7 files changed, 37 insertions, 48 deletions

diff --git a/arch/x86_64/kernel/e820.c b/arch/x86_64/kernel/e820.c
index e56c2adf57a4..764bf23c7103 100644
--- a/arch/x86_64/kernel/e820.c
+++ b/arch/x86_64/kernel/e820.c
@@ -71,7 +71,11 @@ static inline int bad_addr(unsigned long *addrp, unsigned long size)
 #endif
         /* kernel code + 640k memory hole (later should not be needed, but 
            be paranoid for now) */
-        if (last >= 640*1024 && addr < __pa_symbol(&_end)) { 
+        if (last >= 640*1024 && addr < 1024*1024) {
+                *addrp = 1024*1024;
+                return 1;
+        }
+        if (last >= __pa_symbol(&_text) && last < __pa_symbol(&_end)) {
                 *addrp = __pa_symbol(&_end);
                 return 1;
         }
@@ -104,35 +108,6 @@ e820_any_mapped(unsigned long start, unsigned long end, unsigned type)
         return 0;
 }
 
-/*
- * This function checks if the entire range <start,end> is mapped with type.
- *
- * Note: this function only works correct if the e820 table is sorted and
- * not-overlapping, which is the case
- */
-int __init e820_all_mapped(unsigned long start, unsigned long end, unsigned type)
-{
-        int i;
-        for (i = 0; i < e820.nr_map; i++) {
-                struct e820entry *ei = &e820.map[i];
-                if (type && ei->type != type)
-                        continue;
-                /* is the region (part) in overlap with the current region ?*/
-                if (ei->addr >= end || ei->addr + ei->size <= start)
-                        continue;
-
-                /* if the region is at the beginning of <start,end> we move
-                 * start to the end of the region since it's ok until there
-                 */
-                if (ei->addr <= start)
-                        start = ei->addr + ei->size;
-                /* if start is now at or beyond end, we're done, full coverage */
-                if (start >= end)
-                        return 1; /* we're done */
-        }
-        return 0;
-}
-
 /* 
  * Find a free area in a specific range. 
  */ 
diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S
index 6f810424df44..aa8d8939abc1 100644
--- a/arch/x86_64/kernel/entry.S
+++ b/arch/x86_64/kernel/entry.S
@@ -973,6 +973,8 @@ ENTRY(kernel_thread)
 ENDPROC(kernel_thread)
         
 child_rip:
+        pushq $0                # fake return address
+        CFI_STARTPROC
         /*
          * Here we are in the child and the registers are set as they were
          * at kernel_thread() invocation in the parent.
@@ -983,6 +985,7 @@ child_rip:
         # exit
         xorl %edi, %edi
         call do_exit
+        CFI_ENDPROC
 ENDPROC(child_rip)
 
 /*
diff --git a/arch/x86_64/kernel/head.S b/arch/x86_64/kernel/head.S
index 6df05e6034fa..c9739ca81d06 100644
--- a/arch/x86_64/kernel/head.S
+++ b/arch/x86_64/kernel/head.S
@@ -191,6 +191,7 @@ startup_64:
          * jump
          */
         movq    initial_code(%rip),%rax
+        pushq   $0              # fake return address
         jmp     *%rax
 
         /* SMP bootup changes these two */
diff --git a/arch/x86_64/kernel/init_task.c b/arch/x86_64/kernel/init_task.c
index ce31d904d601..3dc5854ba21e 100644
--- a/arch/x86_64/kernel/init_task.c
+++ b/arch/x86_64/kernel/init_task.c
@@ -46,4 +46,9 @@ EXPORT_SYMBOL(init_task);
  */ 
 DEFINE_PER_CPU(struct tss_struct, init_tss) ____cacheline_internodealigned_in_smp = INIT_TSS;
 
+/* Copies of the original ist values from the tss are only accessed during
+ * debugging, no special alignment required.
+ */
+DEFINE_PER_CPU(struct orig_ist, orig_ist);
+
 #define ALIGN_TO_4K __attribute__((section(".data.init_task")))
diff --git a/arch/x86_64/kernel/setup.c b/arch/x86_64/kernel/setup.c
index 8a099ff1f8bc..34afad704824 100644
--- a/arch/x86_64/kernel/setup.c
+++ b/arch/x86_64/kernel/setup.c
@@ -521,8 +521,6 @@ static void discover_ebda(void)
 
 void __init setup_arch(char **cmdline_p)
 {
-        unsigned long kernel_end;
-
         ROOT_DEV = old_decode_dev(ORIG_ROOT_DEV);
         screen_info = SCREEN_INFO;
         edid_info = EDID_INFO;
@@ -596,8 +594,8 @@ void __init setup_arch(char **cmdline_p)
                                 (table_end - table_start) << PAGE_SHIFT);
 
