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Date:   Mon, 27 Jun 2022 00:01:04 +0000
From:   Wedson Almeida Filho <wedsonaf@google.com>
To:     "Eric W. Biederman" <ebiederm@xmission.com>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        Christian Brauner <brauner@kernel.org>,
        Tejun Heo <tj@kernel.org>, Petr Mladek <pmladek@suse.com>,
        Lai Jiangshan <jiangshanlai@gmail.com>,
        Michal Hocko <mhocko@suse.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Oleg Nesterov <oleg@redhat.com>
Subject: Re: re. Spurious wakeup on a newly created kthread
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On Sat, Jun 24, 2022 at 07:19:27PM -0500, Eric W. Biederman wrote:
> 
> Further it is necessary for Peter Zijlstra's rewrite of the kernel
> freezer.   As anything that isn't a special stop state (which
> TASK_UNINTERRUPTIBLE is not) will receive a spurious wake up on when
> thawed out.

Do you know if the current (i.e., prior to the rewrite) kernel freezer
also sends spurious wakeups when thawing tasks?

I'm trying to understand if this source of spurious wakeups will be a
new one or already exists (and might therefore explain what's described
in the original email).