diff options
Diffstat (limited to 'arch/x86_64/kernel/traps.c')
| -rw-r--r-- | arch/x86_64/kernel/traps.c | 1138 |
1 files changed, 0 insertions, 1138 deletions
diff --git a/arch/x86_64/kernel/traps.c b/arch/x86_64/kernel/traps.c deleted file mode 100644 index 03888420775d..000000000000 --- a/arch/x86_64/kernel/traps.c +++ /dev/null @@ -1,1138 +0,0 @@ -/* - * linux/arch/x86-64/traps.c - * - * Copyright (C) 1991, 1992 Linus Torvalds - * Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs - * - * 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 'entry.S'. - */ -#include <linux/sched.h> -#include <linux/kernel.h> -#include <linux/string.h> -#include <linux/errno.h> -#include <linux/ptrace.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/kallsyms.h> -#include <linux/module.h> -#include <linux/moduleparam.h> -#include <linux/nmi.h> -#include <linux/kprobes.h> -#include <linux/kexec.h> -#include <linux/unwind.h> -#include <linux/uaccess.h> -#include <linux/bug.h> -#include <linux/kdebug.h> - -#if defined(CONFIG_EDAC) -#include <linux/edac.h> -#endif - -#include <asm/system.h> -#include <asm/io.h> -#include <asm/atomic.h> -#include <asm/debugreg.h> -#include <asm/desc.h> -#include <asm/i387.h> -#include <asm/processor.h> -#include <asm/unwind.h> -#include <asm/smp.h> -#include <asm/pgalloc.h> -#include <asm/pda.h> -#include <asm/proto.h> -#include <asm/nmi.h> -#include <asm/stacktrace.h> - -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 double_fault(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 reserved(void); -asmlinkage void alignment_check(void); -asmlinkage void machine_check(void); -asmlinkage void spurious_interrupt_bug(void); - -static inline void conditional_sti(struct pt_regs *regs) -{ - if (regs->eflags & X86_EFLAGS_IF) - local_irq_enable(); -} - -static inline void preempt_conditional_sti(struct pt_regs *regs) -{ - preempt_disable(); - if (regs->eflags & X86_EFLAGS_IF) - local_irq_enable(); -} - -static inline void preempt_conditional_cli(struct pt_regs *regs) -{ - if (regs->eflags & X86_EFLAGS_IF) - local_irq_disable(); - /* Make sure to not schedule here because we could be running - on an exception stack. */ - preempt_enable_no_resched(); -} - -int kstack_depth_to_print = 12; - -#ifdef CONFIG_KALLSYMS -void printk_address(unsigned long address) -{ - unsigned long offset = 0, symsize; - const char *symname; - char *modname; - char *delim = ":"; - char namebuf[128]; - - symname = kallsyms_lookup(address, &symsize, &offset, - &modname, namebuf); - if (!symname) { - printk(" [<%016lx>]\n", address); - return; - } - if (!modname) - modname = delim = ""; - printk(" [<%016lx>] %s%s%s%s+0x%lx/0x%lx\n", - address, delim, modname, delim, symname, offset, symsize); -} -#else -void printk_address(unsigned long address) -{ - printk(" [<%016lx>]\n", address); -} -#endif - -static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack, - unsigned *usedp, char **idp) -{ - static char ids[][8] = { - [DEBUG_STACK - 1] = "#DB", - [NMI_STACK - 1] = "NMI", - [DOUBLEFAULT_STACK - 1] = "#DF", - [STACKFAULT_STACK - 1] = "#SS", - [MCE_STACK - 1] = "#MC", -#if DEBUG_STKSZ > EXCEPTION_STKSZ - [N_EXCEPTION_STACKS ... N_EXCEPTION_STACKS + DEBUG_STKSZ / EXCEPTION_STKSZ - 2] = "#DB[?]" -#endif - }; - unsigned k; - - /* - * Iterate over all exception stacks, and figure out whether - * 'stack' is in one of them: - */ - for (k = 0; k < N_EXCEPTION_STACKS; k++) { - unsigned long end = per_cpu(orig_ist, cpu).ist[k]; - /* - * Is 'stack' above this exception frame's end? - * If yes then skip to the next frame. - */ - if (stack >= end) - continue; - /* - * Is 'stack' above this exception frame's start address? - * If yes then we found