On Tue, Oct 31, 2017 at 07:35:35AM +0100, Christoffer Dall wrote: > Hi James, Catalin, and Will, > > On Thu, Oct 19, 2017 at 03:57:46PM +0100, James Morse wrote: > > Hello, > > > > The aim of this series is to enable IESB and add ESB-instructions to let us > > kick any pending RAS errors into firmware to be handled by firmware-first. > > > > Not all systems will have this firmware, so these RAS errors will become > > pending SErrors. We should take these as quickly as possible and avoid > > panic()ing for errors where we could have continued. > > > > This first part of this series reworks the DAIF masking so that SError is > > unmasked unless we are handling a debug exception. > > > > The last part provides the same minimal handling for SError that interrupt > > KVM. KVM is currently unable to handle SErrors during world-switch, unless > > they occur during a magic single-instruction window, it hyp-panics. I suspect > > this will be easier to fix once the VHE world-switch is further optimised. > > > > KVMs kvm_inject_vabt() needs updating for v8.2 as now we can specify an ESR, > > and all-zeros has a RAS meaning. > > > > KVM's existing 'impdef SError to the guest' behaviour probably needs revisiting. > > These are errors where we don't know what they mean, they may not be > > synchronised by ESB. Today we blame the guest. > > My half-baked suggestion would be to make a virtual SError pending, but then > > exit to user-space to give Qemu the change to quit (for virtual machines that > > don't generate SError), pend an SError with a new Qemu-specific ESR, or blindly > > continue and take KVMs default all-zeros impdef ESR. > > The KVM side of this series is looking pretty good. > > What are the merge plans for this? I am fine if you will take this via > the arm64 tree with our acks from the KVM side. Alternatively, I > suppose you can apply all the arm64 patches and provide us with a stable > branch for that? I'll take a look this afternoon, but we haven't had a linux next release since the 18th so I'm starting to get nervous about conflicts if I end up pulling in new trees now. Will _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
