From 3a71f3f3392a92c9a78a0b429c50c66fc589e307 Mon Sep 17 00:00:00 2001 From: Andres Lagar-Cavilla Date: Thu, 26 Jan 2012 13:21:27 +0000 Subject: [PATCH] x86/mm: Avoid spurious deadlock panic trigger In the mm layer, if we take lock A, then lock B, and the recursively lock A, the deadlock detector panics. This is not a deadlock risk because we already 'own' the outer lock (A), so we will not contend for that resource. Signed-off-by: Andres Lagar-Cavilla Acked-by: Tim Deegan Committed-by: Tim Deegan --- xen/arch/x86/mm/mm-locks.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/xen/arch/x86/mm/mm-locks.h b/xen/arch/x86/mm/mm-locks.h index 43dade2b90..9f8413d2b0 100644 --- a/xen/arch/x86/mm/mm-locks.h +++ b/xen/arch/x86/mm/mm-locks.h @@ -61,7 +61,8 @@ do { \ static inline void _mm_lock(mm_lock_t *l, const char *func, int level, int rec) { - __check_lock_level(level); + if ( !((mm_locked_by_me(l)) && rec) ) + __check_lock_level(level); spin_lock_recursive(&l->lock); if ( l->lock.recurse_cnt == 1 ) { -- 2.30.2