ - int cpu; - - nmi_enter(); - - cpu = smp_processor_id(); - -#ifdef CONFIG_HOTPLUG_CPU - if (!cpu_online(cpu)) { - nmi_exit(); - return; - } -#endif - - ++nmi_count(cpu); - - if (!rcu_dereference(nmi_callback)(regs, cpu)) - default_do_nmi(regs); - - nmi_exit(); -} - -void set_nmi_callback(nmi_callback_t callback) -{ - rcu_assign_pointer(nmi_callback, callback); -} -EXPORT_SYMBOL_GPL(set_nmi_callback); - -void unset_nmi_callback(void) -{ - nmi_callback = dummy_nmi_callback; -} -EXPORT_SYMBOL_GPL(unset_nmi_callback); - -#ifdef CONFIG_KPROBES -fastcall void __kprobes do_int3(struct pt_regs *regs, long error_code) -{ - if (notify_die(DIE_INT3, "int3", regs, error_code, 3, SIGTRAP) - == NOTIFY_STOP) - return; - /* This is an interrupt gate, because kprobes wants interrupts - disabled. Normal trap handlers don't. */ - restore_interrupts(regs); - do_trap(3, SIGTRAP, "int3", 1, regs, error_code, NULL); -} -#endif - -/* - * Our handling of the processor debug registers is non-trivial. - * We do not clear them on entry and exit from the kernel. Therefore - * it is possible to get a watchpoint trap here from inside the kernel. - * However, the code in ./ptrace.c has ensured that the user can - * only set watchpoints on userspace addresses. Therefore the in-kernel - * watchpoint trap can only occur in code which is reading/writing - * from user space. Such code must not hold kernel locks (since it - * can equally take a page fault), therefore it is safe to call - * force_sig_info even though that claims and releases locks. - * - * Code in ./signal.c ensures that the debug control register - * is restored before we deliver any signal, and therefore that - * user code runs with the correct debug control register even though - * we clear it here. - * - * Being careful here means that we don't have to be as careful in a - * lot of more complicated places (task switching can be a bit lazy - * about restoring all the debug state, and ptrace doesn't have to - * find every occurrence of the TF bit that could be saved away even - * by user code) - */ -fastcall void __kprobes do_debug(struct pt_regs * regs, long error_code) -{ - unsigned int condition; - struct task_struct *tsk = current; - - get_debugreg(condition, 6); - - if (notify_die(DIE_DEBUG, "debug", regs, condition, error_code, - SIGTRAP) == NOTIFY_STOP) - return; - /* It's safe to allow irq's after DR6 has been saved */ - if (regs->eflags & X86_EFLAGS_IF) - local_irq_enable(); - - /* Mask out spurious debug traps due to lazy DR7 setting */ - if (condition & (DR_TRAP0|DR_TRAP1|DR_TRAP2|DR_TRAP3)) { - if (!tsk->thread.debugreg[7]) - goto clear_dr7; - } - - if (regs->eflags & VM_MASK) - goto debug_vm86; - - /* Save debug status register where ptrace can see it */ - tsk->thread.debugreg[6] = condition; - - /* - * Single-stepping through TF: make sure we ignore any events in - * kernel space (but re-enable TF when returning to user mode). - */ - if (condition & DR_STEP) { - /* - * We already checked v86 mode above, so we can - * check for kernel mode by just checking the CPL - * of CS. - */ - if (!user_mode(regs)) - goto clear_TF_reenable; - } - - /* Ok, finally something we can handle */ - send_sigtrap(tsk, regs, error_code); - - /* Disable additional traps. They'll be re-enabled when - * the signal is delivered. - */ -clear_dr7: - set_debugreg(0, 