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From: Nicolai Stange <nicstange@gmail.com>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: Nicolai Stange <nicstange@gmail.com>,
        John Stultz <john.stultz@linaro.org>, linux-kernel@vger.kernel.org
Subject: Re: [RFC v4 14/22] clockevents: clockevents_program_event(): turn clc into unsigned long
References: <20160822233320.4548-1-nicstange@gmail.com>
        <20160822233320.4548-15-nicstange@gmail.com>
        <alpine.DEB.2.20.1608251519080.5714@nanos>
Date: Sat, 27 Aug 2016 17:23:18 +0200
In-Reply-To: <alpine.DEB.2.20.1608251519080.5714@nanos> (Thomas Gleixner's
        message of "Thu, 25 Aug 2016 15:20:59 +0200 (CEST)")
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Thomas Gleixner <tglx@linutronix.de> writes:

> On Tue, 23 Aug 2016, Nicolai Stange wrote:
>
>> Right now, being of type unsigned long long, the clc local variable in
>> clockevents_program_event() is unnecessarily wide as it gets cast to
>> unsigned long anyway.
>
> Congrats! You just broke 32bit systems. When delta is sufficiently large then
> the mult overflows....

The 32bit breakage has been introduced in [13/22] ("clockevents: check a
programmed delta's bounds in terms of cycles") already -- please see my
reply there.