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Subject: Re: tip -ENOBOOT - bisected to locking/refcounts, x86/asm:
 Implement fast refcount overflow protection
From: Mike Galbraith <efault@gmx.de>
To: Kees Cook <keescook@chromium.org>
Cc: "David S. Miller" <davem@davemloft.net>,
        Peter Zijlstra <peterz@infradead.org>,
        LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>,
        "Reshetova, Elena" <elena.reshetova@intel.com>,
        Network Development <netdev@vger.kernel.org>
Date: Thu, 31 Aug 2017 19:19:27 +0200
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On Thu, 2017-08-31 at 10:00 -0700, Kees Cook wrote:
> 
> Oh! So it's gcc-version sensitive? That's alarming. Is this mapping correct:
> 
> 4.8.5: WARN, eventual kernel hang
> 6.3.1, 7.0.1: WARN, but continues working

Yeah, that's correct.  I find that troubling, simply because this gcc
version has been through one hell of a lot of kernels with me.  Yeah, I
know, that doesn't exempt it from having bugs, but color me suspicious.

	-Mike