From: Tim Deegan <tim@xen.org>
Date: Wed, 18 Apr 2012 15:43:13 +0000 (+0100)
Subject: x86/mm: BUG() rather than panic() on mm lock order violations
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=4784ab249a6a8f588cf5b7e467d4d486c5009e9f;p=xen.git

x86/mm: BUG() rather than panic() on mm lock order violations

That gives us a backtrace showing where the bad lock happens.

Reported-by: Andres Lagar-Cavilla <andres@lagarcavilla.org
Signed-off-by: Tim Deegan <tim@xen.org>
Acked-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Committed-by: Tim Deegan <tim@xen.org>
---

diff --git a/xen/arch/x86/mm/mm-locks.h b/xen/arch/x86/mm/mm-locks.h
index c973b4672b..8f5c7f5a14 100644
--- a/xen/arch/x86/mm/mm-locks.h
+++ b/xen/arch/x86/mm/mm-locks.h
@@ -50,8 +50,11 @@ static inline int mm_locked_by_me(mm_lock_t *l)
 #define __check_lock_level(l)                           \
 do {                                                    \
     if ( unlikely(__get_lock_level()) > (l) )           \
-        panic("mm locking order violation: %i > %i\n",  \
-              __get_lock_level(), (l));                 \
+    {                                                   \
+        printk("mm locking order violation: %i > %i\n", \
+               __get_lock_level(), (l));                \
+        BUG();                                          \
+    }                                                   \
 } while(0)
 
 #define __set_lock_level(l)         \