Merge branch 'x86/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip...
[linux-2.6.git] / arch / x86 / kernel / traps_64.c
index f1a95d1..2696a68 100644 (file)
  * 'Traps.c' handles hardware traps and faults after we have saved some
  * state in 'entry.S'.
  */
-#include <linux/sched.h>
+#include <linux/moduleparam.h>
+#include <linux/interrupt.h>
+#include <linux/kallsyms.h>
+#include <linux/spinlock.h>
+#include <linux/kprobes.h>
+#include <linux/uaccess.h>
+#include <linux/utsname.h>
+#include <linux/kdebug.h>
 #include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/ptrace.h>
 #include <linux/string.h>
+#include <linux/unwind.h>
+#include <linux/delay.h>
 #include <linux/errno.h>
-#include <linux/ptrace.h>
+#include <linux/kexec.h>
+#include <linux/sched.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>
-#include <linux/utsname.h>
-
-#include <mach_traps.h>
+#include <linux/nmi.h>
+#include <linux/mm.h>
 
 #if defined(CONFIG_EDAC)
 #include <linux/edac.h>
 #endif
 
-#include <asm/system.h>
-#include <asm/io.h>
-#include <asm/atomic.h>
+#include <asm/stacktrace.h>
+#include <asm/processor.h>
 #include <asm/debugreg.h>
+#include <asm/atomic.h>
+#include <asm/system.h>
+#include <asm/unwind.h>
 #include <asm/desc.h>
 #include <asm/i387.h>
-#include <asm/processor.h>
-#include <asm/unwind.h>
+#include <asm/nmi.h>
 #include <asm/smp.h>
+#include <asm/io.h>
 #include <asm/pgalloc.h>
-#include <asm/pda.h>
 #include <asm/proto.h>
-#include <asm/nmi.h>
-#include <asm/stacktrace.h>
+#include <asm/pda.h>
+
+#include <mach_traps.h>
 
 asmlinkage void divide_error(void);
 asmlinkage void debug(void);
@@ -71,12 +71,15 @@ 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);
+asmlinkage void machine_check(void);
 
+int panic_on_unrecovered_nmi;
+int kstack_depth_to_print = 12;
 static unsigned int code_bytes = 64;
+static int ignore_nmis;
+static int die_counter;
 
 static inline void conditional_sti(struct pt_regs *regs)
 {
@@ -100,8 +103,6 @@ static inline void preempt_conditional_cli(struct pt_regs *regs)
        dec_preempt_count();
 }
 
-int kstack_depth_to_print = 12;
-
 void printk_address(unsigned long address, int reliable)
 {
        printk(" [<%016lx>] %s%pS\n", address, reliable ? "": "? ", (void *) address);
@@ -181,8 +182,6 @@ static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack,
        return NULL;
 }
 
-#define MSG(txt) ops->warning(data, txt)
-
 /*
  * x86-64 can have up to three kernel stacks: 
  * process stack
@@ -209,11 +208,11 @@ struct stack_frame {
        unsigned long return_address;
 };
 
-
-static inline unsigned long print_context_stack(struct thread_info *tinfo,
-                               unsigned long *stack, unsigned long bp,
-                               const struct stacktrace_ops *ops, void *data,
-                               unsigned long *end)
+static inline unsigned long
+print_context_stack(struct thread_info *tinfo,
+               unsigned long *stack, unsigned long bp,
+               const struct stacktrace_ops *ops, void *data,
+               unsigned long *end)
 {
        struct stack_frame *frame = (struct stack_frame *)bp;
 
@@ -235,7 +234,7 @@ static inline unsigned long print_context_stack(struct thread_info *tinfo,
        return bp;
 }
 
-void dump_trace(struct task_struct *tsk, struct pt_regs *regs,
+void dump_trace(struct task_struct *task, struct pt_regs *regs,
                unsigned long *stack, unsigned long bp,
                const struct stacktrace_ops *ops, void *data)
 {
@@ -244,36 +243,34 @@ void dump_trace(struct task_struct *tsk, struct pt_regs *regs,
        unsigned used = 0;
        struct thread_info *tinfo;
 
-       if (!tsk)
-               tsk = current;
-       tinfo = task_thread_info(tsk);
+       if (!task)
+               task = current;
 
        if (!stack) {
                unsigned long dummy;
                stack = &dummy;
-               if (tsk && tsk != current)
-                       stack = (unsigned long *)tsk->thread.sp;
+               if (task && task != current)
+                       stack = (unsigned long *)task->thread.sp;
        }
 
