From 3aae0854b26aff303202c6f9542445f58b2539fe Mon Sep 17 00:00:00 2001 From: Vitaly Kuznetsov Date: Wed, 25 May 2022 13:59:48 +0200 Subject: i386: Hyper-V Direct TLB flush hypercall Hyper-V TLFS allows for L0 and L1 hypervisors to collaborate on L2's TLB flush hypercalls handling. With the correct setup, L2's TLB flush hypercalls can be handled by L0 directly, without the need to exit to L1. Signed-off-by: Vitaly Kuznetsov Message-Id: <20220525115949.1294004-6-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini --- docs/hyperv.txt | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'docs') diff --git a/docs/hyperv.txt b/docs/hyperv.txt index 4b132b1c94..14a7f449ea 100644 --- a/docs/hyperv.txt +++ b/docs/hyperv.txt @@ -262,6 +262,17 @@ Allow for extended GVA ranges to be passed to Hyper-V TLB flush hypercalls Requires: hv-tlbflush +3.25. hv-tlbflush-direct +========================= +The enlightenment is nested specific, it targets Hyper-V on KVM guests. When +enabled, it allows L0 (KVM) to directly handle TLB flush hypercalls from L2 +guest without the need to exit to L1 (Hyper-V) hypervisor. While the feature is +supported for both VMX (Intel) and SVM (AMD), the VMX implementation requires +Enlightened VMCS ('hv-evmcs') feature to also be enabled. + +Requires: hv-vapic +Recommended: hv-evmcs (Intel) + 4. Supplementary features ========================= -- cgit v1.2.3