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Diffstat (limited to 'arch/i386/kernel/traps.c')
-rw-r--r--arch/i386/kernel/traps.c204
1 files changed, 44 insertions, 160 deletions
diff --git a/arch/i386/kernel/traps.c b/arch/i386/kernel/traps.c
index fe9c5e8e7e6..0efad8aeb41 100644
--- a/arch/i386/kernel/traps.c
+++ b/arch/i386/kernel/traps.c
@@ -29,6 +29,8 @@
#include <linux/kexec.h>
#include <linux/unwind.h>
#include <linux/uaccess.h>
+#include <linux/nmi.h>
+#include <linux/bug.h>
#ifdef CONFIG_EISA
#include <linux/ioport.h>
@@ -61,9 +63,6 @@ int panic_on_unrecovered_nmi;
asmlinkage int system_call(void);
-struct desc_struct default_ldt[] = { { 0, 0 }, { 0, 0 }, { 0, 0 },
- { 0, 0 }, { 0, 0 } };
-
/* Do we ignore FPU interrupts ? */
char ignore_fpu_irq = 0;
@@ -94,12 +93,7 @@ asmlinkage void alignment_check(void);
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
+int kstack_depth_to_print = 24;
ATOMIC_NOTIFIER_HEAD(i386die_chain);
int register_die_notifier(struct notifier_block *nb)
@@ -153,25 +147,7 @@ static inline unsigned long print_context_stack(struct thread_info *tinfo,
return ebp;
}
-struct ops_and_data {
- struct stacktrace_ops *ops;
- void *data;
-};
-
-static asmlinkage int
-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++;
- oad->ops->address(oad->data, UNW_PC(info));
- if (arch_unw_user_mode(info))
- break;
- }
- return n;
-}
+#define MSG(msg) ops->warning(data, msg)
void dump_trace(struct task_struct *task, struct pt_regs *regs,
unsigned long *stack,
@@ -182,39 +158,6 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
if (!task)
task = 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, task, regs) == 0)
- unw_ret = dump_trace_unwind(&info, &oad);
- } else if (task == current)
- unw_ret = unwind_init_running(&info, dump_trace_unwind, &oad);
- else {
- if (unwind_init_blocked(&info, task) == 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\n",
- UNW_PC(&info));
- if (UNW_SP(&info) >= PAGE_OFFSET) {
- ops->warning(data, "Leftover inexact backtrace:\n");
- stack = (void *)UNW_SP(&info);
- if (!stack)
- return;
- ebp = UNW_FP(&info);
- } else
- ops->warning(data, "Full inexact backtrace again:\n");
- } else if (call_trace >= 1)
- return;
- else
- ops->warning(data, "Full inexact backtrace again:\n");
- } else
- ops->warning(data, "Inexact backtrace:\n");
- }
if (!stack) {
unsigned long dummy;
stack = &dummy;
@@ -247,6 +190,7 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
stack = (unsigned long*)context->previous_esp;
if (!stack)
break;
+ touch_nmi_watchdog();
}
}
EXPORT_SYMBOL(dump_trace);
@@ -379,7 +323,7 @@ void show_registers(struct pt_regs *regs)
* time of the fault..
