From: Thomas Gleixner <tglx@linutronix.de>
To: Lukasz Majewski <lukma@denx.de>, Andrei Vagin <avagin@gmail.com>,
Dmitry Safonov <dima@arista.com>
Cc: GNU C Library <libc-alpha@sourceware.org>,
Arnd Bergmann <arnd@arndb.de>,
linux-kernel@vger.kernel.org
Subject: Re: [Y2038][time namespaces] Question regarding CLOCK_REALTIME support plans in Linux time namespaces
Date: Fri, 30 Oct 2020 14:08:48 +0100 [thread overview]
Message-ID: <871rhfoo7z.fsf@nanos.tec.linutronix.de> (raw)
In-Reply-To: <20201030110229.43f0773b@jawa>
Lukasz,
On Fri, Oct 30 2020 at 11:02, Lukasz Majewski wrote:
> I do have a question regarding the Linux time namespaces in respect of
> adding support for virtualizing the CLOCK_REALTIME.
>
> According to patch description [1] and time_namespaces documentation
> [2] the CLOCK_REALTIME is not supported (for now?) to avoid complexity
> and overhead in the kernel.
>
> Is there any plan to add support for it in a near future?
Not really. Just having an offset on clock realtime would be incorrect
in a number of ways. Doing it correct is a massive trainwreck.
For a debug aid, which is what you are looking for, the correctness
would not really matter, but providing that is a really slippery
slope.
If at all we could hide it under a debug option which depends on
CONFIG_BROKEN and emitting a big fat warning in dmesg with a clear
statement that it _is_ broken, stays so forever and any attempt to "fix"
it results in a permanent ban from all kernel lists.
Preferrably we don't go there.
Thanks,
tglx
next prev parent reply other threads:[~2020-10-30 13:08 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-30 10:02 [Y2038][time namespaces] Question regarding CLOCK_REALTIME support plans in Linux time namespaces Lukasz Majewski
2020-10-30 13:08 ` Thomas Gleixner [this message]
2020-10-30 15:43 ` Lukasz Majewski
2020-10-30 13:58 ` Cyril Hrubis
2020-10-30 14:02 ` Zack Weinberg
2020-10-30 15:10 ` Thomas Gleixner
2020-10-30 16:58 ` Carlos O'Donell
2020-10-30 20:06 ` Thomas Gleixner
2020-10-30 22:19 ` Carlos O'Donell
2020-10-31 1:38 ` Thomas Gleixner
2020-11-03 12:43 ` Cyril Hrubis
2020-11-05 17:25 ` Carlos O'Donell
2020-11-07 0:47 ` Thomas Gleixner
2020-11-19 18:37 ` Carlos O'Donell
2020-11-20 0:14 ` Thomas Gleixner
2020-11-25 17:06 ` Petr Špaček
2020-11-25 20:37 ` Carlos O'Donell
2020-11-26 0:17 ` Thomas Gleixner
2020-11-26 3:05 ` Carlos O'Donell
2020-11-26 8:21 ` Andreas Schwab
2020-11-14 10:25 ` Pavel Machek
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