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: <20210106165231.20441-1-paulmck@kernel.org>
Date:   Wed,  6 Jan 2021 08:52:28 -0800
From:   paulmck@...nel.org
To:     rcu@...r.kernel.org
Cc:     linux-kernel@...r.kernel.org, kernel-team@...com, mingo@...nel.org,
        jiangshanlai@...il.com, akpm@...ux-foundation.org,
        mathieu.desnoyers@...icios.com, josh@...htriplett.org,
        tglx@...utronix.de, peterz@...radead.org, rostedt@...dmis.org,
        dhowells@...hat.com, edumazet@...gle.com, fweisbec@...il.com,
        oleg@...hat.com, joel@...lfernandes.org,
        "Paul E. McKenney" <paulmck@...nel.org>
Subject: [PATCH tip/core/rcu 1/4] rcu: Mark obtuse portion of stall warning as internal debug

From: "Paul E. McKenney" <paulmck@...nel.org>

There is a rather obtuse string that can be printed as part of an
expedited RCU CPU stall-warning message that starts with "blocking
rcu_node structures".  Under normal conditions, most of this message
is just repeating the list of CPUs blocking the current expedited grace
period, but in a manner that is rather difficult to read.  This commit
therefore marks this message as "(internal RCU debug)" in an effort to
give people the option of avoiding wasting time attempting to extract
nonexistent additional meaning from this portion of the message.

Reported-by: Jonathan Lemon <bsd@...com>
Signed-off-by: Paul E. McKenney <paulmck@...nel.org>
---
 kernel/rcu/tree_exp.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/rcu/tree_exp.h b/kernel/rcu/tree_exp.h
index 8760b6e..6c6ff06 100644
--- a/kernel/rcu/tree_exp.h
+++ b/kernel/rcu/tree_exp.h
@@ -545,7 +545,7 @@ static void synchronize_rcu_expedited_wait(void)
 			data_race(rnp_root->expmask),
 			".T"[!!data_race(rnp_root->exp_tasks)]);
 		if (ndetected) {
-			pr_err("blocking rcu_node structures:");
+			pr_err("blocking rcu_node structures (internal RCU debug):");
 			rcu_for_each_node_breadth_first(rnp) {
 				if (rnp == rnp_root)
 					continue; /* printed unconditionally */
-- 
2.9.5

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