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Date:   Fri, 8 Apr 2022 20:49:25 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>, jstultz@google.com,
        Stephen Boyd <sboyd@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Marcel Holtmann <marcel@holtmann.org>,
        Johan Hedberg <johan.hedberg@gmail.com>,
        Luiz Augusto von Dentz <luiz.dentz@gmail.com>,
        Eric Dumazet <edumazet@google.com>,
        Guenter Roeck <linux@roeck-us.net>
Subject: Re: [RFC][PATCH] timers: Add del_time_free() to be called before
 freeing timers
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On Fri, 8 Apr 2022 14:30:21 -1000
Linus Torvalds <torvalds@linux-foundation.org> wrote:

> On Fri, Apr 8, 2022 at 2:22 PM Steven Rostedt <rostedt@goodmis.org> wrote:
> >
> > We could always use the LSB bit of the function as a "shutdown" flag, where:  
> 
> While we do that for data pointers, doing it for function pointers is dodgy.
> 
> Not all architectures necessarily align code pointers. In fact, I
> think that "-Os" on x86 makes all code alignment go away, and so
> function pointers have no alignment at all.

Hmm, well, I'm not sure it would work for all architectures, but what
about the MSB?  Setting it to zero on "shutdown"?

-- Steve