7); - return; - -debug_vm86: - handle_vm86_trap((struct kernel_vm86_regs *) regs, error_code, 1); - return; - -clear_TF_reenable: - set_tsk_thread_flag(tsk, TIF_SINGLESTEP); - regs->eflags &= ~TF_MASK; - return; -} - -/* - * Note that we play around with the 'TS' bit in an attempt to get - * the correct behaviour even in the presence of the asynchronous - * IRQ13 behaviour - */ -void math_error(void __user *eip) -{ - struct task_struct * task; - siginfo_t info; - unsigned short cwd, swd; - - /* - * Save the info for the exception handler and clear the error. - */ - task = current; - save_init_fpu(task); - task->thread.trap_no = 16; - task->thread.error_code = 0; - info.si_signo = SIGFPE; - info.si_errno = 0; - info.si_code = __SI_FAULT; - info.si_addr = eip; - /* - * (~cwd & swd) will mask out exceptions that are not set to unmasked - * status. 0x3f is the exception bits in these regs, 0x200 is the - * C1 reg you need in case of a stack fault, 0x040 is the stack - * fault bit. We should only be taking one exception at a time, - * so if this combination doesn't produce any single exception, - * then we have a bad program that isn't syncronizing its FPU usage - * and it will suffer the consequences since we won't be able to - * fully reproduce the context of the exception - */ - cwd = get_fpu_cwd(task); - swd = get_fpu_swd(task); - switch (swd & ~cwd & 0x3f) { - case 0x000: /* No unmasked exception */ - return; - default: /* Multiple exceptions */ - break; - case 0x001: /* Invalid Op */ - /* - * swd & 0x240 == 0x040: Stack Underflow - * swd & 0x240 == 0x240: Stack Overflow - * User must clear the SF bit (0x40) if set - */ - info.si_code = FPE_FLTINV; - break; - case 0x002: /* Denormalize */ - case 0x010: /* Underflow */ - info.si_code = FPE_FLTUND; - break; - case 0x004: /* Zero Divide */ - info.si_code = FPE_FLTDIV; - break; - case 0x008: /* Overflow */ - info.si_code = FPE_FLTOVF; - break; - case 0x020: /* Precision */ - info.si_code = FPE_FLTRES; - break; - } - force_sig_info(SIGFPE, &info, task); -} - -fastcall void do_coprocessor_error(struct pt_regs * regs, long error_code) -{ - ignore_fpu_irq = 1; - math_error((void __user *)regs->eip); -} - -static void simd_math_error(void __user *eip) -{ - struct task_struct * task; - siginfo_t info; - unsigned short mxcsr; - - /* - * Save the info for the exception handler and clear the error. - */ - task = current; - save_init_fpu(task); - task->thread.trap_no = 19; - task->thread.error_code = 0; - info.si_signo = SIGFPE; - info.si_errno = 0; - info.si_code = __SI_FAULT; - info.si_addr = eip; - /* - * The SIMD FPU exceptions are handled a little differently, as there - * is only a single status/control register. Thus, to determine which - * unmasked exception was caught we must mask the exception mask bits - * at 0x1f80, and then use these to mask the exception bits at 0x3f. - */ - mxcsr = get_fpu_mxcsr(task); - switch (~((mxcsr & 0x1f80) >> 7) & (mxcsr & 0x3f)) { - case 0x000: - default: - break; - case 0x001: /* Invalid Op */ - info.si_code = FPE_FLTINV; - break; - case 0x002: /* Denormalize */ - case 0x010: /* Underflow */ - info.si_code = FPE_FLTUND; - break; - case 0x004: /* Zero Divide */ - info.si_code = FPE_FLTDIV; - break; - case 0x008: /* Overflow */ - info.si_code = FPE_FLTOVF; - break; - case 0x020: /* Precision */ - info.si_code = FPE_FLTRES; - break; - } - force_sig_info(SIGFPE, &info, task); -} - -fastcall void do_simd_coprocessor_error(struct pt_regs * regs, - long error_code) -{ - if (cpu_has_xmm) { - /* Handle SIMD FPU exceptions on PIII+ processors. */ - ignore_fpu_irq = 1; - simd_math_error((void __user *)regs->eip); - } else { - /* - * Handle strange cache flush from user space exception - * in all other cases. This is undocumented behaviour. - */ - if (regs->eflags & VM_MASK) { - handle_vm86_fault((struct kernel_vm86_regs *)regs, - error_code); - return; - } - current->thread.trap_no = 19; - current->thread.error_code = error_code; - die_if_kernel("cache flush denied", regs, error_code); - force_sig(SIGSEGV, current); - } -} - -fastcall void do_spurious_interrupt_bug(struct pt_regs * regs, - long error_code) -{ -#if 0 - /* No need to warn about this any longer. */ - printk("Ignoring P6 Local APIC Spurious Interrupt Bug...\n"); -#endif -} - -fastcall void setup_x86_bogus_stack(unsigned char * stk) -{ - unsigned long *switch16_ptr, *switch32_ptr; - struct pt_regs *regs; - unsigned long stack_top, stack_bot; - unsigned short iret_frame16_off; - int cpu = smp_processor_id(); - /* reserve the space on 32bit stack for the magic switch16 pointer */ - memmove(stk, stk + 8, sizeof(struct pt_regs)); - switch16_ptr = (unsigned long *)(stk + sizeof(struct pt_regs)); - regs = (struct pt_regs *)stk; - /* now the switch32 on 16bit stack */ - stack_bot = (unsigned long)&per_cpu(cpu_16bit_stack, cpu); - stack_top = stack_bot + CPU_16BIT_STACK_SIZE; - switch32_ptr = (unsigned long *)(stack_top - 8); - iret_frame16_off = CPU_16BIT_STACK_SIZE - 8 - 20; - /* copy iret frame on 16bit stack */ - memcpy((void *)(stack_bot + iret_frame16_off), ®s->eip, 20); - /* fill in the switch pointers */ - switch16_ptr[0] = (regs->esp & 0xffff0000) | iret_frame16_off; - switch16_ptr[1] = __ESPFIX_SS; - switch32_ptr[0] = (unsigned long)stk + sizeof(struct pt_regs) + - 8 - CPU_16BIT_STACK_SIZE; - switch32_ptr[1] = __KERNEL_DS; -} - -fastcall unsigned char * fixup_x86_bogus_stack(unsigned short sp) -{ - unsigned long *switch32_ptr; - unsigned char *stack16, *stack32; - unsigned long stack_top, stack_bot; - int len; - int cpu = smp_processor_id(); - stack_bot = (unsigned long)&per_cpu(cpu_16bit_stack, cpu); - stack_top = stack_bot + CPU_16BIT_STACK_SIZE; - switch32_ptr = (unsigned long *)(stack_top - 8); - /* copy the data from 16bit stack to 32bit stack */ - len = CPU_16BIT_STACK_SIZE - 8 - sp; - stack16 = (unsigned char *)(stack_bot + sp); - stack32 = (unsigned char *) - (switch32_ptr[0] + CPU_16BIT_STACK_SIZE - 8 - len); - memcpy(stack32, stack16, len); - return stack32; -} - -/* - * 'math_state_restore()' saves the current math information in the - * old math state array, and gets the new ones from the current task - * - * Careful.. There are problems with IBM-designed IRQ13 behaviour. - * Don't touch unless you *really* know how it works. - * - * Must be called with kernel preemption disabled (in this case, - * local interrupts are disabled at the call-site in entry.S). - */ -asmlinkage void math_state_restore(struct pt_regs regs) -{ - struct thread_info *thread = current_thread_info(); - struct task_struct *tsk = thread->task; - - clts(); /* Allow maths ops (or we recurse) */ - if (!tsk_used_math(tsk)) - init_fpu(tsk); - restore_fpu(tsk); - thread->status |= TS_USEDFPU; /* So we fnsave on switch_to() */ -} - -#ifndef CONFIG_MATH_EMULATION - -asmlinkage void math_emulate(long arg) -{ - printk("math-emulation not enabled and no coprocessor found.