1 files changed, 57 insertions, 30 deletions

diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index 0d7c08784efb..0557f24c6bca 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -41,6 +41,7 @@
 #include <linux/delay.h>
 #include <linux/sched.h>
 #include <linux/sysrq.h>
+#include <linux/reboot.h>
 #include <linux/init.h>
 #include <linux/kgdb.h>
 #include <linux/kdb.h>
@@ -52,7 +53,6 @@
 #include <asm/cacheflush.h>
 #include <asm/byteorder.h>
 #include <linux/atomic.h>
-#include <asm/system.h>
 
 #include "debug_core.h"
 
@@ -75,6 +75,8 @@ static int			exception_level;
 struct kgdb_io          *dbg_io_ops;
 static DEFINE_SPINLOCK(kgdb_registration_lock);
 
+/* Action for the reboot notifiter, a global allow kdb to change it */
+static int kgdbreboot;
 /* kgdb console driver is loaded */
 static int kgdb_con_registered;
 /* determine if kgdb console output should be used */
@@ -96,6 +98,7 @@ static int __init opt_kgdb_con(char *str)
 early_param("kgdbcon", opt_kgdb_con);
 
 module_param(kgdb_use_con, int, 0644);
+module_param(kgdbreboot, int, 0644);
 
 /*
  * Holds information about breakpoints in a kernel. These breakpoints are
@@ -157,37 +160,39 @@ early_param("nokgdbroundup", opt_nokgdbroundup);
  * Weak aliases for breakpoint management,
  * can be overriden by architectures when needed:
  */
-int __weak kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr)
+int __weak kgdb_arch_set_breakpoint(struct kgdb_bkpt *bpt)
 {
         int err;
 
-        err = probe_kernel_read(saved_instr, (char *)addr, BREAK_INSTR_SIZE);
+        err = probe_kernel_read(bpt->saved_instr, (char *)bpt->bpt_addr,
+                                BREAK_INSTR_SIZE);
         if (err)
                 return err;
-
-        return probe_kernel_write((char *)addr, arch_kgdb_ops.gdb_bpt_instr,
-                                  BREAK_INSTR_SIZE);
+        err = probe_kernel_write((char *)bpt->bpt_addr,
+                                 arch_kgdb_ops.gdb_bpt_instr, BREAK_INSTR_SIZE);
+        return err;
 }
 
-int __weak kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle)
+int __weak kgdb_arch_remove_breakpoint(struct kgdb_bkpt *bpt)
 {
-        return probe_kernel_write((char *)addr,
-                                  (char *)bundle, BREAK_INSTR_SIZE);
+        return probe_kernel_write((char *)bpt->bpt_addr,
+                                  (char *)bpt->saved_instr, BREAK_INSTR_SIZE);
 }
 
 int __weak kgdb_validate_break_address(unsigned long addr)
 {
-        char tmp_variable[BREAK_INSTR_SIZE];
+        struct kgdb_bkpt tmp;
         int err;
-        /* Validate setting the breakpoint and then removing it.  In the
+        /* Validate setting the breakpoint and then removing it.  If the
          * remove fails, the kernel needs to emit a bad message because we
          * are deep trouble not being able to put things back the way we
          * found them.
          */
-        err = kgdb_arch_set_breakpoint(addr, tmp_variable);
+        tmp.bpt_addr = addr;
+        err = kgdb_arch_set_breakpoint(&tmp);
         if (err)
                 return err;
-        err = kgdb_arch_remove_breakpoint(addr, tmp_variable);
+        err = kgdb_arch_remove_breakpoint(&tmp);
         if (err)
                 printk(KERN_ERR "KGDB: Critical breakpoint error, kernel "
                    "memory destroyed at: %lx", addr);
@@ -231,7 +236,6 @@ static void kgdb_flush_swbreak_addr(unsigned long addr)
  */
 int dbg_activate_sw_breakpoints(void)
 {
-        unsigned long addr;
         int error;
         int ret = 0;
         int i;
@@ -240,16 +244,15 @@ int dbg_activate_sw_breakpoints(void)
                 if (kgdb_break[i].state != BP_SET)
                         continue;
 
-                addr = kgdb_break[i].bpt_addr;
-                error = kgdb_arch_set_breakpoint(addr,
-                                kgdb_break[i].saved_instr);
+                error = kgdb_arch_set_breakpoint(&kgdb_break[i]);
                 if (error) {
                         ret = error;
-                        printk(KERN_INFO "KGDB: BP install failed: %lx", addr);
+                        printk(KERN_INFO "KGDB: BP install failed: %lx",
+                               kgdb_break[i].bpt_addr);
                         continue;
                 }
 
