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Date: Thu, 20 Nov 2014 12:51:17 -0800
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Subject: Re: frequent lockups in 3.18rc4
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Don Zickus <dzickus@redhat.com>
Cc: Dave Jones <davej@redhat.com>, Andy Lutomirski <luto@amacapital.net>,
        Thomas Gleixner <tglx@linutronix.de>,
        Linux Kernel <linux-kernel@vger.kernel.org>,
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        Peter Zijlstra <peterz@infradead.org>
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On Thu, Nov 20, 2014 at 12:37 PM, Don Zickus <dzickus@redhat.com> wrote:
>
> Just for clarification, softlockups are processes hogging the cpu (thus
> blocking the high priority per-cpu watchdog thread).

Right. And there is no actual sign of any CPU hogging going on.
There's a single system call with a small payload (I think it's safe
to call 64kB small these days), no hugely contended CPU-spinning
locking, nada.

                    Linus