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Date: Mon, 11 Aug 2014 04:49:40 -0700 (PDT)
From: David Rientjes <rientjes@google.com>
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To: Manuel Lauss <manuel.lauss@gmail.com>
cc: Kees Cook <keescook@chromium.org>, Linux-MIPS <linux-mips@linux-mips.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: MIPS: hang in kmalloc with seccomp writer locks
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On Mon, 11 Aug 2014, Manuel Lauss wrote:

> Hi Kees,
> 
> My MIPS32 toys hang early during bootup at the first kmalloc() with
> seccomp enabled.
> I've bisected it to commit dbd952127d11bb44a4ea30b08cc60531b6a23d71
> ("seccomp: introduce writer locking").  And indeed, reverting this
> commit fixes the hang.
> 
> I'm not sure if seccomp is even working on MIPS, but I've never had
> problems with
> it before so I thought I let you know.
> 

Does enabling CONFIG_DEBUG_SPINLOCK fix the issue?