diff options
Diffstat (limited to 'arch/i386/kernel/traps.c')
-rw-r--r-- | arch/i386/kernel/traps.c | 204 |
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), ®s->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 |