 #ifdef CONFIG_FRAME_POINTER
        if (!bp) {
-               if (tsk == current) {
+               if (task == current) {
                        /* Grab bp right from our regs */
-                       asm("movq %%rbp, %0" : "=r" (bp):);
+                       asm("movq %%rbp, %0" : "=r" (bp) :);
                } else {
                        /* bp is the last reg pushed by switch_to */
-                       bp = *(unsigned long *) tsk->thread.sp;
+                       bp = *(unsigned long *) task->thread.sp;
                }
        }
 #endif
 
-
-
        /*
         * Print function call entries in all stacks, starting at the
         * current stack address. If the stacks consist of nested
         * exceptions
         */
+       tinfo = task_thread_info(task);
        for (;;) {
                char *id;
                unsigned long *estack_end;
@@ -358,18 +355,17 @@ static const struct stacktrace_ops print_trace_ops = {
        .address = print_trace_address,
 };
 
-void
-show_trace(struct task_struct *tsk, struct pt_regs *regs, unsigned long *stack,
-               unsigned long bp)
+void show_trace(struct task_struct *task, struct pt_regs *regs,
+               unsigned long *stack, unsigned long bp)
 {
        printk("\nCall Trace:\n");
-       dump_trace(tsk, regs, stack, bp, &print_trace_ops, NULL);
+       dump_trace(task, regs, stack, bp, &print_trace_ops, NULL);
        printk("\n");
 }
 
 static void
-_show_stack(struct task_struct *tsk, struct pt_regs *regs, unsigned long *sp,
-                                                       unsigned long bp)
+_show_stack(struct task_struct *task, struct pt_regs *regs,
+               unsigned long *sp, unsigned long bp)
 {
        unsigned long *stack;
        int i;
@@ -381,14 +377,14 @@ _show_stack(struct task_struct *tsk, struct pt_regs *regs, unsigned long *sp,
        // back trace for this cpu.
 
        if (sp == NULL) {
-               if (tsk)
-                       sp = (unsigned long *)tsk->thread.sp;
+               if (task)
+                       sp = (unsigned long *)task->thread.sp;
                else
                        sp = (unsigned long *)&sp;
        }
 
        stack = sp;
-       for(i=0; i < kstack_depth_to_print; i++) {
+       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]);
@@ -403,12 +399,12 @@ _show_stack(struct task_struct *tsk, struct pt_regs *regs, unsigned long *sp,
                printk(" %016lx", *stack++);
                touch_nmi_watchdog();
        }
-       show_trace(tsk, regs, sp, bp);
+       show_trace(task, regs, sp, bp);
 }
 
-void show_stack(struct task_struct *tsk, unsigned long * sp)
+void show_stack(struct task_struct *task, unsigned long *sp)
 {
-       _show_stack(tsk, NULL, sp, 0);
+       _show_stack(task, NULL, sp, 0);
 }
 
 /*
@@ -416,8 +412,8 @@ void show_stack(struct task_struct *tsk, unsigned long * sp)
  */
 void dump_stack(void)
 {
-       unsigned long dummy;
        unsigned long bp = 0;
+       unsigned long stack;
 
 #ifdef CONFIG_FRAME_POINTER
        if (!bp)
@@ -429,7 +425,7 @@ void dump_stack(void)
                init_utsname()->release,
                (int)strcspn(init_utsname()->version, " "),
                init_utsname()->version);
-       show_trace(NULL, NULL, &dummy, bp);
+       show_trace(NULL, NULL, &stack, bp);
 }
 
 EXPORT_SYMBOL(dump_stack);
@@ -440,12 +436,8 @@ void show_registers(struct pt_regs *regs)
        unsigned long sp;
        const int cpu = smp_processor_id();
        struct task_struct *cur = cpu_pda(cpu)->pcurrent;
-       u8 *ip;
-       unsigned int code_prologue = code_bytes * 43 / 64;
-       unsigned int code_len = code_bytes;
 
        sp = regs->sp;
-       ip = (u8 *) regs->ip - code_prologue;
        printk("CPU %d ", cpu);
        __show_regs(regs);
        printk("Process %s (pid: %d, threadinfo %p, task %p)\n",
@@ -456,15 +448,21 @@ void show_registers(struct pt_regs *regs)
         * time of the fault..
         */
        if (!user_mode(regs)) {
+               unsigned int code_prologue = code_bytes * 43 / 64;
+               unsigned int code_len = code_bytes;
                unsigned char c;
+               u8 *ip;
+
                printk("Stack: ");
                _show_stack(NULL, regs, (unsigned long *)sp, regs->bp);
                printk("\n");
 
                printk(KERN_EMERG "Code: ");
+
+               ip = (u8 *)regs->ip - code_prologue;
                if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {
                        /* try starting at RIP */
-                       ip = (u8 *) regs->ip;
+                       ip = (u8 *)regs->ip;
                        code_len = code_len - code_prologue + 1;
                }
                for (i = 0; i < code_len; i++, ip++) {
@@ -480,7 +478,7 @@ void show_registers(struct pt_regs *regs)
                }
        }
        printk("\n");
-}      
+}
 
 int is_valid_bugaddr(unsigned long ip)
 {
@@ -538,10 +536,9 @@ void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr)
        do_exit(signr);
 }
 
