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From:   Yuyang Du <duyuyang@gmail.com>
To:     peterz@infradead.org, will.deacon@arm.com, mingo@kernel.org
Cc:     bvanassche@acm.org, ming.lei@redhat.com,
        linux-kernel@vger.kernel.org, joe@perches.com,
        Yuyang Du <duyuyang@gmail.com>
Subject: [PATCH v3 11/18] locking/lockdep: Update comment
Date:   Thu, 21 Mar 2019 15:57:18 +0800
Message-Id: <20190321075725.14054-12-duyuyang@gmail.com>
In-Reply-To: <20190321075725.14054-1-duyuyang@gmail.com>
References: <20190321075725.14054-1-duyuyang@gmail.com>
Sender: linux-kernel-owner@vger.kernel.org
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An out-of-nowhere comment is removed. While at it, add more explanatory
comments. Such a trivial patch!

Signed-off-by: Yuyang Du <duyuyang@gmail.com>
---
 kernel/locking/lockdep.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index c7aec9f..eccfb0b 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -2720,10 +2720,16 @@ static int validate_chain(struct task_struct *curr,
 		 * - is softirq-safe, if this lock is hardirq-unsafe
 		 *
 		 * And check whether the new lock's dependency graph
-		 * could lead back to the previous lock.
+		 * could lead back to the previous lock:
 		 *
-		 * any of these scenarios could lead to a deadlock. If
-		 * All validations
+		 * - within the current held-lock stack
+		 * - across our accumulated lock dependency records
+		 *
+		 * any of these scenarios could lead to a deadlock.
+		 */
+		/*
+		 * The simple case: does the current hold the same lock
+		 * already?
 		 */
 		int ret = check_deadlock(curr, hlock, hlock->read);
 
-- 
1.8.3.1