[PATCH] x86: add a bootparameter to reserve high linear address space

[powerpc.git] / arch / i386 / kernel / traps.c

diff --git a/arch/i386/kernel/traps.c b/arch/i386/kernel/traps.c
index 2bf8b55..4fcc669 100644 (file)
--- a/arch/i386/kernel/traps.c
+++ b/arch/i386/kernel/traps.c
@@ -92,7 +92,11 @@ 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)
@@ -100,13 +104,13 @@ int register_die_notifier(struct notifier_block *nb)
        vmalloc_sync_all();
        return atomic_notifier_chain_register(&i386die_chain, nb);
 }
-EXPORT_SYMBOL(register_die_notifier);
+EXPORT_SYMBOL(register_die_notifier); /* used modular by kdb */
 
 int unregister_die_notifier(struct notifier_block *nb)
 {
        return atomic_notifier_chain_unregister(&i386die_chain, nb);
 }
-EXPORT_SYMBOL(unregister_die_notifier);
+EXPORT_SYMBOL(unregister_die_notifier); /* used modular by kdb */
 
 static inline int valid_stack_ptr(struct thread_info *tinfo, void *p)
 {
@@ -188,10 +192,20 @@ static void show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,
                                unw_ret = show_trace_unwind(&info, log_lvl);
                }
                if (unw_ret > 0) {
-                       if (call_trace > 0)
+                       if (call_trace == 1 && !arch_unw_user_mode(&info)) {
+                               print_symbol("DWARF2 unwinder stuck at %s\n",
+                                            UNW_PC(&info));
+                               if (UNW_SP(&info) >= PAGE_OFFSET) {
+                                       printk("Leftover inexact backtrace:\n");
+                                       stack = (void *)UNW_SP(&info);
+                               } else
+                                       printk("Full inexact backtrace again:\n");
+                       } else if (call_trace >= 1)
                                return;
-                       printk("%sLegacy call trace:\n", log_lvl);
-               }
+                       else
+                               printk("Full inexact backtrace again:\n");
+               } else
+                       printk("Inexact backtrace:\n");
        }
 
        if (task == current) {
@@ -299,6 +313,8 @@ 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);
@@ -306,9 +322,12 @@ 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;
@@ -324,35 +343,35 @@ void show_registers(struct pt_regs *regs)
 
 static void handle_BUG(struct pt_regs *regs)
 {
+       unsigned long eip = regs->eip;
        unsigned short ud2;
-       unsigned short line;
-       char *file;
-       char c;
-       unsigned long eip;
-
-       eip = regs->eip;
 
        if (eip < PAGE_OFFSET)
-               goto no_bug;
+               return;
        if (__get_user(ud2, (unsigned short __user *)eip))
-               goto no_bug;
+               return;
        if (ud2 != 0x0b0f)
-               goto no_bug;
-       if (__get_user(line, (unsigned short __user *)(eip + 2)))
-               goto bug;
-       if (__get_user(file, (char * __user *)(eip + 4)) ||
-               (unsigned long)file < PAGE_OFFSET || __get_user(c, file))
-               file = "<bad filename>";
+               return;
 
        printk(KERN_EMERG "------------[ cut here ]------------\n");
-       printk(KERN_EMERG "kernel BUG at %s:%d!\n", file, line);
 
-no_bug:
-       return;
+#ifdef CONFIG_DEBUG_BUGVERBOSE
+       do {
+               unsigned short line;
+               char *file;
+               char c;
 
-       /* Here we know it was a BUG but file-n-line is unavailable */
-bug:
-       printk(KERN_EMERG "Kernel BUG\n");
+               if (__get_user(line, (unsigned short __user *)(eip + 2)))
+                       break;
+               if (__get_user(file, (char * __user *)(eip + 4)) ||
+                   (unsigned long)file < PAGE_OFFSET || __get_user(c, file))
+                       file = "<bad filename>";
+
+               printk(KERN_EMERG "kernel BUG at %s:%d!\n", file, line);
+               return;
+       } while (0);
+#endif
+       printk(KERN_EMERG "Kernel BUG at [verbose debug info unavailable]\n");
 }
 
 /* This is gone through when something in the kernel
@@ -442,11 +461,9 @@ void die(const char * str, struct pt_regs * regs, long err)
        if (in_interrupt())
                panic("Fatal exception in interrupt");
 
-       if (panic_on_oops) {
-               printk(KERN_EMERG "Fatal exception: panic in 5 seconds\n");
-               ssleep(5);
+       if (panic_on_oops)
                panic("Fatal exception");
-       }
+
        oops_exit();
        do_exit(SIGSEGV);
 }
@@ -1232,14 +1249,18 @@ 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)
                call_trace = -1;
        else if (strcmp(s, "both") == 0)
                call_trace = 0;
-       else if (strcmp(s, "new") == 0)
+       else if (strcmp(s, "newfallback") == 0)
                call_trace = 1;
+       else if (strcmp(s, "new") == 2)
+               call_trace = 2;
        return 1;
 }
 __setup("call_trace=", call_trace_setup);
+#endif