-int __kprobes __die(const char * str, struct pt_regs * regs, long err)
+int __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);
+       printk(KERN_EMERG "%s: %04lx [%u] ", str, err & 0xffff, ++die_counter);
 #ifdef CONFIG_PREEMPT
        printk("PREEMPT ");
 #endif
@@ -552,8 +549,10 @@ int __kprobes __die(const char * str, struct pt_regs * regs, long err)
        printk("DEBUG_PAGEALLOC");
 #endif
        printk("\n");
-       if (notify_die(DIE_OOPS, str, regs, err, current->thread.trap_no, SIGSEGV) == NOTIFY_STOP)
+       if (notify_die(DIE_OOPS, str, regs, err,
+                       current->thread.trap_no, SIGSEGV) == NOTIFY_STOP)
                return 1;
+
        show_registers(regs);
        add_taint(TAINT_DIE);
        /* Executive summary in case the oops scrolled away */
@@ -565,7 +564,7 @@ int __kprobes __die(const char * str, struct pt_regs * regs, long err)
        return 0;
 }
 
-void die(const char * str, struct pt_regs * regs, long err)
+void die(const char *str, struct pt_regs *regs, long err)
 {
        unsigned long flags = oops_begin();
 
@@ -582,8 +581,7 @@ die_nmi(char *str, struct pt_regs *regs, int do_panic)
 {
        unsigned long flags;
 
-       if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, 2, SIGINT) ==
-           NOTIFY_STOP)
+       if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, 2, SIGINT) == NOTIFY_STOP)
                return;
 
        flags = oops_begin();
@@ -591,7 +589,9 @@ die_nmi(char *str, struct pt_regs *regs, int do_panic)
         * We are in trouble anyway, lets at least try
         * to get a message out.
         */
-       printk(str, smp_processor_id());
+       printk(KERN_EMERG "%s", str);
+       printk(" on CPU%d, ip %08lx, registers:\n",
+               smp_processor_id(), regs->ip);
        show_registers(regs);
        if (kexec_should_crash(current))
                crash_kexec(regs);
@@ -603,44 +603,44 @@ die_nmi(char *str, struct pt_regs *regs, int do_panic)
        do_exit(SIGBUS);
 }
 
-static void __kprobes do_trap(int trapnr, int signr, char *str,
-                             struct pt_regs * regs, long error_code,
-                             siginfo_t *info)
+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 ip:%lx sp:%lx error:%lx",
-                              tsk->comm, tsk->pid, str,
-                              regs->ip, regs->sp, error_code);
-                       print_vma_addr(" in ", regs->ip);
-                       printk("\n");
-               }
+       if (!user_mode(regs))
+               goto kernel_trap;
 
-               if (info)
-                       force_sig_info(signr, info, tsk);
-               else
-                       force_sig(signr, tsk);
-               return;
+       /*
+        * 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 ip:%lx sp:%lx error:%lx",
+                      tsk->comm, tsk->pid, str,
+                      regs->ip, regs->sp, error_code);
+               print_vma_addr(" in ", regs->ip);
+               printk("\n");
        }
 
+       if (info)
+               force_sig_info(signr, info, tsk);
+       else
+               force_sig(signr, tsk);
+       return;
 
+kernel_trap:
        if (!fixup_exception(regs)) {
                tsk->thread.error_code = error_code;
                tsk->thread.trap_no = trapnr;
@@ -650,41 +650,39 @@ static void __kprobes do_trap(int trapnr, int signr, char *str,
 }
 
 #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; \
+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); \
+       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; \
-       trace_hardirqs_fixup(); \
-       if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
-                                                       == NOTIFY_STOP) \
-               return; \
+#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;                           \
+       trace_hardirqs_fixup();                                         \
+       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_trap(trapnr, signr, str, regs, error_code, &info);           \
 }
 
