Date:   Wed, 17 Nov 2021 09:13:55 +0000
Message-ID: <87zgq36t64.wl-maz@kernel.org>
From:   Marc Zyngier <maz@kernel.org>
To:     Vitaly Kuznetsov <vkuznets@redhat.com>
Cc:     kvm@vger.kernel.org, Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Eduardo Habkost <ehabkost@redhat.com>,
        Andrew Jones <drjones@redhat.com>,
        Huacai Chen <chenhuacai@kernel.org>,
        Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>,
        Anup Patel <anup.patel@wdc.com>,
        Paul Mackerras <paulus@ozlabs.org>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Christian Borntraeger <borntraeger@de.ibm.com>,
        Janosch Frank <frankja@linux.ibm.com>, kvm-ppc@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-mips@vger.kernel.org,
        kvm-riscv@lists.infradead.org, linux-s390@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/6] KVM: arm64: Cap KVM_CAP_NR_VCPUS by kvm_arm_default_max_vcpus()
In-Reply-To: <20211116163443.88707-2-vkuznets@redhat.com>
References: <20211116163443.88707-1-vkuznets@redhat.com>
        <20211116163443.88707-2-vkuznets@redhat.com>
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On Tue, 16 Nov 2021 16:34:38 +0000,
Vitaly Kuznetsov <vkuznets@redhat.com> wrote:
> 
> Generally, it doesn't make sense to return the recommended maximum number
> of vCPUs which exceeds the maximum possible number of vCPUs.
> 
> Note: ARM64 is special as the value returned by KVM_CAP_MAX_VCPUS differs
> depending on whether it is a system-wide ioctl or a per-VM one. Previously,
> KVM_CAP_NR_VCPUS didn't have this difference and it seems preferable to
> keep the status quo. Cap KVM_CAP_NR_VCPUS by kvm_arm_default_max_vcpus()
> which is what gets returned by system-wide KVM_CAP_MAX_VCPUS.
> 
> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>

Acked-by: Marc Zyngier <maz@kernel.org>

	M.

-- 
Without deviation from the norm, progress is not possible.