linux-kernel - [GIT PULL] KVM: x86: VMX changes for 6.17

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Message-ID: <20250725220713.264711-13-seanjc@google.com>
Date: Fri, 25 Jul 2025 15:07:12 -0700
From: Sean Christopherson <seanjc@...gle.com>
To: Paolo Bonzini <pbonzini@...hat.com>
Cc: kvm@...r.kernel.org, linux-kernel@...r.kernel.org, 
	Sean Christopherson <seanjc@...gle.com>
Subject: [GIT PULL] KVM: x86: VMX changes for 6.17

Add a sub-ioctl to allow getting TDX VMs into TEARDOWN before the last reference
to the VM is put, so that reclaiming the VM's memory doesn't have to jump
through all the hoops needed to reclaim memory from a live TD, which are quite
costly, especially for large VMs.

The following changes since commit 347e9f5043c89695b01e66b3ed111755afcf1911:

  Linux 6.16-rc6 (2025-07-13 14:25:58 -0700)

are available in the Git repository at:

  https://github.com/kvm-x86/linux.git tags/kvm-x86-vmx-6.17

for you to fetch changes up to dcab95e533642d8f733e2562b8bfa5715541e0cf:

  KVM: TDX: Add sub-ioctl KVM_TDX_TERMINATE_VM (2025-07-21 16:23:02 -0700)

----------------------------------------------------------------
KVM VMX changes for 6.17

Add a TDX sub-ioctl, KVM_TDX_TERMINATE_VM, to let userspace mark a VM as dead,
and most importantly release its HKID, prior to dropping the last reference to
the VM.  Releasing the HKID moves the VM to TDX's TEARDOWN state, which allows
pages to be reclaimed directly and ultimately reduces total reclaim time by a
factor of 10x or more.

----------------------------------------------------------------
Sean Christopherson (1):
      KVM: TDX: Add sub-ioctl KVM_TDX_TERMINATE_VM

 Documentation/virt/kvm/x86/intel-tdx.rst | 22 ++++++++++++++++++-
 arch/x86/include/uapi/asm/kvm.h          |  7 ++++++-
 arch/x86/kvm/vmx/tdx.c                   | 36 +++++++++++++++++++++++++-------
 3 files changed, 55 insertions(+), 10 deletions(-)