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Date: Sun, 11 Jan 2015 13:41:46 +0100
From: Richard Cochran <richardcochran@gmail.com>
To: John Stultz <john.stultz@linaro.org>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Dave Jones <davej@codemonkey.org.uk>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Prarit Bhargava <prarit@redhat.com>,
        Stephen Boyd <sboyd@codeaurora.org>, Ingo Molnar <mingo@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH 06/10] time: Cap clocksource reads to the clocksource
 max_cycles value
Message-ID: <20150111124146.GA15387@localhost.localdomain>
References: <1420850068-27828-1-git-send-email-john.stultz@linaro.org>
 <1420850068-27828-7-git-send-email-john.stultz@linaro.org>
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On Fri, Jan 09, 2015 at 04:34:24PM -0800, John Stultz wrote:
> When calculating the current delta since the last tick, we
> currently have no hard protections to prevent a multiplciation
> overflow from ocurring.

This is just papering over the problem. The "hard protection" should
be having a tick scheduled before the range of the clock source is
exhausted.

Thanks,
Richard