Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee13...
[pandora-kernel.git] / arch / i386 / kernel / traps.c
index 0d4005d..6820b8d 100644 (file)
@@ -28,6 +28,7 @@
 #include <linux/kprobes.h>
 #include <linux/kexec.h>
 #include <linux/unwind.h>
+#include <linux/uaccess.h>
 
 #ifdef CONFIG_EISA
 #include <linux/ioport.h>
@@ -40,7 +41,6 @@
 
 #include <asm/processor.h>
 #include <asm/system.h>
-#include <asm/uaccess.h>
 #include <asm/io.h>
 #include <asm/atomic.h>
 #include <asm/debugreg.h>
 #include <asm/smp.h>
 #include <asm/arch_hooks.h>
 #include <asm/kdebug.h>
+#include <asm/stacktrace.h>
 
 #include <linux/module.h>
 
 #include "mach_traps.h"
 
+int panic_on_unrecovered_nmi;
+
 asmlinkage int system_call(void);
 
 struct desc_struct default_ldt[] = { { 0, 0 }, { 0, 0 }, { 0, 0 },
@@ -92,7 +95,11 @@ asmlinkage void spurious_interrupt_bug(void);
 asmlinkage void machine_check(void);
 
 static int kstack_depth_to_print = 24;
+#ifdef CONFIG_STACK_UNWIND
 static int call_trace = 1;
+#else
+#define call_trace (-1)
+#endif
 ATOMIC_NOTIFIER_HEAD(i386die_chain);
 
 int register_die_notifier(struct notifier_block *nb)
@@ -114,26 +121,16 @@ static inline int valid_stack_ptr(struct thread_info *tinfo, void *p)
                p < (void *)tinfo + THREAD_SIZE - 3;
 }
 
-/*
- * Print one address/symbol entries per line.
- */
-static inline void print_addr_and_symbol(unsigned long addr, char *log_lvl)
-{
-       printk(" [<%08lx>] ", addr);
-
-       print_symbol("%s\n", addr);
-}
-
 static inline unsigned long print_context_stack(struct thread_info *tinfo,
                                unsigned long *stack, unsigned long ebp,
-                               char *log_lvl)
+                               struct stacktrace_ops *ops, void *data)
 {
        unsigned long addr;
 
 #ifdef CONFIG_FRAME_POINTER
        while (valid_stack_ptr(tinfo, (void *)ebp)) {
                addr = *(unsigned long *)(ebp + 4);
-               print_addr_and_symbol(addr, log_lvl);
+               ops->address(data, addr);
                /*
                 * break out of recursive entries (such as
                 * end_of_stack_stop_unwind_function):
@@ -146,30 +143,37 @@ static inline unsigned long print_context_stack(struct thread_info *tinfo,
        while (valid_stack_ptr(tinfo, stack)) {
                addr = *stack++;
                if (__kernel_text_address(addr))
-                       print_addr_and_symbol(addr, log_lvl);
+                       ops->address(data, addr);
        }
 #endif
        return ebp;
 }
 
+struct ops_and_data {
+       struct stacktrace_ops *ops;
+       void *data;
+};
+
 static asmlinkage int
-show_trace_unwind(struct unwind_frame_info *info, void *log_lvl)
+dump_trace_unwind(struct unwind_frame_info *info, void *data)
 {
+       struct ops_and_data *oad = (struct ops_and_data *)data;
        int n = 0;
 
        while (unwind(info) == 0 && UNW_PC(info)) {
                n++;
-               print_addr_and_symbol(UNW_PC(info), log_lvl);
+               oad->ops->address(oad->data, UNW_PC(info));
                if (arch_unw_user_mode(info))
                        break;
        }
        return n;
 }
 
-static void show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,
-                              unsigned long *stack, char *log_lvl)
+void dump_trace(struct task_struct *task, struct pt_regs *regs,
+               unsigned long *stack,
+               struct stacktrace_ops *ops, void *data)
 {
-       unsigned long ebp;
+       unsigned long ebp = 0;
 
