> Are you aware of any work that needs doing in the wider QEMU to support > nested virt or should it just be a case of doing the plumbing inaccel/hvf to > turn it on?
I’m not the greatest person to chime in unfortunately as I’m not an expert on QEMU by any means. What I can offer that may be of assistance: - Fundamentally, the APIs expose the EL2 states. The state shadowing is managed by Hypervisor.framework directly. - The new GIC APIs take care of interrupt injection, and would need to be used in concert with the EL2 APIs if you need interrupt support (highly likely 😬). This would be where I’d investigate on the QEMU end first to see if this would fit within the architecture without a bunch of reworks. https://developer.apple.com/documentation/hypervisor/hv_gic_create(_:) > On Jul 16, 2025, at 5:17 AM, Alex Bennée <alex.ben...@linaro.org> wrote: > > Danny Canter <danny_can...@apple.com <mailto:danny_can...@apple.com>> writes: > >> Joelle is correct, M3 and newer SoCs have support for the EL2 APIs. > > Thanks for the confirmation. I'm looking at getting a M4 Mini for my > team so we can help review and test patches for HVF going forward. > > Are you aware of any work that needs doing in the wider QEMU to support > nested virt or should it just be a case of doing the plumbing in > accel/hvf to turn it on? > >> >> -Danny >> >>> On Jul 15, 2025, at 8:53 AM, Joelle van Dyne <j...@getutm.app> wrote: >>> >>> UTM currently supports NV only with the Apple Virtualization backend, >>> not QEMU HVF. While M2 supports NV, it is not enabled by XNU kernel >>> and `hv_vm_config_get_el2_supported` returns false. I heard there was >>> some compatibility issue in the hardware. M3 and newer generations >>> fully support NV in hardware and by XNU. >>> >>> On Tue, Jul 15, 2025 at 4:51 AM Marc Zyngier <m...@kernel.org> wrote: >>>> >>>> On Tue, 15 Jul 2025 12:15:52 +0100, >>>> Alex Bennée <alex.ben...@linaro.org> wrote: >>>> >>>>> - do we know which Apple silicon supports FEAT_NV2? >>>> >>>> M2 and latter definitely support FEAT_NV2. That's how KVM NV support >>>> has been developed for two years until I was given better HW. >>>> >>>> Whether Apple supports NV on M2 in HVF, I have no idea. The rumour >>>> mill says "no", but I don't have a way to check. The M3 I use at $WORK >>>> is definitely able to give me EL2 without VHE with UTM. I haven't >>>> played with M4, but I have it on the record that it behaves like M3 >>>> with UTM. >>>> >>>> M. >>>> >>>> -- >>>> Without deviation from the norm, progress is not possible. > > -- > Alex Bennée > Virtualisation Tech Lead @ Linaro
