From mboxrd@z Thu Jan  1 00:00:00 1970
From: Linas Vepstas <linas@austin.ibm.com>
Date: Tue, 12 Jul 2005 21:14:01 +0000
Subject: Re: [PATCH 2.6.13-rc1 07/10] IOCHK interface for I/O error handling/detecting
Message-Id: <20050712211401.GF26607@austin.ibm.com>
List-Id: <linux-ia64.vger.kernel.org>
References: <42CB63B2.6000505@jp.fujitsu.com> <42CB6961.2060508@jp.fujitsu.com>
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To: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Linux Kernel list <linux-kernel@vger.kernel.org>, linux-ia64@vger.kernel.org, "Luck, Tony" <tony.luck@intel.com>, Benjamin Herrenschmidt <benh@kernel.crashing.org>, long <tlnguyen@snoqualmie.dp.intel.com>, linux-pci@atrey.karlin.mff.cuni.cz, linuxppc64-dev <linuxppc64-dev@ozlabs.org>

On Wed, Jul 06, 2005 at 02:17:21PM +0900, Hidetoshi Seto was heard to remark:
> 
> Touching poisoned data become a MCA, so now it directly means

Several questions: 

Is MCA an exception or fault of some sort, so at some point, 
the kernel would catch a fault?

So when you say "Touching poisoned data become a MCA", you mean that
if the CPU attempts to read poisoned data through the pci-to-host
bridge, it will (at some point) catch an exception?

> +	ia64_mca_barrier(ret);

I assume that the point of this barrier is to make sure that the fault,
if any, is delivered before this routine returns?

--linas