[05/23] KVM: nSVM: do not copy vmcb01->control blindly to vmcb02->control
diff mbox series

Message ID 20210302193343.313318-6-pbonzini@redhat.com
State New, archived
Headers show
Series
  • SVM queue for 5.13
Related show

Commit Message

Paolo Bonzini March 2, 2021, 7:33 p.m. UTC
Most fields were going to be overwritten by vmcb12 control fields, or
do not matter at all because they are filled by the processor on vmexit.
Therefore, we need not copy them from vmcb01 to vmcb02 on vmentry.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/kvm/svm/nested.c | 23 +++++++++++++++++++++--
 arch/x86/kvm/svm/svm.h    |  2 +-
 2 files changed, 22 insertions(+), 3 deletions(-)

Patch
diff mbox series

diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 4d136465dee1..f88d0614d9b8 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -428,9 +428,28 @@  static void nested_vmcb02_prepare_control(struct vcpu_svm *svm)
 {
 	const u32 mask = V_INTR_MASKING_MASK | V_GIF_ENABLE_MASK | V_GIF_MASK;
 
-	/* FIXME: go through each field one by one.  */
-	svm->nested.vmcb02.ptr->control = svm->vmcb01.ptr->control;
+	/*
+	 * Filled at exit: exit_code, exit_code_hi, exit_info_1, exit_info_2,
+	 * exit_int_info, exit_int_info_err, next_rip, insn_len, insn_bytes.
+	 */
+
+	/*
+	 * Also covers avic_vapic_bar, avic_backing_page, avic_logical_id,
+	 * avic_physical_id.
+	 */
+	WARN_ON(svm->vmcb01.ptr->control.int_ctl & AVIC_ENABLE_MASK);
+
+	/* Copied from vmcb01.  msrpm_base can be overwritten later.  */
+	svm->vmcb->control.nested_ctl = svm->vmcb01.ptr->control.nested_ctl;
+	svm->vmcb->control.iopm_base_pa = svm->vmcb01.ptr->control.iopm_base_pa;
+	svm->vmcb->control.msrpm_base_pa = svm->vmcb01.ptr->control.msrpm_base_pa;
+
+	/* Done at vmrun: asid.  */
+
+	/* Also overwritten later if necessary.  */
+	svm->vmcb->control.tlb_ctl = TLB_CONTROL_DO_NOTHING;
 
+	/* nested_cr3.  */
 	if (nested_npt_enabled(svm))
 		nested_svm_init_mmu_context(&svm->vcpu);