-DO_ERROR_INFO( 0, SIGFPE,  "divide error", divide_error, FPE_INTDIV, regs->ip)
-DO_ERROR( 4, SIGSEGV, "overflow", overflow)
-DO_ERROR( 5, SIGSEGV, "bounds", bounds)
-DO_ERROR_INFO( 6, SIGILL,  "invalid opcode", invalid_op, ILL_ILLOPN, regs->ip)
-DO_ERROR( 7, SIGSEGV, "device not available", device_not_available)
-DO_ERROR( 9, SIGFPE,  "coprocessor segment overrun", coprocessor_segment_overrun)
+DO_ERROR_INFO(0, SIGFPE, "divide error", divide_error, FPE_INTDIV, regs->ip)
+DO_ERROR(4, SIGSEGV, "overflow", overflow)
+DO_ERROR(5, SIGSEGV, "bounds", bounds)
+DO_ERROR_INFO(6, SIGILL, "invalid opcode", invalid_op, ILL_ILLOPN, regs->ip)
+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(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)
@@ -714,31 +712,34 @@ asmlinkage void do_double_fault(struct pt_regs * regs, long error_code)
                die(str, regs, error_code);
 }
 
-asmlinkage void __kprobes do_general_protection(struct pt_regs * regs,
-                                               long error_code)
+asmlinkage void __kprobes
+do_general_protection(struct pt_regs *regs, long error_code)
 {
-       struct task_struct *tsk = current;
+       struct task_struct *tsk;
 
        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 ip:%lx sp:%lx error:%lx",
-                              tsk->comm, tsk->pid,
-                              regs->ip, regs->sp, error_code);
-                       print_vma_addr(" in ", regs->ip);
-                       printk("\n");
-               }
+       tsk = current;
+       if (!user_mode(regs))
+               goto gp_in_kernel;
 
-               force_sig(SIGSEGV, tsk);
-               return;
-       } 
+       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 ip:%lx sp:%lx error:%lx",
+                       tsk->comm, tsk->pid,
+                       regs->ip, regs->sp, error_code);
+               print_vma_addr(" in ", regs->ip);
+               printk("\n");
+       }
+
+       force_sig(SIGSEGV, tsk);
+       return;
 
+gp_in_kernel:
        if (fixup_exception(regs))
                return;
 
@@ -751,14 +752,14 @@ asmlinkage void __kprobes do_general_protection(struct pt_regs * regs,
 }
 
 static notrace __kprobes void
-mem_parity_error(unsigned char reason, struct pt_regs * regs)
+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()) {
+       if (edac_handler_set()) {
                edac_atomic_assert_error();
                return;
        }
@@ -775,7 +776,7 @@ mem_parity_error(unsigned char reason, struct pt_regs * regs)
 }
 
 static notrace __kprobes void
-io_check_error(unsigned char reason, struct pt_regs * regs)
+io_check_error(unsigned char reason, struct pt_regs *regs)
 {
        printk("NMI: IOCK error (debug interrupt?)\n");
        show_registers(regs);
@@ -805,14 +806,14 @@ unknown_nmi_error(unsigned char reason, struct pt_regs * regs)
 
 /* Runs on IST stack. This code must keep interrupts off all the time.
    Nested NMIs are prevented by the CPU. */
-asmlinkage notrace  __kprobes void default_do_nmi(struct pt_regs *regs)
+asmlinkage notrace __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.  */
+       /* Only the BSP gets external NMIs from the system. */
        if (!cpu)
                reason = get_nmi_reason();
 
@@ -824,32 +825,57 @@ asmlinkage notrace  __kprobes void default_do_nmi(struct pt_regs *regs)
                 * Ok, so this is none of the documented NMI sources,
                 * so it must be the NMI watchdog.
                 */
-               if (nmi_watchdog_tick(regs,reason))
+               if (nmi_watchdog_tick(regs, reason))
                        return;
-               if (!do_nmi_callback(regs,cpu))
+               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; 
+               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);
 }
 
+asmlinkage notrace __kprobes void
+do_nmi(struct pt_regs *regs, long error_code)
+{
+       nmi_enter();
+
+       add_pda(__nmi_count, 1);
+
+       if (!ignore_nmis)
+               default_do_nmi(regs);
+
+       nmi_exit();
+}
+
+void stop_nmi(void)
+{
+       acpi_nmi_disable();
+       ignore_nmis++;
+}
+
+void restart_nmi(void)
+{
+       ignore_nmis--;
+       acpi_nmi_enable();
+}
+
 /* runs on IST stack. */
-asmlinkage void __kprobes do_int3(struct pt_regs * regs, long error_code)
+asmlinkage void __kprobes do_int3(struct pt_regs *regs, long error_code)
 {
        trace_hardirqs_fixup();
 
