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Subject: Re: [PATCH v1 2/3] powerpc/powernv: Support PCI error injection
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Mike Qiu <qiudayu@linux.vnet.ibm.com>
Date: Tue, 22 Jul 2014 13:21:59 +1000
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Cc: aik@ozlabs.ru, linuxppc-dev@lists.ozlabs.org,
 Gavin Shan <gwshan@linux.vnet.ibm.com>, kvm-ppc@vger.kernel.org, agraf@suse.de
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On Tue, 2014-07-22 at 11:10 +0800, Mike Qiu wrote:
> On 07/22/2014 06:49 AM, Benjamin Herrenschmidt wrote:
> > On Mon, 2014-07-21 at 16:06 +0800, Mike Qiu wrote:
> >>> I don't like this. I much prefer have dedicated error injection files
> >>> in their respective locations, something for PCI under the corresponding
> >>> PCI bridge etc...
> >> So PowerNV error injection will be designed rely on debugfs been
> >> configured, right?
> > Not necessarily. If we create a better debugfs layout for our PHBs, then
> > yes. It might be useful to provide more info in there for example access
> > to some of the counters ...
> >
> > But on the other hand, for error injection in general, I wonder if we should
> > be under sysfs instead... something to study a bit.
> 
> In pHyp, general error injection use syscall:
> 
>      #define __NR_rtas        255
> 
> I don't know if it is a good idea to reuse this syscall for PowerNV.
> 
> At least, it is another choice without sysfs rely.

No, we certainly don't want that RTAS stuff. I though Linux had some
kind of error injection infrastructure nowadays... somebody needs to
have a look.

Cheers,
Ben.