From mboxrd@z Thu Jan  1 00:00:00 1970
From: Noboru Iwamatsu <n_iwamatsu@jp.fujitsu.com>
Subject: Re: [PATCH] VT-d: improve RMRR validity checking
Date: Fri, 22 Jan 2010 10:35:45 +0900
Message-ID: <4B5900F1.1040105@jp.fujitsu.com>
References: <C77E1D66.6FF7%keir.fraser@eu.citrix.com>
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Hi,

>> I re-send the DRHD-fix patch.
>>
>> If DRHD does not have existent devices, ignore it.
>> If DRHD has both existent and non-existent devices, consider it invalid
>> and not register.
>
> What happens if you register a DRHD with some but not all devices existing?
> Do bad things happen on some systems?

In the case I have posted the log, DRHD has only non-existent devices,
and maybe its info is invalid. So iommu_enable_translation() failed and
became panic.

When DRHD has at least one existent device, I have not seen,
its info might be correct. I cannot judge it, so disabled at the patch.

Even if this DRHD-ignore patch is not accepted, we should validate the
DRHD and stop the PANIC.