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Date: Tue, 16 Feb 2016 11:08:01 -0500
From: Tejun Heo <tj@kernel.org>
To: Petr Mladek <pmladek@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, Oleg Nesterov <oleg@redhat.com>,
        Ingo Molnar <mingo@redhat.com>, Peter Zijlstra <peterz@infradead.org>,
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        Josh Triplett <josh@joshtriplett.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Jiri Kosina <jkosina@suse.cz>, Borislav Petkov <bp@suse.de>,
        Michal Hocko <mhocko@suse.cz>, linux-mm@kvack.org,
        Vlastimil Babka <vbabka@suse.cz>, linux-api@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v4 04/22] kthread: Add create_kthread_worker*()
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Hello,

On Tue, Feb 16, 2016 at 04:44:43PM +0100, Petr Mladek wrote:
> I wanted to be sure. The cpu number is later passed to
> cpu_to_node(cpu) in kthread_create_on_cpu().
> 
> I am going to replace this with a check against nr_cpu_ids in
> kthread_create_on_cpu() which makes more sense.
> 
> I might be too paranoid. But this is slow path. People
> do mistakes...

idk, that just ended up adding a subtly broken code which checks for
an unlikely condition which would cause a crash anyway.  I don't see
the point.  If you want to insist on it, please at least make it a
WARN_ON().  It's a clear kernel bug.

Thanks.

-- 
tejun