        if (!task)
                task = current;
@@ -177,55 +181,116 @@ static void show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,
        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, task, regs) == 0)
-                               unw_ret = show_trace_unwind(&info, log_lvl);
+                               unw_ret = dump_trace_unwind(&info, &oad);
                } else if (task == current)
-                       unw_ret = unwind_init_running(&info, show_trace_unwind, log_lvl);
+                       unw_ret = unwind_init_running(&info, dump_trace_unwind, &oad);
                else {
                        if (unwind_init_blocked(&info, task) == 0)
-                               unw_ret = show_trace_unwind(&info, log_lvl);
+                               unw_ret = dump_trace_unwind(&info, &oad);
                }
-               if (unw_ret > 0 && !arch_unw_user_mode(&info)) {
-#ifdef CONFIG_STACK_UNWIND
-                       print_symbol("DWARF2 unwinder stuck at %s\n",
-                                    UNW_PC(&info));
-                       if (call_trace == 1) {
-                               printk("Leftover inexact backtrace:\n");
-                               if (UNW_SP(&info))
+               if (unw_ret > 0) {
+                       if (call_trace == 1 && !arch_unw_user_mode(&info)) {
+                               ops->warning_symbol(data, "DWARF2 unwinder stuck at %s\n",
+                                            UNW_PC(&info));
+                               if (UNW_SP(&info) >= PAGE_OFFSET) {
+                                       ops->warning(data, "Leftover inexact backtrace:\n");
                                        stack = (void *)UNW_SP(&info);
-                       } else if (call_trace > 1)
+                                       if (!stack)
+                                               return;
+                                       ebp = UNW_FP(&info);
+                               } else
+                                       ops->warning(data, "Full inexact backtrace again:\n");
+                       } else if (call_trace >= 1)
                                return;
                        else
-                               printk("Full inexact backtrace again:\n");
-#else
-                       printk("Inexact backtrace:\n");
-#endif
-               }
+                               ops->warning(data, "Full inexact backtrace again:\n");
+               } else
+                       ops->warning(data, "Inexact backtrace:\n");
+       }
+       if (!stack) {
+               unsigned long dummy;
+               stack = &dummy;
+               if (task && task != current)
+                       stack = (unsigned long *)task->thread.esp;
        }
 
-       if (task == current) {
-               /* Grab ebp right from our regs */
-               asm ("movl %%ebp, %0" : "=r" (ebp) : );
-       } else {
-               /* ebp is the last reg pushed by switch_to */
-               ebp = *(unsigned long *) task->thread.esp;
+#ifdef CONFIG_FRAME_POINTER
+       if (!ebp) {
+               if (task == current) {
+                       /* Grab ebp right from our regs */
+                       asm ("movl %%ebp, %0" : "=r" (ebp) : );
+               } else {
+                       /* ebp is the last reg pushed by switch_to */
+                       ebp = *(unsigned long *) task->thread.esp;
+               }
        }
+#endif
 
        while (1) {
                struct thread_info *context;
                context = (struct thread_info *)
                        ((unsigned long)stack & (~(THREAD_SIZE - 1)));
-               ebp = print_context_stack(context, stack, ebp, log_lvl);
+               ebp = print_context_stack(context, stack, ebp, ops, data);
+               /* Should be after the line below, but somewhere
+                  in early boot context comes out corrupted and we
+                  can't reference it -AK */
+               if (ops->stack(data, "IRQ") < 0)
+                       break;
                stack = (unsigned long*)context->previous_esp;
                if (!stack)
                        break;
-               printk("%s =======================\n", log_lvl);
        }
 }
+EXPORT_SYMBOL(dump_trace);
+
+static void
+print_trace_warning_symbol(void *data, char *msg, unsigned long symbol)
+{
+       printk(data);
+       print_symbol(msg, symbol);
+       printk("\n");
+}
+
+static void print_trace_warning(void *data, char *msg)
+{
+       printk("%s%s\n", (char *)data, msg);
+}
+
+static int print_trace_stack(void *data, char *name)
+{
+       return 0;
+}
 
-void show_trace(struct task_struct *task, struct pt_regs *regs, unsigned long * stack)
+/*
+ * Print one address/symbol entries per line.
+ */
+static void print_trace_address(void *data, unsigned long addr)
+{
+       printk("%s [<%08lx>] ", (char *)data, addr);
+       print_symbol("%s\n", 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,
+};
+
+static void
+show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,
+                  unsigned long * stack, char *log_lvl)
+{
+       dump_trace(task, regs, stack, &print_trace_ops, log_lvl);
+       printk("%s =======================\n", log_lvl);
+}
+
+void show_trace(struct task_struct *task, struct pt_regs *regs,
+               unsigned long * stack)
 {
        show_trace_log_lvl(task, regs, stack, "");
 }
@@ -288,8 +353,9 @@ void show_registers(struct pt_regs *regs)
                ss = regs->xss & 0xffff;
        }
        print_modules();
-       printk(KERN_EMERG "CPU:    %d\nEIP:    %04x:[<%08lx>]    %s VLI\n"
-                       "EFLAGS: %08lx   (%s %.*s) \n",
+       printk(KERN_EMERG "CPU:    %d\n"
+               KERN_EMERG "EIP:    %04x:[<%08lx>]    %s VLI\n"
+               KERN_EMERG "EFLAGS: %08lx   (%s %.*s)\n",
                smp_processor_id(), 0xffff & regs->xcs, regs->eip,
                print_tainted(), regs->eflags, system_utsname.release,
                (int)strcspn(system_utsname.version, " "),
@@ -310,6 +376,8 @@ void show_registers(struct pt_regs *regs)
         */
        if (in_kernel) {
                u8 __user *eip;
+               int code_bytes = 64;
+               unsigned char c;
 