*/
if (in_kernel) {
- u8 __user *eip;
+ u8 *eip;
int code_bytes = 64;
unsigned char c;
@@ -388,18 +332,20 @@ void show_registers(struct pt_regs *regs)
printk(KERN_EMERG "Code: ");
- eip = (u8 __user *)regs->eip - 43;
- if (eip < (u8 __user *)PAGE_OFFSET || __get_user(c, eip)) {
+ eip = (u8 *)regs->eip - 43;
+ if (eip < (u8 *)PAGE_OFFSET ||
+ probe_kernel_address(eip, c)) {
/* try starting at EIP */
- eip = (u8 __user *)regs->eip;
+ eip = (u8 *)regs->eip;
code_bytes = 32;
}
for (i = 0; i < code_bytes; i++, eip++) {
- if (eip < (u8 __user *)PAGE_OFFSET || __get_user(c, eip)) {
+ if (eip < (u8 *)PAGE_OFFSET ||
+ probe_kernel_address(eip, c)) {
printk(" Bad EIP value.");
break;
}
- if (eip == (u8 __user *)regs->eip)
+ if (eip == (u8 *)regs->eip)
printk("<%02x> ", c);
else
printk("%02x ", c);
@@ -408,43 +354,22 @@ void show_registers(struct pt_regs *regs)
printk("\n");
}
-static void handle_BUG(struct pt_regs *regs)
+int is_valid_bugaddr(unsigned long eip)
{
- unsigned long eip = regs->eip;
unsigned short ud2;
if (eip < PAGE_OFFSET)
- return;
- if (probe_kernel_address((unsigned short __user *)eip, ud2))
- return;
- if (ud2 != 0x0b0f)
- return;
-
- printk(KERN_EMERG "------------[ cut here ]------------\n");
+ return 0;
+ if (probe_kernel_address((unsigned short *)eip, ud2))
+ return 0;
-#ifdef CONFIG_DEBUG_BUGVERBOSE
- do {
- unsigned short line;
- char *file;
- char c;
-
- 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))
- 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");
+ return ud2 == 0x0b0f;
}
-/* This is gone through when something in the kernel
- * has done something bad and is about to be terminated.
-*/
+/*
+ * This is gone through when something in the kernel has done something bad and
+ * is about to be terminated.
+ */
void die(const char * str, struct pt_regs * regs, long err)
{
static struct {
@@ -452,7 +377,7 @@ void die(const char * str, struct pt_regs * regs, long err)
u32 lock_owner;
int lock_owner_depth;
} die = {
- .lock = SPIN_LOCK_UNLOCKED,
+ .lock = __SPIN_LOCK_UNLOCKED(die.lock),
.lock_owner = -1,
.lock_owner_depth = 0
};
@@ -476,7 +401,8 @@ void die(const char * str, struct pt_regs * regs, long err)
unsigned long esp;
unsigned short ss;
- handle_BUG(regs);
+ report_bug(regs->eip);
+
printk(KERN_EMERG "%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
#ifdef CONFIG_PREEMPT
printk(KERN_EMERG "PREEMPT ");
@@ -707,8 +633,7 @@ mem_parity_error(unsigned char reason, struct pt_regs * regs)
{
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");
+ printk(KERN_EMERG "You have some hardware problem, likely on the PCI bus.\n");
if (panic_on_unrecovered_nmi)
panic("NMI: Not continuing");
@@ -773,7 +698,6 @@ void __kprobes die_nmi(struct pt_regs *regs, const char *msg)
printk(" on CPU%d, eip %08lx, registers:\n",
smp_processor_id(), regs->eip);
show_registers(regs);
- printk(KERN_EMERG "console shuts up ...\n");
console_silent();
spin_unlock(&nmi_print_lock);
bust_spinlocks(0);
@@ -1088,49 +1012,24 @@ fastcall void do_spurious_interrupt_bug(struct pt_regs * regs,
#endif
}
-fastcall void setup_x86_bogus_stack(unsigned char * stk)
+fastcall unsigned long patch_espfix_desc(unsigned long uesp,
+ unsigned long kesp)
{
- unsigned long *switch16_ptr, *switch32_ptr;
