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Date:   Fri, 2 Aug 2019 18:50:44 +0200
From:   Adrian Reber <areber@redhat.com>
To:     Christian Brauner <christian@brauner.io>
Cc:     Oleg Nesterov <oleg@redhat.com>,
        Eric Biederman <ebiederm@xmission.com>,
        Pavel Emelianov <xemul@virtuozzo.com>,
        Jann Horn <jannh@google.com>,
        Dmitry Safonov <0x7f454c46@gmail.com>,
        linux-kernel@vger.kernel.org, Andrei Vagin <avagin@gmail.com>,
        Mike Rapoport <rppt@linux.ibm.com>,
        Radostin Stoyanov <rstoyanov1@gmail.com>
Subject: Re: [PATCH v2 1/2] fork: extend clone3() to support CLONE_SET_TID
Message-ID: <20190802165044.GF18263@dcbz.redhat.com>
References: <20190731161223.2928-1-areber@redhat.com>
 <20190731174135.GA30225@redhat.com>
 <20190802072511.GD18263@dcbz.redhat.com>
 <20190802124738.GC20111@redhat.com>
 <20190802132419.GD20111@redhat.com>
 <20190802134611.GF20111@redhat.com>
 <20190802135248.gbtkh5sgjzmbup5h@brauner.io>
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On Fri, Aug 02, 2019 at 03:52:49PM +0200, Christian Brauner wrote:
> On Fri, Aug 02, 2019 at 03:46:11PM +0200, Oleg Nesterov wrote:
> > On 08/02, Oleg Nesterov wrote:
> > >
> > > So Adrian, sorry for confusion, I think your patch is fine.

Good to know.

> > Yes... but do we really need the new CLONE_SET_TID ?
> > 
> > set_tid == 0 has no effect, can't we simply check kargs->set_tid != 0
> > before ns_capable() ?
> 
> Yeah, I agree that sounds much better and aligns with exit_signal.

Let me remove CLONE_SET_TID from the patch and I will try out
idr_is_empty().

I will also address Dmitry's comment about accessing smaller parameter
structs.

		Adrian