\n"); - printk("killing %s.\n",current->comm); - force_sig(SIGFPE,current); - schedule(); -} - -#endif /* CONFIG_MATH_EMULATION */ - -#ifdef CONFIG_X86_F00F_BUG -void __init trap_init_f00f_bug(void) -{ - __set_fixmap(FIX_F00F_IDT, __pa(&idt_table), PAGE_KERNEL_RO); - - /* - * Update the IDT descriptor and reload the IDT so that - * it uses the read-only mapped virtual address. - */ - idt_descr.address = fix_to_virt(FIX_F00F_IDT); - load_idt(&idt_descr); -} -#endif - -#define _set_gate(gate_addr,type,dpl,addr,seg) \ -do { \ - int __d0, __d1; \ - __asm__ __volatile__ ("movw %%dx,%%ax\n\t" \ - "movw %4,%%dx\n\t" \ - "movl %%eax,%0\n\t" \ - "movl %%edx,%1" \ - :"=m" (*((long *) (gate_addr))), \ - "=m" (*(1+(long *) (gate_addr))), "=&a" (__d0), "=&d" (__d1) \ - :"i" ((short) (0x8000+(dpl<<13)+(type<<8))), \ - "3" ((char *) (addr)),"2" ((seg) << 16)); \ -} while (0) - - -/* - * This needs to use 'idt_table' rather than 'idt', and - * thus use the _nonmapped_ version of the IDT, as the - * Pentium F0 0F bugfix can have resulted in the mapped - * IDT being write-protected. - */ -void set_intr_gate(unsigned int n, void *addr) -{ - _set_gate(idt_table+n,14,0,addr,__KERNEL_CS); -} - -/* - * This routine sets up an interrupt gate at directory privilege level 3. - */ -static inline void set_system_intr_gate(unsigned int n, void *addr) -{ - _set_gate(idt_table+n, 14, 3, addr, __KERNEL_CS); -} - -static void __init set_trap_gate(unsigned int n, void *addr) -{ - _set_gate(idt_table+n,15,0,addr,__KERNEL_CS); -} - -static void __init set_system_gate(unsigned int n, void *addr) -{ - _set_gate(idt_table+n,15,3,addr,__KERNEL_CS); -} - -static void __init set_task_gate(unsigned int n, unsigned int gdt_entry) -{ - _set_gate(idt_table+n,5,0,0,(gdt_entry<<3)); -} - - -void __init trap_init(void) -{ -#ifdef CONFIG_EISA - void __iomem *p = ioremap(0x0FFFD9, 4); - if (readl(p) == 'E'+('I'<<8)+('S'<<16)+('A'<<24)) { - EISA_bus = 1; - } - iounmap(p); -#endif - -#ifdef CONFIG_X86_LOCAL_APIC - init_apic_mappings(); -#endif - - set_trap_gate(0,÷_error); - set_intr_gate(1,&debug); - set_intr_gate(2,&nmi); - set_system_intr_gate(3, &int3); /* int3-5 can be called from all */ - set_system_gate(4,&overflow); - set_system_gate(5,&bounds); - set_trap_gate(6,&invalid_op); - set_trap_gate(7,&device_not_available); - set_task_gate(8,GDT_ENTRY_DOUBLEFAULT_TSS); - set_trap_gate(9,&coprocessor_segment_overrun); - set_trap_gate(10,&invalid_TSS); - set_trap_gate(11,&segment_not_present); - set_trap_gate(12,&stack_segment); - set_trap_gate(13,&general_protection); - set_intr_gate(14,&page_fault); - set_trap_gate(15,&spurious_interrupt_bug); - set_trap_gate(16,&coprocessor_error); - set_trap_gate(17,&alignment_check); -#ifdef CONFIG_X86_MCE - set_trap_gate(18,&machine_check); -#endif - set_trap_gate(19,&simd_coprocessor_error); - - set_system_gate(SYSCALL_VECTOR,&system_call); - - /* - * Should be a barrier for any external CPU state. - */ - cpu_init(); - - trap_init_hook(); -} - -static int __init kstack_setup(char *s) -{ - kstack_depth_to_print = simple_strtoul(s, NULL, 0); - return 0; -} -__setup("kstack=", kstack_setup); |