Merge branch 'dbg-early-merge' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb

* 'dbg-early-merge' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb:
  echi-dbgp: Add kernel debugger support for the usb debug port
  earlyprintk,vga,kdb: Fix \b and \r for earlyprintk=vga with kdb
  kgdboc: Add ekgdboc for early use of the kernel debugger
  x86,early dr regs,kgdb: Allow kernel debugger early dr register access
  x86,kgdb: Implement early hardware breakpoint debugging
  x86, kgdb, init: Add early and late debug states
  x86, kgdb: early trap init for early debug

1 files changed, 17 insertions, 12 deletions

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index c1c00d0b1692..cc83a002786e 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1084,6 +1084,20 @@ static void clear_all_debug_regs(void)
         }
 }
 
+#ifdef CONFIG_KGDB
+/*
+ * Restore debug regs if using kgdbwait and you have a kernel debugger
+ * connection established.
+ */
+static void dbg_restore_debug_regs(void)
+{
+        if (unlikely(kgdb_connected && arch_kgdb_ops.correct_hw_break))
+                arch_kgdb_ops.correct_hw_break();
+}
+#else /* ! CONFIG_KGDB */
+#define dbg_restore_debug_regs()
+#endif /* ! CONFIG_KGDB */
+
 /*
  * cpu_init() initializes state that is per-CPU. Some data is already
  * initialized (naturally) in the bootstrap process, such as the GDT
@@ -1174,18 +1188,8 @@ void __cpuinit cpu_init(void)
         load_TR_desc();
         load_LDT(&init_mm.context);
 
-#ifdef CONFIG_KGDB
-        /*
-         * If the kgdb is connected no debug regs should be altered.  This
-         * is only applicable when KGDB and a KGDB I/O module are built
-         * into the kernel and you are using early debugging with
-         * kgdbwait. KGDB will control the kernel HW breakpoint registers.
-         */
-        if (kgdb_connected && arch_kgdb_ops.correct_hw_break)
-                arch_kgdb_ops.correct_hw_break();
-        else
-#endif
-                clear_all_debug_regs();
+        clear_all_debug_regs();
+        dbg_restore_debug_regs();
 
         fpu_init();
 
@@ -1239,6 +1243,7 @@ void __cpuinit cpu_init(void)
 #endif
 
         clear_all_debug_regs();
+        dbg_restore_debug_regs();
 
         /*
          * Force FPU initialization: