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From:   Arnd Bergmann <arnd@arndb.de>
Date:   Wed, 20 Jun 2018 09:39:21 +0200
Message-ID: <CAK8P3a2CVxTioR0s9xX3T_q+wR6mxHXTyw1U5vWaPeabNQrR0Q@mail.gmail.com>
Subject: Re: [Ocfs2-devel] [PATCH] ocfs2: dlmglue: clean up timestamp handling
To:     Goldwyn Rodrigues <rgoldwyn@suse.de>
Cc:     Mark Fasheh <mark@fasheh.com>, Joel Becker <jlbec@evilplan.org>,
        y2038 Mailman List <y2038@lists.linaro.org>,
        Eric Ren <zren@suse.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Deepa Dinamani <deepa.kernel@gmail.com>,
        ocfs2-devel@oss.oracle.com
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On Tue, Jun 19, 2018 at 11:52 PM, Goldwyn Rodrigues <rgoldwyn@suse.de> wrote:
> On 06-19 21:11, Arnd Bergmann wrote:
>> On Tue, Jun 19, 2018 at 7:14 PM, Goldwyn Rodrigues <rgoldwyn@suse.de> wrote:
>> > On 06-19 17:58, Arnd Bergmann wrote:

>> Here, setting a timestamp before 1970 or after 2514 will get wrapped
>> around in unpatched kernels, but will be clamped to the minimum
>> and maximum times after the patch.
>>
>> It is extremely rare for correct code to need timestamps outside of that
>> range, but it is also trivial to trigger that with a manual 'touch' command
>> from user space.
>>
>> If the change is a problem, I can resend the patch without that one
>> line change.
>>
>
> I think you should keep the change, but incrment OCFS2_LVB_VERSION.

Won't that cause additional incompatibilities? I don't know how this
macro gets used, but normally we don't use version numbers in
kernel interfaces if that prevents us from using old user space code
with newer kernels.

      Arnd