x86 single_step: TIF_FORCED_TF

[pandora-kernel.git] / arch / x86 / kernel / traps_64.c

diff --git a/arch/x86/kernel/traps_64.c b/arch/x86/kernel/traps_64.c
index d11525a..874aca3 100644 (file)
--- a/arch/x86/kernel/traps_64.c
+++ b/arch/x86/kernel/traps_64.c
@@ -461,14 +461,6 @@ int is_valid_bugaddr(unsigned long rip)
        return ud2 == 0x0b0f;
 }
 
-#ifdef CONFIG_BUG
-void out_of_line_bug(void)
-{ 
-       BUG(); 
-} 
-EXPORT_SYMBOL(out_of_line_bug);
-#endif
-
 static raw_spinlock_t die_lock = __RAW_SPIN_LOCK_UNLOCKED;
 static int die_owner = -1;
 static unsigned int die_nest_count;
@@ -635,6 +627,7 @@ asmlinkage void do_##name(struct pt_regs * regs, long error_code) \
        info.si_errno = 0; \
        info.si_code = sicode; \
        info.si_addr = (void __user *)siaddr; \
+       trace_hardirqs_fixup(); \
        if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) \
                                                        == NOTIFY_STOP) \
                return; \
@@ -872,27 +865,14 @@ asmlinkage void __kprobes do_debug(struct pt_regs * regs,
 
        tsk->thread.debugreg6 = condition;
 
-       /* Mask out spurious TF errors due to lazy TF clearing */
+
+       /*
+        * Single-stepping through TF: make sure we ignore any events in
+        * kernel space (but re-enable TF when returning to user mode).
+        */
        if (condition & DR_STEP) {
-               /*
-                * The TF error should be masked out only if the current
-                * process is not traced and if the TRAP flag has been set
-                * previously by a tracing process (condition detected by
-                * the PT_DTRACE flag); remember that the i386 TRAP flag
-                * can be modified by the process itself in user mode,
-                * allowing programs to debug themselves without the ptrace()
-                * interface.
-                */
                 if (!user_mode(regs))
                        goto clear_TF_reenable;
-               /*
-                * Was the TF flag set by a debugger? If so, clear it now,
-                * so that register information is correct.
-                */
-               if (tsk->ptrace & PT_DTRACE) {
-                       regs->eflags &= ~TF_MASK;
-                       tsk->ptrace &= ~PT_DTRACE;
-               }
        }
 
        /* Ok, finally something we can handle */