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Date: Thu, 12 Oct 2017 15:13:51 -0700
From: Andi Kleen <ak@linux.intel.com>
To: Borislav Petkov <bp@alien8.de>
Cc: "Luck, Tony" <tony.luck@intel.com>, Jeremy Cline <jcline@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>, x86@kernel.org,
        linux-edac@vger.kernel.org, linux-kernel@vger.kernel.org,
        Laura Abbott <labbott@redhat.com>
Subject: Re: x86/mce: suspicious RCU usage in 4.13.4
Message-ID: <20171012221351.GN5109@tassilo.jf.intel.com>
References: <9840bf0d-6756-75eb-1a2d-d3aace235244@redhat.com>
 <20171010194426.s7keveirclglx6vh@pd.tnic>
 <20171010200841.uhniuwc7pulqgmic@intel.com>
 <871smasqux.fsf@linux.intel.com>
 <20171011115020.i4gkcy5pjifh2zsm@pd.tnic>
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On Thu, Oct 12, 2017 at 11:02:52AM +0200, Borislav Petkov wrote:
> On Wed, Oct 11, 2017 at 04:11:37PM -0700, Andi Kleen wrote:
> > Sorry I take back what I wrote earlier. This RCU is actually still needed,
> > otherwise the reader could see partially written entries.
> 
> Why? All the readers and writers take the mutex now.

Ok fair enough.
-Andi