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Subject: Re: [PATCH 1/6] powerpc/eeh: Don't collect PCI-CFG data on PHB
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Gavin Shan <shangw@linux.vnet.ibm.com>
Date: Tue, 25 Jun 2013 21:55:15 +1000
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On Tue, 2013-06-25 at 18:00 +0800, Gavin Shan wrote:
> +       /*
> +        * When the PHB is fenced or dead, it's pointless to collect
> +        * the data from PCI config space because it should return
> +        * 0xFF's. For ER, we still retrieve the data from the PCI
> +        * config space.
> +        */
> +       if (eeh_probe_mode_dev() &&
> +           (pe->type & EEH_PE_PHB) &&
> +           (pe->state & (EEH_PE_ISOLATED | EEH_PE_PHB_DEAD)))
> +               valid_cfg_log = false;
> +

I'm still unsure about that one. EEH_PE_ISOLATED could be the result
of a normal ER of PE#0 (which can happen for various reasons other
than a fence) in which case the config space is available and
interesting.

I would either not bother and collect the FF's, or make this specific
to fence and only fence.

Cheers,
Ben.