-       if (notify_die(DIE_INT3, "int3", regs, error_code, 3, SIGTRAP) == NOTIFY_STOP) {
+       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);
@@ -880,8 +906,8 @@ asmlinkage __kprobes struct pt_regs *sync_regs(struct pt_regs *eregs)
 asmlinkage void __kprobes do_debug(struct pt_regs * regs,
                                   unsigned long error_code)
 {
-       unsigned long condition;
        struct task_struct *tsk = current;
+       unsigned long condition;
        siginfo_t info;
 
        trace_hardirqs_fixup();
@@ -902,21 +928,19 @@ asmlinkage void __kprobes do_debug(struct pt_regs * 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) { 
+               if (!tsk->thread.debugreg7)
                        goto clear_dr7;
-               }
        }
 
        tsk->thread.debugreg6 = 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) {
-                if (!user_mode(regs))
-                       goto clear_TF_reenable;
+               if (!user_mode(regs))
+                       goto clear_TF_reenable;
        }
 
        /* Ok, finally something we can handle */
@@ -929,7 +953,7 @@ asmlinkage void __kprobes do_debug(struct pt_regs * regs,
        force_sig_info(SIGTRAP, &info, tsk);
 
 clear_dr7:
-       set_debugreg(0UL, 7);
+       set_debugreg(0, 7);
        preempt_conditional_cli(regs);
        return;
 
@@ -937,6 +961,7 @@ clear_TF_reenable:
        set_tsk_thread_flag(tsk, TIF_SINGLESTEP);
        regs->flags &= ~X86_EFLAGS_TF;
        preempt_conditional_cli(regs);
+       return;
 }
 
 static int kernel_math_error(struct pt_regs *regs, const char *str, int trapnr)
@@ -959,7 +984,7 @@ static int kernel_math_error(struct pt_regs *regs, const char *str, int trapnr)
 asmlinkage void do_coprocessor_error(struct pt_regs *regs)
 {
        void __user *ip = (void __user *)(regs->ip);
-       struct task_struct * task;
+       struct task_struct *task;
        siginfo_t info;
        unsigned short cwd, swd;
 
@@ -992,30 +1017,30 @@ asmlinkage void do_coprocessor_error(struct pt_regs *regs)
        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;
+       case 0x000: /* No unmasked exception */
+       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);
 }
@@ -1028,7 +1053,7 @@ asmlinkage void bad_intr(void)
 asmlinkage void do_simd_coprocessor_error(struct pt_regs *regs)
 {
        void __user *ip = (void __user *)(regs->ip);
-       struct task_struct * task;
+       struct task_struct *task;
        siginfo_t info;
        unsigned short mxcsr;
 
@@ -1056,25 +1081,25 @@ asmlinkage void do_simd_coprocessor_error(struct pt_regs *regs)
         */
        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;
+       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);
 }
@@ -1092,7 +1117,7 @@ asmlinkage void __attribute__((weak)) mce_threshold_interrupt(void)
 }
 
 /*
- *  'math_state_restore()' saves the current math information in the
+ * '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.
@@ -1117,7 +1142,7 @@ asmlinkage void math_state_restore(void)
                local_irq_disable();
        }
 
-       clts();                 /* Allow maths ops (or we recurse) */
+       clts();                         /* Allow maths ops (or we recurse) */
        restore_fpu_checking(&me->thread.xstate->fxsave);
        task_thread_info(me)->status |= TS_USEDFPU;
        me->fpu_counter++;
@@ -1126,64 +1151,61 @@ EXPORT_SYMBOL_GPL(math_state_restore);
 
 void __init trap_init(void)
 {
-       set_intr_gate(0,&divide_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);
+       set_intr_gate(0, &divide_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); 
+       set_intr_gate_ist(18, &machine_check, MCE_STACK);
 #endif
-       set_intr_gate(19,&simd_coprocessor_error);
+       set_intr_gate(19, &simd_coprocessor_error);
 
 #ifdef CONFIG_IA32_EMULATION
        set_system_gate(IA32_SYSCALL_VECTOR, ia32_syscall);
 #endif
-       
        /*
         * initialize the per thread extended state:
         */
-        init_thread_xstate();
+       init_thread_xstate();
        /*
-        * Should be a barrier for any external CPU state.
+        * 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);
+       kstack_depth_to_print = simple_strtoul(s, NULL, 0);
        return 0;
 }
 early_param("kstack", kstack_setup);
 
-
 static int __init code_bytes_setup(char *s)
 {
        code_bytes = simple_strtoul(s, NULL, 0);