[PATCH] avoid resursive oopses

Prevent recursive faults in do_exit() by leaving the task alone and wait
for reboot.  This may allow a more graceful shutdown and possibly save the
original oops.

Signed-off-by: Alexander Nyberg <alexn@telia.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/kernel/exit.c b/kernel/exit.c
index 2ef2ad54020177cd355174b8d4a52656edebd6d2..c2bdf6fb61a57e10855e2d6092a0d3473438d8c3 100644 (file)
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -793,6 +793,17 @@ fastcall NORET_TYPE void do_exit(long code)
                ptrace_notify((PTRACE_EVENT_EXIT << 8) | SIGTRAP);
        }
 
+       /*
+        * We're taking recursive faults here in do_exit. Safest is to just
+        * leave this task alone and wait for reboot.
+        */
+       if (unlikely(tsk->flags & PF_EXITING)) {
+               printk(KERN_ALERT
+                       "Fixing recursive fault but reboot is needed!\n");
+               set_current_state(TASK_UNINTERRUPTIBLE);
+               schedule();
+       }
+
        tsk->flags |= PF_EXITING;
 
        /*