the right frame. - */ - if (stack >= end - EXCEPTION_STKSZ) { - /* - * Make sure we only iterate through an exception - * stack once. If it comes up for the second time - * then there's something wrong going on - just - * break out and return NULL: - */ - if (*usedp & (1U << k)) - break; - *usedp |= 1U << k; - *idp = ids[k]; - return (unsigned long *)end; - } - /* - * If this is a debug stack, and if it has a larger size than - * the usual exception stacks, then 'stack' might still - * be within the lower portion of the debug stack: - */ -#if DEBUG_STKSZ > EXCEPTION_STKSZ - if (k == DEBUG_STACK - 1 && stack >= end - DEBUG_STKSZ) { - unsigned j = N_EXCEPTION_STACKS - 1; - - /* - * Black magic. A large debug stack is composed of - * multiple exception stack entries, which we - * iterate through now. Dont look: - */ - do { - ++j; - end -= EXCEPTION_STKSZ; - ids[j][4] = '1' + (j - N_EXCEPTION_STACKS); - } while (stack < end - EXCEPTION_STKSZ); - if (*usedp & (1U << j)) - break; - *usedp |= 1U << j; - *idp = ids[j]; - return (unsigned long *)end; - } -#endif - } - return NULL; -} - -#define MSG(txt) ops->warning(data, txt) - -/* - * x86-64 can have upto three kernel stacks: - * process stack - * interrupt stack - * severe exception (double fault, nmi, stack fault, debug, mce) hardware stack - */ - -static inline int valid_stack_ptr(struct thread_info *tinfo, void *p) -{ - void *t = (void *)tinfo; - return p > t && p < t + THREAD_SIZE - 3; -} - -void dump_trace(struct task_struct *tsk, struct pt_regs *regs, - unsigned long *stack, - struct stacktrace_ops *ops, void *data) -{ - const unsigned cpu = get_cpu(); - unsigned long *irqstack_end = (unsigned long*)cpu_pda(cpu)->irqstackptr; - unsigned used = 0; - struct thread_info *tinfo; - - if (!tsk) - tsk = current; - - if (!stack) { - unsigned long dummy; - stack = &dummy; - if (tsk && tsk != current) - stack = (unsigned long *)tsk->thread.rsp; - } - - /* - * Print function call entries within a stack. 'cond' is the - * "end of stackframe" condition, that the 'stack++' - * iteration will eventually trigger. - */ -#define HANDLE_STACK(cond) \ - do while (cond) { \ - unsigned long addr = *stack++; \ - /* Use unlocked access here because except for NMIs \ - we should be already protected against module unloads */ \ - if (__kernel_text_address(addr)) { \ - /* \ - * If the address is either in the text segment of the \ - * kernel, or in the region which contains vmalloc'ed \ - * memory, it *may* be the address of a calling \ - * routine; if so, print it so that someone tracing \ - * down the cause of the crash will be able to figure \ - * out the call path that was taken. \ - */ \ - ops->address(data, addr); \ - } \ - } while (0) - - /* - * Print function call entries in all stacks, starting at the - * current stack address. If the stacks consist of nested - * exceptions - */ - for (;;) { - char *id; - unsigned long *estack_end; - estack_end = in_exception_stack(cpu, (unsigned long)stack, - &used, &id); - - if (estack_end) { - if (ops->stack(data, id) < 0) - break; - HANDLE_STACK (stack < estack_end); - ops->stack(data, "<EOE>"); - /* - * We link to the next stack via the - * second-to-last pointer (index -2 to end) in the - * exception stack: - */ - stack = (unsigned long *) estack_end[-2]; - continue; - } - if (irqstack_end) { - unsigned long *irqstack; - irqstack = irqstack_end - - (IRQSTACKSIZE - 64) / sizeof(*irqstack); - - if (stack >= irqstack && stack < irqstack_end) { - if (ops->stack(data, "IRQ") < 0) - break; - HANDLE_STACK (stack < irqstack_end); - /* - * We link to the next stack (which would be - * the process stack normally) the last - * pointer (index -1 to end) in the IRQ stack: - */ - stack = (unsigned long *) (irqstack_end[-1]); - irqstack_end = NULL; - ops->stack(data, "EOI"); - continue; - } - } - break; - } - - /* - * This handles the process stack: - */ - tinfo = task_thread_info(tsk); - HANDLE_STACK (valid_stack_ptr(tinfo, stack)); -#undef HANDLE_STACK - put_cpu(); -} -EXPORT_SYMBOL(dump_trace); - -static void -print_trace_warning_symbol(void *data, char *msg, unsigned long symbol) -{ - print_symbol(msg, symbol); - printk("\n"); -} - -static void print_trace_warning(void *data, char *msg) -{ - printk("%s\n", msg); -} - -static int print_trace_stack(void *data, char *name) -{ - printk(" <%s> ", name); - return 0; -} - -static void print_trace_address(void *data, unsigned long addr) -{ - touch_nmi_watchdog(); - printk_address(addr); -} - -static struct stacktrace_ops print_trace_ops = { - .warning = print_trace_warning, - .warning_symbol = print_trace_warning_symbol, - .stack = print_trace_stack, - .address = print_trace_address, -}; - -void -show_trace(struct task_struct *tsk, struct pt_regs *regs, unsigned long *stack) -{ - printk("\nCall Trace:\n"); - dump_trace(tsk, regs, stack, &print_trace_ops, NULL); - printk("\n"); -} - -static void -_show_stack(struct task_struct *tsk, struct pt_regs *regs, unsigned long *rsp) -{ - unsigned long *stack; - int i; - const int cpu = smp_processor_id(); - unsigned long *irqstack_end = (unsigned long *) (cpu_pda(cpu)->irqstackptr); - unsigned long *irqstack = (unsigned long *) (cpu_pda(cpu)->irqstackptr - IRQSTACKSIZE); - - // debugging aid: "show_stack(NULL, NULL);" prints the - // back trace for this cpu. - - if (rsp == NULL) { - if (tsk) - rsp = (unsigned long *)tsk->thread.rsp; - else - rsp = (unsigned long *)&rsp; - } - - stack = rsp; - for(i=0; i < kstack_depth_to_print; i++) { - if (stack >= irqstack && stack <= irqstack_end) { - if (stack == irqstack_end) { - stack = (unsigned long *) (irqstack_end[-1]); - printk(" <EOI> "); - } - } else { - if (((long) stack & (THREAD_SIZE-1)) == 0) - break; - } - if (i && ((i % 4) == 0)) - printk("\n"); - printk(" %016lx", *stack++); - touch_nmi_watchdog(); - } - show_trace(tsk, regs, rsp); -} - -void show_stack(struct task_struct *tsk, unsigned long * rsp) -{ - _show_stack(tsk, NULL, rsp); -} - -/* - * The architecture-independent dump_stack generator - */ -void dump_stack(void) -{ - unsigned long dummy; - show_trace(NULL, NULL, &dummy); -} - -EXPORT_SYMBOL(dump_stack); - -void show_registers(struct pt_regs *regs) -{ - int i; - int in_kernel = !user_mode(regs); - unsigned long rsp; - const int cpu = smp_processor_id(); - struct task_struct *cur = cpu_pda(cpu)->pcurrent; - - rsp = regs->rsp; - printk("CPU %d ", cpu); - __show_regs(regs); - printk("Process %s (pid: %d, threadinfo %p, task %p)\n", - cur->comm, cur->pid, task_thread_info(cur), cur); - - /* - * When in-kernel, we also print out the stack and code at the - * time of the fault.. - */ - if (in_kernel) { - printk("Stack: "); - _show_stack(NULL, regs, (unsigned long*)rsp); - - printk("\nCode: "); - if (regs->rip < PAGE_OFFSET) - goto bad; - - for (i=0; i<20; i++) { - unsigned char c; - if (__get_user(c, &((unsigned char*)regs->rip)[i])) { -bad: - printk(" Bad RIP value."); - break; - } - printk("%02x ", c); - } - } - printk("\n"); -} - -int is_valid_bugaddr(unsigned long rip) -{ - unsigned short ud2; - - if (__copy_from_user(&ud2, (const void __user *) rip, sizeof(ud2))) - return 0; - - return ud2 == 0x0b0f; -} - -#ifdef CONFIG_BUG -void out_of_line_bug(void) -{ - BUG(); -} -EXPORT_SYMBOL(out_of_line_bug); -#endif - -static DEFINE_SPINLOCK(die_lock); -static int die_owner = -1; -static unsigned int die_nest_count; - -unsigned __kprobes long oops_begin(void) -{ - int cpu; - unsigned long flags; - - oops_enter(); - - /* racy, but better than risking deadlock. */ - local_irq_save(flags); - cpu = smp_processor_id(); - if (!spin_trylock(&die_lock)) { - if (cpu == die_owner) - /* nested oops. should stop eventually */; - else - spin_lock(&die_lock); - } - die_nest_count++; - die_owner = cpu; - console_verbose(); - bust_spinlocks(1); - return flags; -} - -void __kprobes oops_end(unsigned long flags) -{ - die_owner = -1; - bust_spinlocks(0); - die_nest_count--; - if (die_nest_count) - /* We still own the lock */ - local_irq_restore(flags); - else - /* Nest count reaches zero, release the lock. */ - spin_unlock_irqrestore(&die_lock, flags); - if (panic_on_oops) - panic("Fatal exception"); - oops_exit(); -} - -void __kprobes __die(const char * str, struct pt_regs * regs, long err) -{ - static int die_counter; - printk(KERN_EMERG "%s: %04lx [%u] ", str, err & 0xffff,++die_counter); -#ifdef CONFIG_PREEMPT - printk("PREEMPT "); -#endif -#ifdef CONFIG_SMP - printk("SMP "); -#endif -#ifdef CONFIG_DEBUG_PAGEALLOC - printk("DEBUG_PAGEALLOC"); -#endif - printk("\n"); - notify_die(DIE_OOPS, str, regs, err, current->thread.trap_no, SIGSEGV); - show_registers(regs); - add_taint(TAINT_DIE); - /* Executive summary in case the oops scrolled away */ - printk(KERN_ALERT "RIP "); - printk_address(regs->rip); - printk(" RSP <%016lx>\n", regs->rsp); - if (kexec_should_crash(current)) - crash_kexec(regs); -} - -void die(const char * str, struct pt_regs * regs, long err) -{ - unsigned long flags = oops_begin(); - - if (!user_mode(regs)) - report_bug(regs->rip, regs); - - __die(str, regs, err); - oops_end(flags); - do_exit(SIGSEGV); -} - -void __kprobes die_nmi(char *str, struct pt_regs *regs, int do_panic) -{ - unsigned long flags = oops_begin(); - - /* - * We are in trouble anyway, lets at least try - * to get a message out. - */ - printk(str, smp_processor_id()); - show_registers(regs); - if (kexec_should_crash(current)) - crash_kexec(regs); - if (do_panic || panic_on_oops) - panic("Non maskable interrupt"); - oops_end(flags); - nmi_exit(); - local_irq_enable(); - do_exit(SIGSEGV); -} - -static void __kprobes do_trap(int trapnr, int signr, char *str, - struct pt_regs * regs, long error_code, - siginfo_t *info) -{ - struct task_struct *tsk = current; - - if (user_mode(regs)) { - /* - * We want error_code and trap_no set for userspace - * faults and kernelspace faults which result in - * die(), but not kernelspace faults which are fixed - * up. die() gives the process no chance to handle - * the signal and notice the kernel fault information, - * so that won't result in polluting the information - * about previously queued, but not yet delivered, - * faults. See also do_general_protection below. - */ - tsk->thread.error_code = error_code; - tsk->thread.trap_no = trapnr; - - if (show_unhandled_signals && unhandled_signal(tsk, signr) && - printk_ratelimit()) - printk(KERN_INFO - "%s[%d] trap %s rip:%lx rsp:%lx error:%lx\n", - tsk->comm, tsk->pid, str, - regs->rip, regs->rsp, error_code); - - if (info) - force_sig_info(signr, info, tsk); - else - force_sig(signr, tsk); - return; - } - - - /* kernel trap */ - { - const struct exception_table_entry *fixup; - fixup = search_exception_tables(regs->rip); - if (fixup) - regs->rip = fixup->fixup; - else { - tsk->thread.error_code = error_code; - tsk->thread.trap_no = trapnr; - die(str, regs, error_code); - } - return; - } -} - -#define DO_ERROR(trapnr, signr, str, name) \ -asmlinkage void do_##name(struct pt_regs * regs, long error_code) \ -{ \ - if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \ - == NOTIFY_STOP) \ - return; \ - conditional_sti(regs); \ - do_trap(trapnr, signr, str, regs, error_code, NULL); \ -} - -#define DO_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr) \ -asmlinkage 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; \ - conditional_sti(regs); \ - do_trap(trapnr, signr, str, regs, error_code, &info); \ -} - -DO_ERROR_INFO( 0, SIGFPE, "divide error", divide_error, FPE_INTDIV, regs->rip) -DO_ERROR( 4, SIGSEGV, "overflow", overflow) -DO_ERROR( 5, SIGSEGV, "bounds", bounds) -DO_ERROR_INFO( 6, SIGILL, "invalid opcode", invalid_op, ILL_ILLOPN, regs->rip) -DO_ERROR( 7, SIGSEGV, "device not available", device_not_available) -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_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, 0) -DO_ERROR(18, SIGSEGV, "reserved", reserved) - -/* Runs on IST stack */ -asmlinkage void do_stack_segment(struct pt_regs *regs, long error_code) -{ - if (notify_die(DIE_TRAP, "stack segment", regs, error_code, - 12, SIGBUS) == NOTIFY_STOP) - return; - preempt_conditional_sti(regs); - do_trap(12, SIGBUS, "stack segment", regs, error_code, NULL); - preempt_conditional_cli(regs); -} - -asmlinkage void do_double_fault(struct pt_regs * regs, long error_code) -{ - static const char str[] = "double fault"; - struct task_struct *tsk = current; - - /* Return not checked because double check cannot be ignored */ - notify_die(DIE_TRAP, str, regs, error_code, 8, SIGSEGV); - - tsk->thread.error_code = error_code; - tsk->thread.trap_no = 8; - - /* This is always a kernel trap and never fixable (and thus must - never return). */ - for (;;) - die(str, regs, error_code); -} - -asmlinkage void __kprobes do_general_protection(struct pt_regs * regs, - long error_code) -{ - struct task_struct *tsk = current; - - conditional_sti(regs); - - if (user_mode(regs)) { - tsk->thread.error_code = error_code; - tsk->thread.trap_no = 13; - - if (show_unhandled_signals && unhandled_signal(tsk, SIGSEGV) && - printk_ratelimit()) - printk(KERN_INFO - "%s[%d] general protection rip:%lx rsp:%lx error:%lx\n", - tsk->comm, tsk->pid, - regs->rip, regs->rsp, error_code); - - force_sig(SIGSEGV, tsk); - return; - } - - /* kernel gp */ - { - const struct exception_table_entry *fixup; - fixup = search_exception_tables(regs->rip); - if (fixup) { - regs->rip = fixup->fixup; - return; - } - - tsk->thread.error_code = error_code; - tsk->thread.trap_no = 13; - if (notify_die(DIE_GPF, "general protection fault", regs, - error_code, 13, SIGSEGV) == NOTIFY_STOP) - return; - die("general protection fault", regs, error_code); - } -} - -static __kprobes void -mem_parity_error(unsigned char reason, struct pt_regs * regs) -{ - printk(KERN_EMERG "Uhhuh. NMI received for unknown reason %02x.\n", - reason); - printk(KERN_EMERG "You have some hardware problem, likely on the PCI bus.\n"); - -#if defined(CONFIG_EDAC) - if(edac_handler_set()) { - edac_atomic_assert_error(); - return; - } -#endif - - if (panic_on_unrecovered_nmi) - panic("NMI: Not continuing"); - - printk(KERN_EMERG "Dazed and confused, but trying to continue\n"); - - /* Clear and disable the memory parity error line. */ - reason = (reason & 0xf) | 4; - outb(reason, 0x61); -} - -static __kprobes void -io_check_error(unsigned char reason, struct pt_regs * regs) -{ - 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); - mdelay(2000); - reason &= ~8; - outb(reason, 0x61); -} - -static __kprobes void -unknown_nmi_error(unsigned char reason, struct pt_regs * regs) -{ - printk(KERN_EMERG "Uhhuh. NMI received for unknown reason %02x.\n", - reason); - printk(KERN_EMERG "Do you have a strange power saving mode enabled?