[PATCH v4 6/9] KVM: nSVM: move kvm_set_cr3() after nested_svm_uninit_mmu_context()

From: Vitaly Kuznetsov
Date: Fri Jul 10 2020 - 10:12:48 EST


kvm_mmu_new_pgd() refers to arch.mmu and at this point it still references
arch.guest_mmu while arch.root_mmu is expected.

Note, the change is effectively a nop: when !npt_enabled,
nested_svm_uninit_mmu_context() does nothing (as we don't do
nested_svm_init_mmu_context()) and with npt_enabled we don't
do kvm_set_cr3() but we're about to switch to nested_svm_load_cr3().

No functional change intended.

Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
---
arch/x86/kvm/svm/nested.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 180929f3dbef..2c308dfa5468 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -611,12 +611,6 @@ int nested_svm_vmexit(struct vcpu_svm *svm)
svm_set_efer(&svm->vcpu, hsave->save.efer);
svm_set_cr0(&svm->vcpu, hsave->save.cr0 | X86_CR0_PE);
svm_set_cr4(&svm->vcpu, hsave->save.cr4);
- if (npt_enabled) {
- svm->vmcb->save.cr3 = hsave->save.cr3;
- svm->vcpu.arch.cr3 = hsave->save.cr3;
- } else {
- (void)kvm_set_cr3(&svm->vcpu, hsave->save.cr3);
- }
kvm_rax_write(&svm->vcpu, hsave->save.rax);
kvm_rsp_write(&svm->vcpu, hsave->save.rsp);
kvm_rip_write(&svm->vcpu, hsave->save.rip);
@@ -636,6 +630,14 @@ int nested_svm_vmexit(struct vcpu_svm *svm)
kvm_vcpu_unmap(&svm->vcpu, &map, true);

nested_svm_uninit_mmu_context(&svm->vcpu);
+
+ if (npt_enabled) {
+ svm->vmcb->save.cr3 = hsave->save.cr3;
+ svm->vcpu.arch.cr3 = hsave->save.cr3;
+ } else {
+ (void)kvm_set_cr3(&svm->vcpu, hsave->save.cr3);
+ }
+
kvm_mmu_reset_context(&svm->vcpu);
kvm_mmu_load(&svm->vcpu);

--
2.25.4