From: "Paul E. McKenney" <paulmck@xxxxxxxxxx> [ Upstream commit 8b9b443fa860276822b25057cb3ff3b28734dec0 ] The "pipe_count > RCU_TORTURE_PIPE_LEN" check has a comment saying "Should not happen, but...". This is only true when testing an RCU whose grace periods are always long enough. This commit therefore fixes this comment. Reported-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Closes: https://lore.kernel.org/lkml/CAHk-=wi7rJ-eGq+xaxVfzFEgbL9tdf6Kc8Z89rCpfcQOKm74Tw@xxxxxxxxxxxxxx/ Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx> Signed-off-by: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- kernel/rcu/rcutorture.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index 503c2aa845a4a..2f6c52a863f2e 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -1946,7 +1946,8 @@ static bool rcu_torture_one_read(struct torture_random_state *trsp, long myid) preempt_disable(); pipe_count = READ_ONCE(p->rtort_pipe_count); if (pipe_count > RCU_TORTURE_PIPE_LEN) { - /* Should not happen, but... */ + // Should not happen in a correct RCU implementation, + // happens quite often for torture_type=busted. pipe_count = RCU_TORTURE_PIPE_LEN; } completed = cur_ops->get_gp_seq(); -- 2.43.0