From: Stefan Wiehler <stefan.wiehler@nokia.com>
To: Boqun Feng <boqun.feng@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>,
"Paul E. McKenney" <paulmck@kernel.org>,
Joel Fernandes <joel@joelfernandes.org>,
Josh Triplett <josh@joshtriplett.org>,
Steven Rostedt <rostedt@goodmis.org>,
Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
Lai Jiangshan <jiangshanlai@gmail.com>,
Zqiang <qiang.zhang1211@gmail.com>,
linux-arm-kernel@lists.infradead.org, rcu@vger.kernel.org,
linux-kernel@vger.kernel.org,
Frederic Weisbecker <frederic@kernel.org>
Subject: Re: [PATCH] arm: smp: Avoid false positive CPU hotplug Lockdep-RCU splat
Date: Fri, 8 Mar 2024 11:20:58 +0100 [thread overview]
Message-ID: <c567c622-1ee1-4828-8730-62bf6bfc2ecc@nokia.com> (raw)
In-Reply-To: <ZeoMRfy9ISBOVMsV@boqun-archlinux>
> I'm not sure this is a false-positive: if you traverse an RCU-list
> without RCU watching the CPU, then a grace period may pass, the next
> list can be garbage and you can go anywhere from the list. Or am I
> missing something that a CPU hotplug can block a grace period?
Thanks for the feedback! Yes, calling it a false positive is probably not
correct, I will remove that. However, as Russell has explained in a previous
email, the spinlock is fundamental for ASID handling and cannot be removed.
@Russell, I will submit to the patch tracking system then.
next prev parent reply other threads:[~2024-03-08 10:21 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-03-07 16:09 Stefan Wiehler
2024-03-07 17:45 ` Paul E. McKenney
2024-03-07 17:49 ` Paul E. McKenney
2024-03-07 18:54 ` Russell King (Oracle)
2024-03-07 19:08 ` Paul E. McKenney
2024-03-07 18:49 ` Boqun Feng
2024-03-08 10:20 ` Stefan Wiehler [this message]
2024-03-08 14:57 ` Joel Fernandes
2024-03-09 7:45 ` Stefan Wiehler
2024-03-09 9:57 ` Russell King (Oracle)
2024-03-12 22:14 ` Will Deacon
2024-03-12 22:39 ` Russell King (Oracle)
2024-03-13 0:32 ` Will Deacon
2024-03-13 9:58 ` Russell King (Oracle)
2024-08-09 13:37 ` Stefan Wiehler
2024-08-09 13:48 ` Russell King (Oracle)
2024-08-09 14:06 ` Stefan Wiehler
2024-03-11 16:08 ` Russell King (Oracle)
2024-03-11 16:17 ` Stefan Wiehler
2024-03-11 19:01 ` Paul E. McKenney
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