[PATCH 0/4] KVM: add KVM_CREATE_VM2 to allow dynamic kvm->vcpus array

From: "Radim Krčmář" <rkrcmar@redhat.com>
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: Christoffer Dall <cdall@linaro.org>,
	Marc Zyngier <marc.zyngier@arm.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Christian Borntraeger <borntraeger@de.ibm.com>,
	Cornelia Huck <cornelia.huck@de.ibm.com>,
	James Hogan <james.hogan@imgtec.com>,
	Paul Mackerras <paulus@ozlabs.org>,
	Alexander Graf <agraf@suse.com>
Subject: [PATCH 0/4] KVM: add KVM_CREATE_VM2 to allow dynamic kvm->vcpus array
Date: Thu, 13 Apr 2017 22:19:47 +0200	[thread overview]
Message-ID: <20170413201951.11939-1-rkrcmar@redhat.com> (raw)

The basic idea is to let userspace provide the desired maximal number of
VCPUs and allocate only necessary memory for them.

The goal is to freeze KVM_MAX_VCPUS at its current level and only increase the
new KVM_MAX_CONFIGURABLE_VCPUS, probably directly to INT_MAX/KVM_VCPU_ID, so we
don't have to worry about it for a while.

PPC should be interested in this as they set KVM_MAX_VCPUS to NR_CPUS
and probably waste few pages for every guest this way.

Radim Krčmář (4):
  KVM: remove unused __KVM_HAVE_ARCH_VM_ALLOC
  KVM: allocate kvm->vcpus separately
  KVM: add KVM_CREATE_VM2 system ioctl
  KVM: x86: enable configurable MAX_VCPU

 Documentation/virtual/kvm/api.txt | 28 +++++++++++++++
 arch/x86/include/asm/kvm_host.h   |  1 +
 arch/x86/kvm/irq_comm.c           |  4 +--
 include/linux/kvm_host.h          | 23 +++++-------
 include/uapi/linux/kvm.h          |  8 +++++
 virt/kvm/kvm_main.c               | 76 +++++++++++++++++++++++++++++++++------
 6 files changed, 114 insertions(+), 26 deletions(-)

-- 
2.12.0