linux-kernel - [RFC PATCH 4/8] jump label v4 - notifier atomic call chain notrace

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <5d1c072742086ff48961b0e546c55c4505432daa.1263247114.git.jbaron@redhat.com>
Date:	Tue, 12 Jan 2010 11:26:34 -0500
From:	Jason Baron <jbaron@...hat.com>
To:	linux-kernel@...r.kernel.org
Cc:	mingo@...e.hu, mathieu.desnoyers@...ymtl.ca, hpa@...or.com,
	tglx@...utronix.de, rostedt@...dmis.org, andi@...stfloor.org,
	roland@...hat.com, rth@...hat.com, mhiramat@...hat.com
Subject: [RFC PATCH 4/8] jump label v4 - notifier atomic call chain notrace

notifier atomic call chain notrace

In LTTng, being able to use the atomic notifier from cpu idle entry to
ensure the tracer flush the last events in the current subbuffer
requires the rcu read-side to be marked "notrace", otherwise it can end
up calling back into lockdep and the tracer.

Also apply to the the die notifier.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@...ymtl.ca>
CC: "Paul E. McKenney" <paulmck@...ux.vnet.ibm.com>
CC: Jason Baron <jbaron@...hat.com>
CC: mingo@...e.hu
---
 kernel/notifier.c |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/notifier.c b/kernel/notifier.c
index acd24e7..5bde20a 100644
--- a/kernel/notifier.c
+++ b/kernel/notifier.c
@@ -148,7 +148,7 @@ int atomic_notifier_chain_unregister(struct atomic_notifier_head *nh,
 	spin_lock_irqsave(&nh->lock, flags);
 	ret = notifier_chain_unregister(&nh->head, n);
 	spin_unlock_irqrestore(&nh->lock, flags);
-	synchronize_rcu();
+	synchronize_sched();
 	return ret;
 }
 EXPORT_SYMBOL_GPL(atomic_notifier_chain_unregister);
@@ -178,9 +178,9 @@ int __kprobes __atomic_notifier_call_chain(struct atomic_notifier_head *nh,
 {
 	int ret;
 
-	rcu_read_lock();
+	rcu_read_lock_sched_notrace();
 	ret = notifier_call_chain(&nh->head, val, v, nr_to_call, nr_calls);
-	rcu_read_unlock();
+	rcu_read_unlock_sched_notrace();
 	return ret;
 }
 EXPORT_SYMBOL_GPL(__atomic_notifier_call_chain);
-- 
1.6.5.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/