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Date: Fri, 28 Oct 2016 20:44:27 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Oleg Nesterov <oleg@redhat.com>
cc: Andy Lutomirski <luto@amacapital.net>,
        Roman Pen <roman.penyaev@profitbricks.com>,
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        Tejun Heo <tj@kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 0/2] kthread: make struct kthread kmalloc'ed
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On Fri, 28 Oct 2016, Oleg Nesterov wrote:
> On 10/26, Thomas Gleixner wrote:
> 
> > Be careful with anonymous unions. There are a few pitfalls with older
> > compilers. That's why I said make it a proper union and fixup the 5 usage
> > sites.
> 
> Ah. Then I'd prefer to do this later or in a separate change, unless you
> feel strongly. I certainly do not want to update other users at least right
> now.
> 
> Yes, these 2 type casts do not look nice, but they are hidden in the trivial
> helpers. And, for example, if something goes wrong we can trivially change
> this code to use, say, sas_ss_sp. Just we need to update the comments to
> explain why it is safe too.
> 
> Finally. I still hope we will kill struct kthread (I mean, unbloat it and
> embed into task_struct), and this means that the proper union should touch
> more members. Say, sas_* and/or vfork_done+set/clear_child_tid. I'd like
> to do this only once if possible.

Fair enough.

Thanks,

	tglx