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Subject: Re: [PATCH] powerpc/pseries: Avoid context switch in EEH reset if
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From: Benjamin Herrenschmidt <benh@au1.ibm.com>
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Cc: wenxiong@linux.vnet.ibm.com, linuxppc-dev@lists.ozlabs.org,
 Gavin Shan <gwshan@linux.vnet.ibm.com>, Brian J King <bjking1@us.ibm.com>
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On Mon, 2015-01-26 at 17:36 -0600, Brian King wrote:
> To set some context, this function is only used by ipr for some old
> broken adapters. These are adapters that are not supported on p8,
> so will never show up under OPAL, only PowerVM. I'm fine with looking
> at alternatives for the future, but I can't say I'm too excited about
> changing the calling requirements for an API that has been around
> for many years. Particularly given that this code is only needed for
> these old adapters. If its difficult to implement this for OPAL without
> noticeable delays, could we just return -EINVAL for this function on OPAL?,
> since its not needed there today anyway.

Because it's needed for other things nowadays afaik, though IPR is the only one
that needs this to be done at interrupt time...

In fact, even with IPR and the existing call, how do you wait for the link to come
back for a PERST ? That can take a while...

Ben.