From: Thomas Gleixner <tglx@linutronix.de>
To: Miroslav Lichvar <mlichvar@redhat.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
John Stultz <john.stultz@linaro.org>,
Stephen Boyd <sboyd@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
Richard Cochran <richardcochran@gmail.com>,
Hongbo Yao <yaohongbo@huawei.com>,
Xiongfeng Wang <wangxiongfeng2@huawei.com>,
Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH] timekeeping: Force upper bound for setting CLOCK_REALTIME
Date: Tue, 26 Mar 2019 13:31:16 +0100 (CET) [thread overview]
Message-ID: <alpine.DEB.2.21.1903261329040.1789@nanos.tec.linutronix.de> (raw)
In-Reply-To: <20190326092607.GE14186@localhost>
On Tue, 26 Mar 2019, Miroslav Lichvar wrote:
> On Sat, Mar 23, 2019 at 11:36:19AM +0100, Thomas Gleixner wrote:
> > It is reasonable to force an upper bound for the various methods of setting
> > CLOCK_REALTIME. Year 2262 is the absolute upper bound. Assume a maximum
> > uptime of 30 years which is plenty enough even for esoteric embedded
> > systems. That results in an upper bound of year 2232 for setting the time.
>
> The patch looks good to me.
>
> I like this approach better than using a larger value closer to the
> overflow (e.g. one week) and stepping the clock back automatically
> when the clock reaches that time, but I suspect it might possibly
> break more tests (or any unusual applications messing with time) as a
> much larger interval is now EINVAL.
I'm fine with breaking a few tests on the way rather than having undefined
behaviour and the constant flow of patches tackling the wrong end of the
stick.
Thanks,
tglx
next prev parent reply other threads:[~2019-03-26 12:31 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-23 10:36 [PATCH] timekeeping: Force upper bound for setting CLOCK_REALTIME Thomas Gleixner
2019-03-26 9:26 ` Miroslav Lichvar
2019-03-26 12:31 ` Thomas Gleixner [this message]
2019-03-26 13:16 ` Arnd Bergmann
2019-03-26 23:00 ` Thomas Gleixner
2019-03-28 12:46 ` [tip:timers/core] " tip-bot for Thomas Gleixner
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