Re: [PATCH v4 00/14] KVM: arm64: Add KVM_PRE_FAULT_MEMORY support

Hi Lorenzo,

On Wed, 23 Sep 2026 16:15:43 +0100, "Lorenzo Stoakes (ARM)"
[off-list ref] wrote:

This series implements the KVM stage 2 page table pre-faulting feature for
arm64.

Retested as follows (let's see if this one sticks ;) ):

QEMU/arm64 -cpu max:
- guests boot on VHE, nVHE and protected-mode hosts, protected guests included
- pre_fault_memory_test (all guest modes, anonymous, THP, hugetlb and
shmem backing) and nv_pre_fault_memory_test pass
- pre-faulting an uninitialised vCPU returns -ENOEXEC
- a failed guest_memfd pre-fault leaves kvm_run's exit_reason alone
- dirty_log_test, demand_paging_test, mmu_stress_test and
stage2_block_transitions also pass

Apple M4 (nVHE, 4K and 16K pages):
- pre_fault_memory_test passes on the five guest modes available
there, with the same backings
- in protected mode (4K pages), the cap isn't advertised, the ioctl
returns -EOPNOTSUPP before and after vCPU init, and guests boot

Tested-by: Fuad Tabba <fuad.tabba@linux.dev>

Cheers,
/fuad