2016-02-26 2:54 GMT-05:00 Christoffer Dall <christoffer.dall@xxxxxxxxxx>: > On Thu, Feb 25, 2016 at 12:45:45PM -0500, xu mike wrote: >> Hi Peter, >> >> 2016-02-25 10:30 GMT-05:00 Peter Maydell <peter.maydell@xxxxxxxxxx>: >> > >> > On 25 February 2016 at 15:17, xu mike <upennmike@xxxxxxxxx> wrote: >> > > I'm a student from the University of Pennsylvania. I want to try KVM on ARM >> > > boards. >> > > >> > > I have a Freescale IMX6 board [1] which has ARM Cortex A9 processors. >> > > I'm wondering if KVM can run on the Freescale IMX6 board? or >> > > Can KVM run on any ARM board with ARM Cortex A9 processors? >> > > >> > > I noticed at [2] that " KVM/ARM is designed specifically to work on ARM >> > > processors with the virtualization extensions enabled to run unmodified >> > > guest operating systems." >> > > I'm wondering if this statement is still true? >> > >> > Yes, it is. You need a CPU with the virtualization extensions, >> > and the A9 does not have them. You want (for instance) an A15 >> > or an A7. There are cheap A7-based development boards out there, >> > for instance the CubieTruck (which is not very fast but can run >> > a mainline Linux kernel and KVM so is a reasonable getting-started >> > development platform). >> >> >> Thank you very much for your quick reply! >> >> I'm wondering if KVM community has any plan to make KVM compatible >> with Cortex A9 processors? >> > > Not that I'm aware, no. > >> If someone, with linux scheduler development experiment but without >> porting experiment, wants to port KVM to Cortex A9, how hard could it >> be to port KVM onto Cortex A9 processor? > > As Peter said, ARM is not a virtualizable architecture, so you need > hardware support for virtualization to run hypervisors on an ARM system. > > Cortex-A9 does not have this support. > > You could implement something using either binary translation or > paravirtualization, but neither is something we're immediately > interested in accepting in mainline Linux. Right. I couldn't estimate how hard it will be to achieve the paravirtualization/binary translation in KVM.. Probably it may involve a lot of (assembly) code, since it requires to de-privilege those privileged instructions. :-( > > What is your use-case for running on A9 specifically, as opposed to a > CPU with virt support? The reason why I have to use A9 is because A9 has the special cache controller, called PL310 cache controller, which is not supported in A7 or A15. I want to use the special cache controller in virtualization environment. That's why I'm so addicted to A9. :-( If there is some latest ARM processor that has the PL310 cache controller and virtulaizaiton extension support, that will be awesome! However, I'm unaware of the ideal ARM processors. :-( Do you happen to know? Thank you so much for your time and help in this question! Best, Mike _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
