Patch "KVM: VMX: introduce alloc_loaded_vmcs" has been added to the 4.9-stable tree

[<gregkh@linuxfoundation.org>]

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

    KVM: VMX: introduce alloc_loaded_vmcs

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     kvm-vmx-introduce-alloc_loaded_vmcs.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 f21f165ef922c2146cc5bdc620f542953c41714b Mon Sep 17 00:00:00 2001
From: Paolo Bonzini <pbonzini@redhat.com>
Date: Thu, 11 Jan 2018 12:16:15 +0100
Subject: KVM: VMX: introduce alloc_loaded_vmcs

From: Paolo Bonzini <pbonzini@redhat.com>

commit f21f165ef922c2146cc5bdc620f542953c41714b upstream.

Group together the calls to alloc_vmcs and loaded_vmcs_init.  Soon we'll also
allocate an MSR bitmap there.

Cc: stable@vger.kernel.org       # prereq for Spectre mitigation
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/x86/kvm/vmx.c |   38 +++++++++++++++++++++++---------------
 1 file changed, 23 insertions(+), 15 deletions(-)

--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -3524,11 +3524,6 @@ static struct vmcs *alloc_vmcs_cpu(int c
 	return vmcs;
 }
 
-static struct vmcs *alloc_vmcs(void)
-{
-	return alloc_vmcs_cpu(raw_smp_processor_id());
-}
-
 static void free_vmcs(struct vmcs *vmcs)
 {
 	free_pages((unsigned long)vmcs, vmcs_config.order);
@@ -3547,6 +3542,22 @@ static void free_loaded_vmcs(struct load
 	WARN_ON(loaded_vmcs->shadow_vmcs != NULL);
 }
 
+static struct vmcs *alloc_vmcs(void)
+{
+	return alloc_vmcs_cpu(raw_smp_processor_id());
+}
+
+static int alloc_loaded_vmcs(struct loaded_vmcs *loaded_vmcs)
+{
+	loaded_vmcs->vmcs = alloc_vmcs();
+	if (!loaded_vmcs->vmcs)
+		return -ENOMEM;
+
+	loaded_vmcs->shadow_vmcs = NULL;
+	loaded_vmcs_init(loaded_vmcs);
+	return 0;
+}
+
 static void free_kvm_area(void)
 {
 	int cpu;
@@ -6949,6 +6960,7 @@ static int handle_vmon(struct kvm_vcpu *
 	struct vmcs *shadow_vmcs;
 	const u64 VMXON_NEEDED_FEATURES = FEATURE_CONTROL_LOCKED
 		| FEATURE_CONTROL_VMXON_ENABLED_OUTSIDE_SMX;
+	int r;
 
 	/* The Intel VMX Instruction Reference lists a bunch of bits that
 	 * are prerequisite to running VMXON, most notably cr4.VMXE must be
@@ -6988,11 +7000,9 @@ static int handle_vmon(struct kvm_vcpu *
 		return 1;
 	}
 
-	vmx->nested.vmcs02.vmcs = alloc_vmcs();
-	vmx->nested.vmcs02.shadow_vmcs = NULL;
-	if (!vmx->nested.vmcs02.vmcs)
+	r = alloc_loaded_vmcs(&vmx->nested.vmcs02);
+	if (r < 0)
 		goto out_vmcs02;
-	loaded_vmcs_init(&vmx->nested.vmcs02);
 
 	if (cpu_has_vmx_msr_bitmap()) {
 		vmx->nested.msr_bitmap =
@@ -9113,17 +9123,15 @@ static struct kvm_vcpu *vmx_create_vcpu(
 	if (!vmx->guest_msrs)
 		goto free_pml;
 
-	vmx->loaded_vmcs = &vmx->vmcs01;
-	vmx->loaded_vmcs->vmcs = alloc_vmcs();
-	vmx->loaded_vmcs->shadow_vmcs = NULL;
-	if (!vmx->loaded_vmcs->vmcs)
-		goto free_msrs;
 	if (!vmm_exclusive)
 		kvm_cpu_vmxon(__pa(per_cpu(vmxarea, raw_smp_processor_id())));
-	loaded_vmcs_init(vmx->loaded_vmcs);
+	err = alloc_loaded_vmcs(&vmx->vmcs01);
 	if (!vmm_exclusive)
 		kvm_cpu_vmxoff();
+	if (err < 0)
+		goto free_msrs;
 
+	vmx->loaded_vmcs = &vmx->vmcs01;
 	cpu = get_cpu();
 	vmx_vcpu_load(&vmx->vcpu, cpu);
 	vmx->vcpu.cpu = cpu;


Patches currently in stable-queue which might be from pbonzini@redhat.com are

queue-4.9/kvm-vmx-introduce-alloc_loaded_vmcs.patch
queue-4.9/kvm-nvmx-eliminate-vmcs02-pool.patch
queue-4.9/kvm-vmx-allow-direct-access-to-msr_ia32_spec_ctrl.patch
queue-4.9/kvm-x86-add-ibpb-support.patch
queue-4.9/kvm-svm-allow-direct-access-to-msr_ia32_spec_ctrl.patch
queue-4.9/kvm-nvmx-vmx_complete_nested_posted_interrupt-can-t-fail.patch
queue-4.9/x86-pti-make-unpoison-of-pgd-for-trusted-boot-work-for-real.patch
queue-4.9/kvm-vmx-make-msr-bitmaps-per-vcpu.patch
queue-4.9/kvm-nvmx-mark-vmcs12-pages-dirty-on-l2-exit.patch
queue-4.9/kvm-vmx-emulate-msr_ia32_arch_capabilities.patch