                printk("\n" KERN_EMERG "Stack: ");
                show_stack_log_lvl(NULL, regs, (unsigned long *)esp, KERN_EMERG);
@@ -317,9 +385,12 @@ void show_registers(struct pt_regs *regs)
                printk(KERN_EMERG "Code: ");
 
                eip = (u8 __user *)regs->eip - 43;
-               for (i = 0; i < 64; i++, eip++) {
-                       unsigned char c;
-
+               if (eip < (u8 __user *)PAGE_OFFSET || __get_user(c, eip)) {
+                       /* try starting at EIP */
+                       eip = (u8 __user *)regs->eip;
+                       code_bytes = 32;
+               }
+               for (i = 0; i < code_bytes; i++, eip++) {
                        if (eip < (u8 __user *)PAGE_OFFSET || __get_user(c, eip)) {
                                printk(" Bad EIP value.");
                                break;
@@ -340,7 +411,7 @@ static void handle_BUG(struct pt_regs *regs)
 
        if (eip < PAGE_OFFSET)
                return;
-       if (__get_user(ud2, (unsigned short __user *)eip))
+       if (probe_kernel_address((unsigned short __user *)eip, ud2))
                return;
        if (ud2 != 0x0b0f)
                return;
@@ -353,7 +424,8 @@ static void handle_BUG(struct pt_regs *regs)
                char *file;
                char c;
 
-               if (__get_user(line, (unsigned short __user *)(eip + 2)))
+               if (probe_kernel_address((unsigned short __user *)(eip + 2),
+                                       line))
                        break;
                if (__get_user(file, (char * __user *)(eip + 4)) ||
                    (unsigned long)file < PAGE_OFFSET || __get_user(c, file))
@@ -454,7 +526,7 @@ void die(const char * str, struct pt_regs * regs, long err)
                panic("Fatal exception in interrupt");
 
        if (panic_on_oops)
-               panic("Fatal exception: panic_on_oops");
+               panic("Fatal exception");
 
        oops_exit();
        do_exit(SIGSEGV);
@@ -626,18 +698,24 @@ gp_in_kernel:
        }
 }
 
-static void mem_parity_error(unsigned char reason, struct pt_regs * regs)
+static __kprobes void
+mem_parity_error(unsigned char reason, struct pt_regs * regs)
 {
-       printk(KERN_EMERG "Uhhuh. NMI received. Dazed and confused, but trying "
-                       "to continue\n");
+       printk(KERN_EMERG "Uhhuh. NMI received for unknown reason %02x on "
+               "CPU %d.\n", reason, smp_processor_id());
        printk(KERN_EMERG "You probably have a hardware problem with your RAM "
                        "chips\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. */
        clear_mem_error(reason);
 }
 
-static void io_check_error(unsigned char reason, struct pt_regs * regs)
+static __kprobes void
+io_check_error(unsigned char reason, struct pt_regs * regs)
 {
        unsigned long i;
 
@@ -653,7 +731,8 @@ static void io_check_error(unsigned char reason, struct pt_regs * regs)
        outb(reason, 0x61);
 }
 
-static void unknown_nmi_error(unsigned char reason, struct pt_regs * regs)
+static __kprobes void
+unknown_nmi_error(unsigned char reason, struct pt_regs * regs)
 {
 #ifdef CONFIG_MCA
        /* Might actually be able to figure out what the guilty party
@@ -663,15 +742,18 @@ static void unknown_nmi_error(unsigned char reason, struct pt_regs * regs)
                return;
        }
 #endif
-       printk("Uhhuh. NMI received for unknown reason %02x on CPU %d.\n",
-               reason, smp_processor_id());
-       printk("Dazed and confused, but trying to continue\n");
-       printk("Do you have a strange power saving mode enabled?\n");
+       printk(KERN_EMERG "Uhhuh. NMI received for unknown reason %02x on "
+               "CPU %d.\n", reason, smp_processor_id());
+       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");
 }
 
 static DEFINE_SPINLOCK(nmi_print_lock);
 
-void die_nmi (struct pt_regs *regs, const char *msg)
+void __kprobes die_nmi(struct pt_regs *regs, const char *msg)
 {
        if (notify_die(DIE_NMIWATCHDOG, msg, regs, 0, 2, SIGINT) ==
            NOTIFY_STOP)
@@ -703,7 +785,7 @@ void die_nmi (struct pt_regs *regs, const char *msg)
        do_exit(SIGSEGV);
 }
 
-static void default_do_nmi(struct pt_regs * regs)
+static __kprobes void default_do_nmi(struct pt_regs * regs)
 {
        unsigned char reason = 0;
 
