This is a note to let you know that I've just added the patch titled

kvm: nVMX: VMCLEAR should not cause the vCPU to shut down

to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: kvm-nvmx-vmclear-should-not-cause-the-vcpu-to-shut-down.patch and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From foo@baz Tue Dec 12 13:26:17 CET 2017

From: Jim Mattson jmattson@google.com Date: Thu, 2 Mar 2017 12:41:48 -0800 Subject: kvm: nVMX: VMCLEAR should not cause the vCPU to shut down

From: Jim Mattson jmattson@google.com

[ Upstream commit 587d7e72aedca91cee80c0a56811649c3efab765 ]

VMCLEAR should silently ignore a failure to clear the launch state of the VMCS referenced by the operand.

Signed-off-by: Jim Mattson jmattson@google.com [Changed "kvm_write_guest(vcpu->kvm" to "kvm_vcpu_write_guest(vcpu".] Signed-off-by: Radim Krčmář rkrcmar@redhat.com

Signed-off-by: Sasha Levin alexander.levin@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/kvm/vmx.c | 22 ++++------------------ 1 file changed, 4 insertions(+), 18 deletions(-)

--- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -7203,9 +7203,8 @@ static int handle_vmoff(struct kvm_vcpu static int handle_vmclear(struct kvm_vcpu *vcpu) { struct vcpu_vmx *vmx = to_vmx(vcpu); + u32 zero = 0; gpa_t vmptr; - struct vmcs12 *vmcs12; - struct page *page;

if (!nested_vmx_check_permission(vcpu)) return 1; @@ -7216,22 +7215,9 @@ static int handle_vmclear(struct kvm_vcp if (vmptr == vmx->nested.current_vmptr) nested_release_vmcs12(vmx);

- page = nested_get_page(vcpu, vmptr); - if (page == NULL) { - /* - * For accurate processor emulation, VMCLEAR beyond available - * physical memory should do nothing at all. However, it is - * possible that a nested vmx bug, not a guest hypervisor bug, - * resulted in this case, so let's shut down before doing any - * more damage: - */ - kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu); - return 1; - } - vmcs12 = kmap(page); - vmcs12->launch_state = 0; - kunmap(page); - nested_release_page(page); + kvm_vcpu_write_guest(vcpu, + vmptr + offsetof(struct vmcs12, launch_state), + &zero, sizeof(zero));

nested_free_vmcs02(vmx, vmptr);

Patches currently in stable-queue which might be from jmattson@google.com are

queue-4.9/kvm-nvmx-reset-nested_run_pending-if-the-vcpu-is-going-to-be-reset.patch queue-4.9/kvm-nvmx-vmclear-should-not-cause-the-vcpu-to-shut-down.patch queue-4.9/kvm-vmx-remove-i-o-port-0x80-bypass-on-intel-hosts.patch