From f7eaeb0ad815730dc63e8974e6f9f4d93b8ca8bb Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Mon, 5 Mar 2018 12:04:36 -0800 Subject: [PATCH] KVM: VMX: don't configure RM TSS for unrestricted guest MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit An unrestricted guest can run with CR0.PG==0 and/or CR0.PE==0, e.g. it can run in Real Mode without requiring host emulation. The RM TSS is only used for emulating RM, i.e. it will never be used when unrestricted guest is enabled and so doesn't need to be configured. Signed-off-by: Sean Christopherson Signed-off-by: Radim Krčmář --- arch/x86/kvm/vmx.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 5726cee..a5d2c69 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -6044,6 +6044,9 @@ static int vmx_set_tss_addr(struct kvm *kvm, unsigned int addr) { int ret; + if (enable_unrestricted_guest) + return 0; + ret = x86_set_memory_region(kvm, TSS_PRIVATE_MEMSLOT, addr, PAGE_SIZE * 3); if (ret) -- 2.7.4