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From:   "Liam R. Howlett" <Liam.Howlett@oracle.com>
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     maple-tree@lists.infradead.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org,
        "Liam R. Howlett" <Liam.Howlett@Oracle.com>,
        "Liam R . Howlett" <Liam.Howlett@oracle.com>
Subject: [PATCH v4 08/35] maple_tree: Change RCU checks to WARN_ON() instead of BUG_ON()
Date:   Thu, 18 May 2023 10:55:17 -0400
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From: "Liam R. Howlett" <Liam.Howlett@Oracle.com>

If RCU is enabled and the tree isn't locked, just warn the user and
avoid crashing the kernel.

Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
---
 include/linux/maple_tree.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/linux/maple_tree.h b/include/linux/maple_tree.h
index 204d7941a39e..ed92abf4c1fb 100644
--- a/include/linux/maple_tree.h
+++ b/include/linux/maple_tree.h
@@ -616,7 +616,7 @@ static inline void mt_clear_in_rcu(struct maple_tree *mt)
 		return;
 
 	if (mt_external_lock(mt)) {
-		BUG_ON(!mt_lock_is_held(mt));
+		WARN_ON(!mt_lock_is_held(mt));
 		mt->ma_flags &= ~MT_FLAGS_USE_RCU;
 	} else {
 		mtree_lock(mt);
@@ -635,7 +635,7 @@ static inline void mt_set_in_rcu(struct maple_tree *mt)
 		return;
 
 	if (mt_external_lock(mt)) {
-		BUG_ON(!mt_lock_is_held(mt));
+		WARN_ON(!mt_lock_is_held(mt));
 		mt->ma_flags |= MT_FLAGS_USE_RCU;
 	} else {
 		mtree_lock(mt);
-- 
2.39.2