[PATCH v5 18/18] kvm: arm64: Allow tuning the physical address size for VM
From: Suzuki.Poulose@arm.com (Suzuki K Poulose)
Date: 2018-09-17 14:44:00
Also in:
kvm, kvmarm, lkml
From: Suzuki.Poulose@arm.com (Suzuki K Poulose)
Date: 2018-09-17 14:44:00
Also in:
kvm, kvmarm, lkml
Hi Peter, On 17/09/2018 15:20, Peter Maydell wrote:
On 17 September 2018 at 11:41, Suzuki K Poulose [off-list ref] wrote:quoted
Allow specifying the physical address size limit for a new VM via the kvm_type argument for the KVM_CREATE_VM ioctl. This allows us to finalise the stage2 page table as early as possible and hence perform the right checks on the memory slots without complication. The size is ecnoded as Log2(PA_Size) in bits[7:0] of the type field. For backward compatibility the value 0 is reserved and implies 40bits. Also, lift the limit of the IPA to host limit and allow lower IPA sizes (e.g, 32). The userspace could check the extension KVM_CAP_ARM_VM_PHYS_SHIFT for the availability of this feature. The cap check returns the maximum limit for the physical address shift supported by the host. Cc: Marc Zyngier <redacted> Cc: Christoffer Dall <cdall@kernel.org> Cc: Peter Maydel <redacted>Typo: my surname has two "l"s in it.
Sorry about that. I have fixed this locally. Btw, did you get a chance to look at the patch itself ? If you did, are you fine with the API ? Suzuki