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Subject: Re: regression since 4.8 and newer in select_idle_siblings()
From: Mike Galbraith <efault@gmx.de>
To: Igor Mammedov <imammedo@redhat.com>, linux-kernel@vger.kernel.org
Cc: mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de,
        torvalds@linux-foundation.org
Date: Tue, 18 Oct 2016 16:02:07 +0200
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On Tue, 2016-10-18 at 15:40 +0200, Igor Mammedov wrote:
> kernel crashes at runtime  due null pointer dereference at
>   select_idle_sibling()
>      -> select_idle_cpu()
>          ...
>          u64 avg_cost = this_sd->avg_scan_cost;
> 
> regression bisects to:
>   commit 10e2f1acd0106c05229f94c70a344ce3a2c8008b
>   Author: Peter Zijlstra <peterz@infradead.org>
>   sched/core: Rewrite and improve select_idle_siblings()

http://git.kernel.org/tip/9cfb38a7ba5a9c27c1af8093fb1af4b699c0a441

Already fixed, and will land in Linus' tree soon.

	-Mike