-                kgdb_flush_swbreak_addr(addr);
+                kgdb_flush_swbreak_addr(kgdb_break[i].bpt_addr);
                 kgdb_break[i].state = BP_ACTIVE;
         }
         return ret;
@@ -298,7 +301,6 @@ int dbg_set_sw_break(unsigned long addr)
 
 int dbg_deactivate_sw_breakpoints(void)
 {
-        unsigned long addr;
         int error;
         int ret = 0;
         int i;
@@ -306,15 +308,14 @@ int dbg_deactivate_sw_breakpoints(void)
         for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
                 if (kgdb_break[i].state != BP_ACTIVE)
                         continue;
-                addr = kgdb_break[i].bpt_addr;
-                error = kgdb_arch_remove_breakpoint(addr,
-                                        kgdb_break[i].saved_instr);
+                error = kgdb_arch_remove_breakpoint(&kgdb_break[i]);
                 if (error) {
-                        printk(KERN_INFO "KGDB: BP remove failed: %lx\n", addr);
+                        printk(KERN_INFO "KGDB: BP remove failed: %lx\n",
+                               kgdb_break[i].bpt_addr);
                         ret = error;
                 }
 
-                kgdb_flush_swbreak_addr(addr);
+                kgdb_flush_swbreak_addr(kgdb_break[i].bpt_addr);
                 kgdb_break[i].state = BP_SET;
         }
         return ret;
@@ -348,7 +349,6 @@ int kgdb_isremovedbreak(unsigned long addr)
 
 int dbg_remove_all_break(void)
 {
-        unsigned long addr;
         int error;
         int i;
 
@@ -356,12 +356,10 @@ int dbg_remove_all_break(void)
         for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
                 if (kgdb_break[i].state != BP_ACTIVE)
                         goto setundefined;
-                addr = kgdb_break[i].bpt_addr;
-                error = kgdb_arch_remove_breakpoint(addr,
-                                kgdb_break[i].saved_instr);
+                error = kgdb_arch_remove_breakpoint(&kgdb_break[i]);
                 if (error)
                         printk(KERN_ERR "KGDB: breakpoint remove failed: %lx\n",
-                           addr);
+                               kgdb_break[i].bpt_addr);
 setundefined:
                 kgdb_break[i].state = BP_UNDEFINED;
         }
@@ -784,6 +782,33 @@ void __init dbg_late_init(void)
         kdb_init(KDB_INIT_FULL);
 }
 
+static int
+dbg_notify_reboot(struct notifier_block *this, unsigned long code, void *x)
+{
+        /*
+         * Take the following action on reboot notify depending on value:
+         *    1 == Enter debugger
+         *    0 == [the default] detatch debug client
+         *   -1 == Do nothing... and use this until the board resets
+         */
+        switch (kgdbreboot) {
+        case 1:
+                kgdb_breakpoint();
+        case -1:
+                goto done;
+        }
+        if (!dbg_kdb_mode)
+                gdbstub_exit(code);
+done:
+        return NOTIFY_DONE;
+}
+
+static struct notifier_block dbg_reboot_notifier = {
+        .notifier_call          = dbg_notify_reboot,
+        .next                   = NULL,
+        .priority               = INT_MAX,
+};
+
 static void kgdb_register_callbacks(void)
 {
         if (!kgdb_io_module_registered) {
@@ -791,6 +816,7 @@ static void kgdb_register_callbacks(void)
                 kgdb_arch_init();
                 if (!dbg_is_early)
                         kgdb_arch_late();
+                register_reboot_notifier(&dbg_reboot_notifier);
                 atomic_notifier_chain_register(&panic_notifier_list,
                                                &kgdb_panic_event_nb);
 #ifdef CONFIG_MAGIC_SYSRQ
@@ -812,6 +838,7 @@ static void kgdb_unregister_callbacks(void)
          */
         if (kgdb_io_module_registered) {
                 kgdb_io_module_registered = 0;
+                unregister_reboot_notifier(&dbg_reboot_notifier);
                 atomic_notifier_chain_unregister(&panic_notifier_list,
                                                &kgdb_panic_event_nb);
                 kgdb_arch_exit();