         /* reserve kernel */
-        kernel_end = round_up(__pa_symbol(&_end),PAGE_SIZE);
-        reserve_bootmem_generic(HIGH_MEMORY, kernel_end - HIGH_MEMORY);
+        reserve_bootmem_generic(__pa_symbol(&_text),
+                                __pa_symbol(&_end) - __pa_symbol(&_text));
 
         /*
          * reserve physical page 0 - it's a special BIOS page on many boxes,
diff --git a/arch/x86_64/kernel/setup64.c b/arch/x86_64/kernel/setup64.c
index 6fe58a634b5f..417de564456e 100644
--- a/arch/x86_64/kernel/setup64.c
+++ b/arch/x86_64/kernel/setup64.c
@@ -189,6 +189,7 @@ void __cpuinit cpu_init (void)
 {
         int cpu = stack_smp_processor_id();
         struct tss_struct *t = &per_cpu(init_tss, cpu);
+        struct orig_ist *orig_ist = &per_cpu(orig_ist, cpu);
         unsigned long v; 
         char *estacks = NULL; 
         struct task_struct *me;
@@ -256,7 +257,7 @@ void __cpuinit cpu_init (void)
                         estacks += EXCEPTION_STKSZ;
                         break;
                 }
-                t->ist[v] = (unsigned long)estacks;
+                orig_ist->ist[v] = t->ist[v] = (unsigned long)estacks;
         }
 
         t->io_bitmap_base = offsetof(struct tss_struct, io_bitmap);
diff --git a/arch/x86_64/kernel/traps.c b/arch/x86_64/kernel/traps.c
index 4e9938dee060..b1249774d1e8 100644
--- a/arch/x86_64/kernel/traps.c
+++ b/arch/x86_64/kernel/traps.c
@@ -107,7 +107,11 @@ static inline void preempt_conditional_cli(struct pt_regs *regs)
 }
 
 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
 # include <linux/kallsyms.h>
@@ -174,7 +178,7 @@ static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack,
                         break;
 #endif
                 default:
-                        end = per_cpu(init_tss, cpu).ist[k];
+                        end = per_cpu(orig_ist, cpu).ist[k];
                         break;
                 }
                 /*
@@ -274,21 +278,21 @@ void show_trace(struct task_struct *tsk, struct pt_regs *regs, unsigned long * s
                         if (unwind_init_blocked(&info, tsk) == 0)
                                 unw_ret = show_trace_unwind(&info, NULL);
                 }
-                if (unw_ret > 0 && !arch_unw_user_mode(&info)) {
-#ifdef CONFIG_STACK_UNWIND
-                        unsigned long rip = info.regs.rip;
-                        print_symbol("DWARF2 unwinder stuck at %s\n", rip);
-                        if (call_trace == 1) {
-                                printk("Leftover inexact backtrace:\n");
-                                stack = (unsigned long *)info.regs.rsp;
-                        } else if (call_trace > 1)
+                if (unw_ret > 0) {
+                        if (call_trace == 1 && !arch_unw_user_mode(&info)) {
+                                print_symbol("DWARF2 unwinder stuck at %s\n",
+                                             UNW_PC(&info));
+                                if ((long)UNW_SP(&info) < 0) {
+                                        printk("Leftover inexact backtrace:\n");
+                                        stack = (unsigned long *)UNW_SP(&info);
+                                } else
+                                        printk("Full inexact backtrace again:\n");
+                        } else if (call_trace >= 1)
                                 return;
                         else
                                 printk("Full inexact backtrace again:\n");
-#else
+                } else
                         printk("Inexact backtrace:\n");
-#endif
-                }
         }
 
         /*
@@ -529,7 +533,7 @@ void __kprobes oops_end(unsigned long flags)
                 /* Nest count reaches zero, release the lock. */
                 spin_unlock_irqrestore(&die_lock, flags);
         if (panic_on_oops)
-                panic("Fatal exception: panic_on_oops");
+                panic("Fatal exception");
 }
 
 void __kprobes __die(const char * str, struct pt_regs * regs, long err)
@@ -1120,6 +1124,7 @@ 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)
@@ -1133,3 +1138,4 @@ static int __init call_trace_setup(char *s)
         return 1;
 }
 __setup("call_trace=", call_trace_setup);
+#endif