Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Subject: Re: [PATCH v1 14/16] kvm: arm64: Switch to per VM IPA
To:     Christoffer Dall <christoffer.dall@linaro.org>
Cc:     linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org,
        kvmarm@lists.cs.columbia.edu, marc.zyngier@arm.com,
        linux-kernel@vger.kernel.org, kristina.martsenko@arm.com,
        peter.maydell@linaro.org, pbonzini@redhat.com, rkrcmar@redhat.com,
        will.deacon@arm.com, ard.biesheuvel@linaro.org,
        mark.rutland@arm.com, catalin.marinas@arm.com,
        Christoffer Dall <cdall@linaro.org>
References: <20180109190414.4017-1-suzuki.poulose@arm.com>
 <20180109190414.4017-15-suzuki.poulose@arm.com> <20180208110035.GG29286@cbox>
From:   Suzuki K Poulose <Suzuki.Poulose@arm.com>
Message-ID: <94aae952-d6c0-0a69-955f-81885ddb2f06@arm.com>
Date:   Thu, 8 Feb 2018 17:22:29 +0000
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101
 Thunderbird/52.5.2
MIME-Version: 1.0
In-Reply-To: <20180208110035.GG29286@cbox>
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On 08/02/18 11:00, Christoffer Dall wrote:
> On Tue, Jan 09, 2018 at 07:04:09PM +0000, Suzuki K Poulose wrote:
>> Now that we can manage the stage2 page table per VM, switch the
>> configuration details to per VM instance. We keep track of the
>> IPA bits, number of page table levels and the VTCR bits (which
>> depends on the IPA and the number of levels).
>>
>> Cc: Marc Zyngier <marc.zyngier@arm.com>
>> Cc: Christoffer Dall <cdall@linaro.org>
>> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
>> ---
>>   arch/arm/include/asm/kvm_mmu.h          |  1 +
>>   arch/arm64/include/asm/kvm_host.h       | 12 ++++++++++++
>>   arch/arm64/include/asm/kvm_mmu.h        | 22 ++++++++++++++++++++--
>>   arch/arm64/include/asm/stage2_pgtable.h |  1 -
>>   arch/arm64/kvm/hyp/switch.c             |  3 +--
>>   virt/kvm/arm/arm.c                      |  2 +-
>>   6 files changed, 35 insertions(+), 6 deletions(-)
>>
>> diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h
>> index 440c80589453..dd592fe45660 100644
>> --- a/arch/arm/include/asm/kvm_mmu.h
>> +++ b/arch/arm/include/asm/kvm_mmu.h
>> @@ -48,6 +48,7 @@
>>   #define kvm_vttbr_baddr_mask(kvm)	VTTBR_BADDR_MASK
>>   
>>   #define stage2_pgd_size(kvm)	(PTRS_PER_S2_PGD * sizeof(pgd_t))
>> +#define kvm_init_stage2_config(kvm)	do { } while (0)
>>   int create_hyp_mappings(void *from, void *to, pgprot_t prot);
>>   int create_hyp_io_mappings(void *from, void *to, phys_addr_t);
>>   void free_hyp_pgds(void);
>> diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
>> index 9a9ddeb33c84..1e66e5ab3dde 100644
>> --- a/arch/arm64/include/asm/kvm_host.h
>> +++ b/arch/arm64/include/asm/kvm_host.h
>> @@ -64,6 +64,18 @@ struct kvm_arch {
>>   	/* VTTBR value associated with above pgd and vmid */
>>   	u64    vttbr;
>>   
>> +	/* Private bits of VTCR_EL2 for this VM */
>> +	u64    vtcr_private;
> 
> As to my comments in the previous patch, why isn't this simply u64 vtcr;

nit: I haven't received your response to the previous patch.

We could. I thought this gives a bit more clarity on what changes per-VM.

Thanks
Suzuki