From: Frederic Weisbecker <frederic@kernel.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: LKML <linux-kernel@vger.kernel.org>,
Frederic Weisbecker <frederic@kernel.org>,
"Paul E . McKenney" <paulmck@kernel.org>,
Thomas Gleixner <tglx@linutronix.de>,
Phil Auld <pauld@redhat.com>,
Marcelo Tosatti <mtosatti@redhat.com>
Subject: [PATCH 3/5] sched: Detect call to schedule from critical entry code
Date: Tue, 17 Nov 2020 16:16:35 +0100 [thread overview]
Message-ID: <20201117151637.259084-4-frederic@kernel.org> (raw)
In-Reply-To: <20201117151637.259084-1-frederic@kernel.org>
Detect calls to schedule() between user_enter() and user_exit(). Those
are symptoms of early entry code that either forgot to protect a call
to schedule() inside exception_enter()/exception_exit() or, in the case
of HAVE_CONTEXT_TRACKING_OFFSTACK, enabled interrupts or preemption in
a wrong spot.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Phil Auld <pauld@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
---
kernel/sched/core.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index d2003a7d5ab5..c23d7cb5aee3 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -4291,6 +4291,7 @@ static inline void schedule_debug(struct task_struct *prev, bool preempt)
preempt_count_set(PREEMPT_DISABLED);
}
rcu_sleep_check();
+ SCHED_WARN_ON(ct_state() == CONTEXT_USER);
profile_hit(SCHED_PROFILING, __builtin_return_address(0));
--
2.25.1
next prev parent reply other threads:[~2020-11-17 15:17 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-17 15:16 [PATCH 0/5] context_tracking: Flatter archs not using exception_enter/exit() v3 Frederic Weisbecker
2020-11-17 15:16 ` [PATCH 1/5] context_tracking: Introduce HAVE_CONTEXT_TRACKING_OFFSTACK Frederic Weisbecker
2020-11-20 12:44 ` [tip: core/entry] " tip-bot2 for Frederic Weisbecker
2020-11-17 15:16 ` [PATCH 2/5] context_tracking: Don't implement exception_enter/exit() on CONFIG_HAVE_CONTEXT_TRACKING_OFFSTACK Frederic Weisbecker
2020-11-20 12:44 ` [tip: core/entry] " tip-bot2 for Frederic Weisbecker
2020-11-17 15:16 ` Frederic Weisbecker [this message]
2020-11-20 12:44 ` [tip: core/entry] sched: Detect call to schedule from critical entry code tip-bot2 for Frederic Weisbecker
2020-11-17 15:16 ` [PATCH 4/5] context_tracking: Only define schedule_user() on !HAVE_CONTEXT_TRACKING_OFFSTACK archs Frederic Weisbecker
2020-11-20 12:44 ` [tip: core/entry] " tip-bot2 for Frederic Weisbecker
2020-11-17 15:16 ` [PATCH 5/5] x86: Support HAVE_CONTEXT_TRACKING_OFFSTACK Frederic Weisbecker
2020-11-20 12:44 ` [tip: core/entry] " tip-bot2 for Frederic Weisbecker
2020-11-18 7:39 ` [PATCH 0/5] context_tracking: Flatter archs not using exception_enter/exit() v3 Peter Zijlstra
2020-11-18 13:48 ` Frederic Weisbecker
2020-11-18 14:05 ` Peter Zijlstra
2020-11-18 14:20 ` Frederic Weisbecker
-- strict thread matches above, loose matches on Subject: below --
2020-10-27 15:08 [PATCH 0/5] context_tracking: Flatter archs not using exception_enter/exit() v2 Frederic Weisbecker
2020-10-27 15:08 ` [PATCH 3/5] sched: Detect call to schedule from critical entry code Frederic Weisbecker
2020-10-05 10:49 [PATCH 0/5] context_tracking: Flatter archs not using exception_enter/exit() Frederic Weisbecker
2020-10-05 10:49 ` [PATCH 3/5] sched: Detect call to schedule from critical entry code Frederic Weisbecker
2020-10-05 11:23 ` Peter Zijlstra
2020-10-05 12:26 ` Frederic Weisbecker
2020-10-07 9:34 ` Mel Gorman
2020-10-26 14:37 ` Frederic Weisbecker
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