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Date: Mon, 4 Dec 2023 17:12:45 +0100
From: Oleg Nesterov <oleg@redhat.com>
To: Al Viro <viro@zeniv.linux.org.uk>
Cc: NeilBrown <neilb@suse.de>, Christian Brauner <brauner@kernel.org>,
	Jens Axboe <axboe@kernel.dk>, Chuck Lever <chuck.lever@oracle.com>,
	Jeff Layton <jlayton@kernel.org>, Ingo Molnar <mingo@redhat.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Juri Lelli <juri.lelli@redhat.com>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-nfs@vger.kernel.org
Subject: Re: [PATCH 1/2] Allow a kthread to declare that it calls
 task_work_run()
Message-ID: <20231204161245.GA31326@redhat.com>
References: <20231204014042.6754-1-neilb@suse.de>
 <20231204014042.6754-2-neilb@suse.de>
 <20231204024031.GV38156@ZenIV>
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User-Agent: Mutt/1.5.24 (2015-08-30)

I am sick and can't read emails, just one note

On 12/04, Al Viro wrote:
>
> Just have the kernel threads born with ->task_works set to &work_exited

Then irq_thread()->task_work_add() will silently fail,

> and provide a primitive that would flip it from that to NULL.

OK, so this change should update irq_thread(). But what else can fail?

And what if another kthread uses task_work_add(current) to add the
desctructor and does fput() without task_work_run() ?

Oleg.