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Date: Sat, 11 Feb 2017 21:36:21 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Ard Biesheuvel <ard.biesheuvel@linaro.org>
cc: Bhumika Goyal <bhumirks@gmail.com>,
        Julia Lawall <julia.lawall@lip6.fr>,
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        <linux-arm-kernel@lists.infradead.org>,
        Kees Cook <keescook@chromium.org>
Subject: Re: [PATCH] clocksource: add __ro_after_init to cyclecounter
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On Sat, 11 Feb 2017, Ard Biesheuvel wrote:

> On 11 February 2017 at 19:20, Bhumika Goyal <bhumirks@gmail.com> wrote:
> > The object cyclecounter of type cyclecounter is not getting modified
> > after getting initialized by arch_counter_register. Apart from
> > initialization in arch_counter_register it is also passed as an argument
> > to the function timecounter_init but this argument is of type const.
> > Therefore, add __ro_after_init to its declaration.
> >
> 
> I think adding __ro_after_init is fine if this struct is never
> modified after init. But the reference in the commit log to the
> constness of the timecounter_init() argument  makes no sense: that
> only means timecounter_init() will not modify the object, which allows
> pointers to const objects to be passed to it as well. The opposite is
> not true, though: there is no requirement whatsoever that objects
> passed into const pointer arguments should be const themselves.

Indeed.