Hi Christoffer, On 2017/5/10 20:20, Christoffer Dall wrote: > On Wed, May 10, 2017 at 05:15:04PM +0800, gengdongjiu wrote: >> Thanks James's explanation. >> >> Hi Christoffer, >> >> On 2017/5/9 22:28, James Morse wrote: >>> Hi Christoffer, >>> >>> On 08/05/17 18:54, Christoffer Dall wrote: >>>> On Mon, May 08, 2017 at 06:28:02PM +0100, James Morse wrote: >>>> I must admit I am losing track of exactly what this proposed API was >>>> supposed to do. >>> >>> There are two, and we keep jumping between them! >>> This is about two notification methods APEI has for arm64, 'SEA' and 'SEI'. >>> >>> SEA is synchronous and looks like a data abort. Qemu/kvmtool can inject these >>> today using the KVM_GET/SET_ONE_REG API whenever it wants to. >>> >>> SEI uses SError, is asynchronous and can be masked. In addition these need to be >>> consumed/synchronised by the ESB instruction, even when executed by a guest. >>> Hardware has the necessary bits to drive all this, we need to expose an API to >>> drive it. >>> >>> (I try to spell them out each time so I don't confuse SEI with something >>> synchronous!) >>> >>> >>> This patch was about SEA. I think you've answered our question: >> >> we are talking about the SEA(synchronous data abort) injection two methods: >> >> (1)change vcpu registers in the Qemu/kvmtools and using the KVM_GET/SET_ONE_REG API to set. > > Yes, if this is possible, why would you want something more? we will use this method. > >> (2)using existed in-kernel API "kvm_inject_dabt" to inject through IOCTL command from Qemu. >> > > I'm not really going to consider this, because "use internal API from > userspace" doesn't work. > > So this should be: > > (2) Introduce a new API to do X. you can ignore the second method, now we will not use it. > > I still think you know what my preference is; use the existing API if at > all possible. > > Thanks, > -Christoffer > > . >
