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Date:   Wed, 18 Mar 2020 12:57:31 +0100
From:   Christian Brauner <christian.brauner@ubuntu.com>
To:     Cyrill Gorcunov <gorcunov@gmail.com>
Cc:     Adrian Reber <areber@redhat.com>,
        Eric Biederman <ebiederm@xmission.com>,
        Pavel Emelyanov <ovzxemul@gmail.com>,
        Oleg Nesterov <oleg@redhat.com>,
        Dmitry Safonov <0x7f454c46@gmail.com>,
        Andrei Vagin <avagin@gmail.com>, linux-kernel@vger.kernel.org,
        Mike Rapoport <rppt@linux.ibm.com>,
        Radostin Stoyanov <rstoyanov1@gmail.com>,
        Michael Kerrisk <mtk.manpages@gmail.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH 1/4] ns: prepare time namespace for clone3()
Message-ID: <20200318115731.3vn7cjchunk2bqoe@wittgenstein>
References: <20200317083043.226593-1-areber@redhat.com>
 <20200317083043.226593-2-areber@redhat.com>
 <20200318105747.GP27301@uranus>
 <20200318111726.u2r3ghymexyng5nn@wittgenstein>
 <20200318112814.GQ27301@uranus>
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On Wed, Mar 18, 2020 at 02:28:14PM +0300, Cyrill Gorcunov wrote:
> On Wed, Mar 18, 2020 at 12:17:26PM +0100, Christian Brauner wrote:
> > On Wed, Mar 18, 2020 at 01:57:47PM +0300, Cyrill Gorcunov wrote:
> > > On Tue, Mar 17, 2020 at 09:30:41AM +0100, Adrian Reber wrote:
> > > ...
> > > > +/*
> > > > + * This structure is used to set the time namespace offset
> > > > + * via /proc as well as via clone3().
> > > > + */
> > > > +struct set_timens_offset {
> > > > +	int			clockid;
> > > > +	struct timespec64	val;
> > > > +};
> > > > +
> > > 
> > > I'm sorry, I didn't follow this series much so can't comment right now.
> > > Still this structure made me a bit wonder -- the @val seems to be 8 byte
> > > aligned and I guess we have a useless pad between these members. If so
> > > can we swap them? Or it is already part of api?
> > 
> > It's not part of the api yet. We're still arguing about how and what we
> > want to pass down.
> 
> I see, thanks for info! So I think we could swap the members.

Yeah, _if_ we go with a version of this struct we definitely need to
ensure proper padding/alignment!