\n"); - - if (panic_on_unrecovered_nmi) - panic("NMI: Not continuing"); - - printk(KERN_EMERG "Dazed and confused, but trying to continue\n"); -} - -/* Runs on IST stack. This code must keep interrupts off all the time. - Nested NMIs are prevented by the CPU. */ -asmlinkage __kprobes void default_do_nmi(struct pt_regs *regs) -{ - unsigned char reason = 0; - int cpu; - - cpu = smp_processor_id(); - - /* Only the BSP gets external NMIs from the system. */ - if (!cpu) - reason = get_nmi_reason(); - - if (!(reason & 0xc0)) { - if (notify_die(DIE_NMI_IPI, "nmi_ipi", regs, reason, 2, SIGINT) - == NOTIFY_STOP) - return; - /* - * Ok, so this is none of the documented NMI sources, - * so it must be the NMI watchdog. - */ - if (nmi_watchdog_tick(regs,reason)) - return; - if (!do_nmi_callback(regs,cpu)) - unknown_nmi_error(reason, regs); - - return; - } - if (notify_die(DIE_NMI, "nmi", regs, reason, 2, SIGINT) == NOTIFY_STOP) - return; - - /* AK: following checks seem to be broken on modern chipsets. FIXME */ - - if (reason & 0x80) - mem_parity_error(reason, regs); - if (reason & 0x40) - io_check_error(reason, regs); -} - -/* runs on IST stack. */ -asmlinkage 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; - } - preempt_conditional_sti(regs); - do_trap(3, SIGTRAP, "int3", regs, error_code, NULL); - preempt_conditional_cli(regs); -} - -/* Help handler running on IST stack to switch back to user stack - for scheduling or signal handling. The actual stack switch is done in - entry.S */ -asmlinkage __kprobes struct pt_regs *sync_regs(struct pt_regs *eregs) -{ - struct pt_regs *regs = eregs; - /* Did already sync */ - if (eregs == (struct pt_regs *)eregs->rsp) - ; - /* Exception from user space */ - else if (user_mode(eregs)) - regs = task_pt_regs(current); - /* Exception from kernel and interrupts are enabled. Move to - kernel process stack. */ - else if (eregs->eflags & X86_EFLAGS_IF) - regs = (struct pt_regs *)(eregs->rsp -= sizeof(struct pt_regs)); - if (eregs != regs) - *regs = *eregs; - return regs; -} - -/* runs on IST stack. */ -asmlinkage void __kprobes do_debug(struct pt_regs * regs, - unsigned long error_code) -{ - unsigned long condition; - struct task_struct *tsk = current; - siginfo_t info; - - get_debugreg(condition, 6); - - if (notify_die(DIE_DEBUG, "debug", regs, condition, error_code, - SIGTRAP) == NOTIFY_STOP) - return; - - preempt_conditional_sti(regs); - - /* Mask out spurious debug traps due to lazy DR7 setting */ - if (condition & (DR_TRAP0|DR_TRAP1|DR_TRAP2|DR_TRAP3)) { - if (!tsk->thread.debugreg7) { - goto clear_dr7; - } - } - - tsk->thread.debugreg6 = condition; - - /* Mask out spurious TF errors due to lazy TF clearing */ - if (condition & DR_STEP) { - /* - * The TF error should be masked out only if the current - * process is not traced and if the TRAP flag has been set - * previously by a tracing process (condition detected by - * the PT_DTRACE flag); remember that the i386 TRAP flag - * can be modified by the process itself in user mode, - * allowing programs to debug themselves without the ptrace() - * interface. - */ - if (!user_mode(regs)) - goto clear_TF_reenable; - /* - * Was the TF flag set by a debugger? If so, clear it now, - * so that register information is correct. - */ - if (tsk->ptrace & PT_DTRACE) { - regs->eflags &= ~TF_MASK; - tsk->ptrace &= ~PT_DTRACE; - } - } - - /* Ok, finally something we can handle */ - tsk->thread.trap_no = 1; - tsk->thread.error_code = error_code; - info.si_signo = SIGTRAP; - info.si_errno = 0; - info.si_code = TRAP_BRKPT; - info.si_addr = user_mode(regs) ? (void __user *)regs->rip : NULL; - force_sig_info(SIGTRAP, &info, tsk); - -clear_dr7: - set_debugreg(0UL, 7); - preempt_conditional_cli(regs); - return; - -clear_TF_reenable: - set_tsk_thread_flag(tsk, TIF_SINGLESTEP); - regs->eflags &= ~TF_MASK; - preempt_conditional_cli(regs); -} - -static int kernel_math_error(struct pt_regs *regs, const char *str, int trapnr) -{ - const struct exception_table_entry *fixup; - fixup = search_exception_tables(regs->rip); - if (fixup) { - regs->rip = fixup->fixup; - return 1; - } - notify_die(DIE_GPF, str, regs, 0, trapnr, SIGFPE); - /* Illegal floating point operation in the kernel */ - current->thread.trap_no = trapnr; - die(str, regs, 0); - return 0; -} - -/* - * 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 - */ -asmlinkage void do_coprocessor_error(struct pt_regs *regs) -{ - void __user *rip = (void __user *)(regs->rip); - struct task_struct * task; - siginfo_t info; - unsigned short cwd, swd; - - conditional_sti(regs); - if (!user_mode(regs) && - kernel_math_error(regs, "kernel x87 math error", 16)) - return; - - /* - * 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 = rip; - /* - * (~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 synchronizing 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: - default: - 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); -} - -asmlinkage void bad_intr(void) -{ - printk("bad interrupt"); -} - -asmlinkage void do_simd_coprocessor_error(struct pt_regs *regs) -{ - void __user *rip = (void __user *)(regs->rip); - struct task_struct * task; - siginfo_t info; - unsigned short mxcsr; - - conditional_sti(regs); - if (!user_mode(regs) && - kernel_math_error(regs, "kernel simd math error", 19)) - return; - - /* - * 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 = rip; - /* - * 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); -} - -asmlinkage void do_spurious_interrupt_bug(struct pt_regs * regs) -{ -} - -asmlinkage void __attribute__((weak)) smp_thermal_interrupt(void) -{ -} - -asmlinkage void __attribute__((weak)) mce_threshold_interrupt(void) -{ -} - -/* - * '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. - */ -asmlinkage void math_state_restore(void) -{ - struct task_struct *me = current; - clts(); /* Allow maths ops (or we recurse) */ - - if (!used_math()) - init_fpu(me); - restore_fpu_checking(&me->thread.i387.fxsave); - task_thread_info(me)->status |= TS_USEDFPU; - me->fpu_counter++; -} - -void __init trap_init(void) -{ - set_intr_gate(0,÷_error); - set_intr_gate_ist(1,&debug,DEBUG_STACK); - set_intr_gate_ist(2,&nmi,NMI_STACK); - set_system_gate_ist(3,&int3,DEBUG_STACK); /* int3 can be called from all */ - set_system_gate(4,&overflow); /* int4 can be called from all */ - set_intr_gate(5,&bounds); - set_intr_gate(6,&invalid_op); - set_intr_gate(7,&device_not_available); - set_intr_gate_ist(8,&double_fault, DOUBLEFAULT_STACK); - set_intr_gate(9,&coprocessor_segment_overrun); - set_intr_gate(10,&invalid_TSS); - set_intr_gate(11,&segment_not_present); - set_intr_gate_ist(12,&stack_segment,STACKFAULT_STACK); - set_intr_gate(13,&general_protection); - set_intr_gate(14,&page_fault); - set_intr_gate(15,&spurious_interrupt_bug); - set_intr_gate(16,&coprocessor_error); - set_intr_gate(17,&alignment_check); -#ifdef CONFIG_X86_MCE - set_intr_gate_ist(18,&machine_check, MCE_STACK); -#endif - set_intr_gate(19,&simd_coprocessor_error); - -#ifdef CONFIG_IA32_EMULATION - set_system_gate(IA32_SYSCALL_VECTOR, ia32_syscall); -#endif - - /* - * Should be a barrier for any external CPU state. - */ - cpu_init(); -} - - -static int __init oops_setup(char *s) -{ - if (!s) - return -EINVAL; - if (!strcmp(s, "panic")) - panic_on_oops = 1; - return 0; -} -early_param("oops", oops_setup); - -static int __init kstack_setup(char *s) -{ - if (!s) - return -EINVAL; - kstack_depth_to_print = simple_strtoul(s,NULL,0); - return 0; -} -early_param("kstack", kstack_setup); |