From mboxrd@z Thu Jan 1 00:00:00 1970 From: Suzuki K Poulose Subject: Re: [PATCH v5 18/18] kvm: arm64: Allow tuning the physical address size for VM Date: Mon, 17 Sep 2018 15:43:53 +0100 Message-ID: References: <20180917104144.19188-1-suzuki.poulose@arm.com> <20180917104144.19188-19-suzuki.poulose@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Cc: arm-mail-list , kvmarm@lists.cs.columbia.edu, kvm-devel , Marc Zyngier , Christoffer Dall , Eric Auger , Paolo Bonzini , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , Will Deacon , Catalin Marinas , James Morse , Dave P Martin , julien.grall@arm.com, lkml - Kernel Mailing List To: Peter Maydell Return-path: In-Reply-To: Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org Hi Peter, On 17/09/2018 15:20, Peter Maydell wrote: > On 17 September 2018 at 11:41, Suzuki K Poulose wrote: >> 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 >> Cc: Christoffer Dall >> Cc: Peter Maydel > > 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