@@ -720,12 +802,12 @@ static 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) {
-                       nmi_watchdog_tick(regs);
+               if (nmi_watchdog_tick(regs, reason))
                        return;
-               }
+               if (!do_nmi_callback(regs, smp_processor_id()))
 #endif
-               unknown_nmi_error(reason, regs);
+                       unknown_nmi_error(reason, regs);
+
                return;
        }
        if (notify_die(DIE_NMI, "nmi", regs, reason, 2, SIGINT) == NOTIFY_STOP)
@@ -741,14 +823,7 @@ static void default_do_nmi(struct pt_regs * regs)
        reassert_nmi();
 }
 
-static int dummy_nmi_callback(struct pt_regs * regs, int cpu)
-{
-       return 0;
-}
-static nmi_callback_t nmi_callback = dummy_nmi_callback;
-fastcall void do_nmi(struct pt_regs * regs, long error_code)
+fastcall __kprobes void do_nmi(struct pt_regs * regs, long error_code)
 {
        int cpu;
 
@@ -758,25 +833,11 @@ fastcall void do_nmi(struct pt_regs * regs, long error_code)
 
        ++nmi_count(cpu);
 
-       if (!rcu_dereference(nmi_callback)(regs, cpu))
-               default_do_nmi(regs);
+       default_do_nmi(regs);
 
        nmi_exit();
 }
 
-void set_nmi_callback(nmi_callback_t callback)
-{
-       vmalloc_sync_all();
-       rcu_assign_pointer(nmi_callback, callback);
-}
-EXPORT_SYMBOL_GPL(set_nmi_callback);
-
-void unset_nmi_callback(void)
-{
-       nmi_callback = dummy_nmi_callback;
-}
-EXPORT_SYMBOL_GPL(unset_nmi_callback);
-
 #ifdef CONFIG_KPROBES
 fastcall void __kprobes do_int3(struct pt_regs *regs, long error_code)
 {
@@ -1116,20 +1177,6 @@ void __init trap_init_f00f_bug(void)
 }
 #endif
 
-#define _set_gate(gate_addr,type,dpl,addr,seg) \
-do { \
-  int __d0, __d1; \
-  __asm__ __volatile__ ("movw %%dx,%%ax\n\t" \
-       "movw %4,%%dx\n\t" \
-       "movl %%eax,%0\n\t" \
-       "movl %%edx,%1" \
-       :"=m" (*((long *) (gate_addr))), \
-        "=m" (*(1+(long *) (gate_addr))), "=&a" (__d0), "=&d" (__d1) \
-       :"i" ((short) (0x8000+(dpl<<13)+(type<<8))), \
-        "3" ((char *) (addr)),"2" ((seg) << 16)); \
-} while (0)
-
-
 /*
  * This needs to use 'idt_table' rather than 'idt', and
  * thus use the _nonmapped_ version of the IDT, as the
@@ -1138,7 +1185,7 @@ do { \
  */
 void set_intr_gate(unsigned int n, void *addr)
 {
-       _set_gate(idt_table+n,14,0,addr,__KERNEL_CS);
+       _set_gate(n, DESCTYPE_INT, addr, __KERNEL_CS);
 }
 
 /*
@@ -1146,22 +1193,22 @@ void set_intr_gate(unsigned int n, void *addr)
  */
 static inline void set_system_intr_gate(unsigned int n, void *addr)
 {
-       _set_gate(idt_table+n, 14, 3, addr, __KERNEL_CS);
+       _set_gate(n, DESCTYPE_INT | DESCTYPE_DPL3, addr, __KERNEL_CS);
 }
 
 static void __init set_trap_gate(unsigned int n, void *addr)
 {
-       _set_gate(idt_table+n,15,0,addr,__KERNEL_CS);
+       _set_gate(n, DESCTYPE_TRAP, addr, __KERNEL_CS);
 }
 
 static void __init set_system_gate(unsigned int n, void *addr)
 {
-       _set_gate(idt_table+n,15,3,addr,__KERNEL_CS);
+       _set_gate(n, DESCTYPE_TRAP | DESCTYPE_DPL3, addr, __KERNEL_CS);
 }
 
 static void __init set_task_gate(unsigned int n, unsigned int gdt_entry)
 {
-       _set_gate(idt_table+n,5,0,0,(gdt_entry<<3));
+       _set_gate(n, DESCTYPE_TASK, (void *)0, (gdt_entry<<3));
 }
 
 
@@ -1241,6 +1288,7 @@ static int __init kstack_setup(char *s)
 }
 __setup("kstack=", kstack_setup);
 
+#ifdef CONFIG_STACK_UNWIND
 static int __init call_trace_setup(char *s)
 {
        if (strcmp(s, "old") == 0)
@@ -1254,3 +1302,4 @@ static int __init call_trace_setup(char *s)
        return 1;
 }
 __setup("call_trace=", call_trace_setup);
+#endif