Date: Wed, 4 Nov 2015 14:43:46 -0500
From: Tejun Heo <tj@kernel.org>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: Chris Worley <chris.worley@primarydata.com>, linux-kernel@vger.kernel.org,
        bfields@fieldses.org,
        Michael Skralivetsky <michael.skralivetsky@primarydata.com>,
        Trond Myklebust <trond.myklebust@primarydata.com>,
        Shaohua Li <shli@fb.com>, Jeff Layton <jlayton@poochiereds.net>,
        kernel-team@fb.com
Subject: Re: [PATCH] timer: add_timer_on() should perform proper migration
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Hello, Thomas.

On Wed, Nov 04, 2015 at 08:35:00PM +0100, Thomas Gleixner wrote:
> nice detective work. This has been there forever. I really wonder why
> nobody ever triggered this before.

I guess there weren't enough concurrent del/add_timer_on() combos.
Workqueue recently switched to always use add_timer_on() from its
timer function making that a lot more frequent for heavy
mod_delayed_work_on() users and that's when it started surfacing.

Thanks.

-- 
tejun
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