On Thu, Jul 02, 2015 at 07:11:52PM +1000, Alexey Kardashevskiy wrote: > On 04/02/2015 03:46 PM, David Gibson wrote: > >On Thu, Apr 02, 2015 at 03:28:11PM +1100, Alexey Kardashevskiy wrote: > >>On 11/19/2014 04:48 PM, Aravinda Prasad wrote: > >>> > >>> > >>>On Tuesday 11 November 2014 08:54 AM, David Gibson wrote: > >>> > >>>[..] > >>> > >>>> > >>>>So, this may not still be possible depending on whether the KVM side > >>>>of this is already merged, but it occurs to me that there's a simpler > >>>>way. > >>>> > >>>>Rather than mucking about with having to update the hypervisor on the > >>>>RTAS location, they have qemu copy the code out of RTAS, patch it and > >>>>copy it back into the vector, you could instead do this: > >>>> > >>>> 1. Make KVM instead of immediately delivering a 0x200 for a guest > >>>>machine check, cause a special exit to qemu. > >>>> > >>>> 2. Have the register-nmi RTAS call store the guest side MC handler > >>>>address in the spapr structure, but perform no actual guest code > >>>>patching. > >>>> > >>>> 3. Allocate the error log buffer independently from the RTAS blob, > >>>>so qemu always knows where it is. > >>>> > >>>> 4. When qemu gets the MC exit condition, instead of going via a > >>>>patched 0x200 vector, just directly set the guest register state and > >>>>jump straight into the guest side MC handler. > >>>> > >>> > >>>Before I proceed further I would like to know what others think about > >>>the approach proposed above (except for step 3 - as per PAPR the error > >>>log buffer should be part of RTAS blob and hence we cannot have error > >>>log buffer independent of RTAS blob). > >>> > >>>Alex, Alexey, Ben: Any thoughts? > >> > >> > >>Any updates about FWNMI? Thanks > > > >Huh.. I'd completely forgotten about this. Aravinda, can you repost > >your latest work on this? > > > Aravinda disappeared...
Ok, well someone who cares about FWNMI is going to have to start
sending something, or it won't happen.
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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