1220 lines
30 KiB
C
1220 lines
30 KiB
C
/*
|
|
* 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 <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/kdebug.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);
|
|
|
|
ATOMIC_NOTIFIER_HEAD(die_chain);
|
|
EXPORT_SYMBOL(die_chain);
|
|
|
|
int register_die_notifier(struct notifier_block *nb)
|
|
{
|
|
vmalloc_sync_all();
|
|
return atomic_notifier_chain_register(&die_chain, nb);
|
|
}
|
|
EXPORT_SYMBOL(register_die_notifier); /* used modular by kdb */
|
|
|
|
int unregister_die_notifier(struct notifier_block *nb)
|
|
{
|
|
return atomic_notifier_chain_unregister(&die_chain, nb);
|
|
}
|
|
EXPORT_SYMBOL(unregister_die_notifier); /* used modular by kdb */
|
|
|
|
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();
|
|
}
|
|
|
|
static int kstack_depth_to_print = 12;
|
|
#ifdef CONFIG_STACK_UNWIND
|
|
static int call_trace = 1;
|
|
#else
|
|
#define call_trace (-1)
|
|
#endif
|
|
|
|
#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;
|
|
}
|
|
|
|
struct ops_and_data {
|
|
struct stacktrace_ops *ops;
|
|
void *data;
|
|
};
|
|
|
|
static int dump_trace_unwind(struct unwind_frame_info *info, void *context)
|
|
{
|
|
struct ops_and_data *oad = (struct ops_and_data *)context;
|
|
int n = 0;
|
|
|
|
while (unwind(info) == 0 && UNW_PC(info)) {
|
|
n++;
|
|
oad->ops->address(oad->data, UNW_PC(info));
|
|
if (arch_unw_user_mode(info))
|
|
break;
|
|
}
|
|
return n;
|
|
}
|
|
|
|
#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 (call_trace >= 0) {
|
|
int unw_ret = 0;
|
|
struct unwind_frame_info info;
|
|
struct ops_and_data oad = { .ops = ops, .data = data };
|
|
|
|
if (regs) {
|
|
if (unwind_init_frame_info(&info, tsk, regs) == 0)
|
|
unw_ret = dump_trace_unwind(&info, &oad);
|
|
} else if (tsk == current)
|
|
unw_ret = unwind_init_running(&info, dump_trace_unwind,
|
|
&oad);
|
|
else {
|
|
if (unwind_init_blocked(&info, tsk) == 0)
|
|
unw_ret = dump_trace_unwind(&info, &oad);
|
|
}
|
|
if (unw_ret > 0) {
|
|
if (call_trace == 1 && !arch_unw_user_mode(&info)) {
|
|
ops->warning_symbol(data,
|
|
"DWARF2 unwinder stuck at %s",
|
|
UNW_PC(&info));
|
|
if ((long)UNW_SP(&info) < 0) {
|
|
MSG("Leftover inexact backtrace:");
|
|
stack = (unsigned long *)UNW_SP(&info);
|
|
if (!stack)
|
|
goto out;
|
|
} else
|
|
MSG("Full inexact backtrace again:");
|
|
} else if (call_trace >= 1)
|
|
goto out;
|
|
else
|
|
MSG("Full inexact backtrace again:");
|
|
} else
|
|
MSG("Inexact backtrace:");
|
|
}
|
|
if (!stack) {
|
|
unsigned long dummy;
|
|
stack = &dummy;
|
|
if (tsk && tsk != current)
|
|
stack = (unsigned long *)tsk->thread.rsp;
|
|
}
|
|
/*
|
|
* Align the stack pointer on word boundary, later loops
|
|
* rely on that (and corruption / debug info bugs can cause
|
|
* unaligned values here):
|
|
*/
|
|
stack = (unsigned long *)((unsigned long)stack & ~(sizeof(long)-1));
|
|
|
|
/*
|
|
* 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++; \
|
|
if (oops_in_progress ? \
|
|
__kernel_text_address(addr) : \
|
|
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 = current_thread_info();
|
|
HANDLE_STACK (valid_stack_ptr(tinfo, stack));
|
|
#undef HANDLE_STACK
|
|
out:
|
|
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)
|
|
{
|
|
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");
|
|
}
|
|
|
|
void handle_BUG(struct pt_regs *regs)
|
|
{
|
|
struct bug_frame f;
|
|
long len;
|
|
const char *prefix = "";
|
|
|
|
if (user_mode(regs))
|
|
return;
|
|
if (__copy_from_user(&f, (const void __user *) regs->rip,
|
|
sizeof(struct bug_frame)))
|
|
return;
|
|
if (f.filename >= 0 ||
|
|
f.ud2[0] != 0x0f || f.ud2[1] != 0x0b)
|
|
return;
|
|
len = __strnlen_user((char *)(long)f.filename, PATH_MAX) - 1;
|
|
if (len < 0 || len >= PATH_MAX)
|
|
f.filename = (int)(long)"unmapped filename";
|
|
else if (len > 50) {
|
|
f.filename += len - 50;
|
|
prefix = "...";
|
|
}
|
|
printk("----------- [cut here ] --------- [please bite here ] ---------\n");
|
|
printk(KERN_ALERT "Kernel BUG at %s%.50s:%d\n", prefix, (char *)(long)f.filename, f.line);
|
|
}
|
|
|
|
#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 = smp_processor_id();
|
|
unsigned long flags;
|
|
|
|
oops_enter();
|
|
|
|
/* racy, but better than risking deadlock. */
|
|
local_irq_save(flags);
|
|
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);
|
|
/* 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();
|
|
|
|
handle_BUG(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;
|
|
|
|
tsk->thread.error_code = error_code;
|
|
tsk->thread.trap_no = trapnr;
|
|
|
|
if (user_mode(regs)) {
|
|
if (exception_trace && unhandled_signal(tsk, signr))
|
|
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
|
|
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);
|
|
|
|
tsk->thread.error_code = error_code;
|
|
tsk->thread.trap_no = 13;
|
|
|
|
if (user_mode(regs)) {
|
|
if (exception_trace && unhandled_signal(tsk, SIGSEGV))
|
|
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;
|
|
}
|
|
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 (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);
|
|
|
|
#ifdef CONFIG_STACK_UNWIND
|
|
static int __init call_trace_setup(char *s)
|
|
{
|
|
if (!s)
|
|
return -EINVAL;
|
|
if (strcmp(s, "old") == 0)
|
|
call_trace = -1;
|
|
else if (strcmp(s, "both") == 0)
|
|
call_trace = 0;
|
|
else if (strcmp(s, "newfallback") == 0)
|
|
call_trace = 1;
|
|
else if (strcmp(s, "new") == 0)
|
|
call_trace = 2;
|
|
return 0;
|
|
}
|
|
early_param("call_trace", call_trace_setup);
|
|
#endif
|