- struct pt_regs *regs;
- unsigned long stack_top, stack_bot;
- unsigned short iret_frame16_off;
int cpu = smp_processor_id();
- /* reserve the space on 32bit stack for the magic switch16 pointer */
- memmove(stk, stk + 8, sizeof(struct pt_regs));
- switch16_ptr = (unsigned long *)(stk + sizeof(struct pt_regs));
- regs = (struct pt_regs *)stk;
- /* now the switch32 on 16bit stack */
- stack_bot = (unsigned long)&per_cpu(cpu_16bit_stack, cpu);
- stack_top = stack_bot + CPU_16BIT_STACK_SIZE;
- switch32_ptr = (unsigned long *)(stack_top - 8);
- iret_frame16_off = CPU_16BIT_STACK_SIZE - 8 - 20;
- /* copy iret frame on 16bit stack */
- memcpy((void *)(stack_bot + iret_frame16_off), &regs->eip, 20);
- /* fill in the switch pointers */
- switch16_ptr[0] = (regs->esp & 0xffff0000) | iret_frame16_off;
- switch16_ptr[1] = __ESPFIX_SS;
- switch32_ptr[0] = (unsigned long)stk + sizeof(struct pt_regs) +
- 8 - CPU_16BIT_STACK_SIZE;
- switch32_ptr[1] = __KERNEL_DS;
-}
-
-fastcall unsigned char * fixup_x86_bogus_stack(unsigned short sp)
-{
- unsigned long *switch32_ptr;
- unsigned char *stack16, *stack32;
- unsigned long stack_top, stack_bot;
- int len;
- int cpu = smp_processor_id();
- stack_bot = (unsigned long)&per_cpu(cpu_16bit_stack, cpu);
- stack_top = stack_bot + CPU_16BIT_STACK_SIZE;
- switch32_ptr = (unsigned long *)(stack_top - 8);
- /* copy the data from 16bit stack to 32bit stack */
- len = CPU_16BIT_STACK_SIZE - 8 - sp;
- stack16 = (unsigned char *)(stack_bot + sp);
- stack32 = (unsigned char *)
- (switch32_ptr[0] + CPU_16BIT_STACK_SIZE - 8 - len);
- memcpy(stack32, stack16, len);
- return stack32;
+ struct Xgt_desc_struct *cpu_gdt_descr = &per_cpu(cpu_gdt_descr, cpu);
+ struct desc_struct *gdt = (struct desc_struct *)cpu_gdt_descr->address;
+ unsigned long base = (kesp - uesp) & -THREAD_SIZE;
+ unsigned long new_kesp = kesp - base;
+ unsigned long lim_pages = (new_kesp | (THREAD_SIZE - 1)) >> PAGE_SHIFT;
+ __u64 desc = *(__u64 *)&gdt[GDT_ENTRY_ESPFIX_SS];
+ /* Set up base for espfix segment */
+ desc &= 0x00f0ff0000000000ULL;
+ desc |= ((((__u64)base) << 16) & 0x000000ffffff0000ULL) |
+ ((((__u64)base) << 32) & 0xff00000000000000ULL) |
+ ((((__u64)lim_pages) << 32) & 0x000f000000000000ULL) |
+ (lim_pages & 0xffff);
+ *(__u64 *)&gdt[GDT_ENTRY_ESPFIX_SS] = desc;
+ return new_kesp;
}
/*
@@ -1143,7 +1042,7 @@ fastcall unsigned char * fixup_x86_bogus_stack(unsigned short sp)
* Must be called with kernel preemption disabled (in this case,
* local interrupts are disabled at the call-site in entry.S).
*/
-asmlinkage void math_state_restore(struct pt_regs regs)
+asmlinkage void math_state_restore(void)
{
struct thread_info *thread = current_thread_info();
struct task_struct *tsk = thread->task;
@@ -1153,6 +1052,7 @@ asmlinkage void math_state_restore(struct pt_regs regs)
init_fpu(tsk);
restore_fpu(tsk);
thread->status |= TS_USEDFPU; /* So we fnsave on switch_to() */
+ tsk->fpu_counter++;
}
#ifndef CONFIG_MATH_EMULATION
@@ -1291,19 +1191,3 @@ static int __init kstack_setup(char *s)
return 1;
}
__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, "newfallback") == 0)
- call_trace = 1;
- else if (strcmp(s, "new") == 2)
- call_trace = 2;
- return 1;
-}
-__setup("call_trace=", call_trace_setup);
-#endif