From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt Date: Wed, 21 May 2014 00:12:11 +0000 Subject: Re: [PATCH 4/4] powerpc/eeh: Avoid event on passed PE Message-Id: <1400631131.3986.144.camel@pasglop> List-Id: References: <1400574612-19411-1-git-send-email-gwshan@linux.vnet.ibm.com> <1400574612-19411-5-git-send-email-gwshan@linux.vnet.ibm.com> <537B3B97.3020100@suse.de> <20140520115606.GB20397@shangw> In-Reply-To: <20140520115606.GB20397@shangw> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Gavin Shan Cc: aik@ozlabs.ru, Alexander Graf , kvm-ppc@vger.kernel.org, alex.williamson@redhat.com, qiudayu@linux.vnet.ibm.com, linuxppc-dev@lists.ozlabs.org On Tue, 2014-05-20 at 21:56 +1000, Gavin Shan wrote: .../... > >I think what you want is an irqfd that the in-kernel eeh code > >notifies when it sees a failure. When such an fd exists, the kernel > >skips its own error handling. > > > > Yeah, it's a good idea and something for me to improve in phase II. We > can discuss for more later. For now, what I have in my head is something > like this: However, this would be a deviation from (or extension of) PAPR. At the moment, the way things work in PAPR is that the guest is responsible for querying the EEH state when something "looks" like an error (ie, getting ff's back). This is also how it works in pHyp. We have an interrupt path in the host when doing "native" EEH, and it would be nice to extend PAPR to also be able to shoot an event to the guest possibly using RTAS events, but let's get the basics working and upstream first. Cheers, Ben.