From d76c7fbc01b29257359ed8b0d16d662e725b7bf9 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Tue, 28 Jan 2020 15:53:44 -0800 Subject: KVM: x86: Mark CR4.UMIP as reserved based on associated CPUID bit Re-add code to mark CR4.UMIP as reserved if UMIP is not supported by the host. The UMIP handling was unintentionally dropped during a recent refactoring. Not flagging CR4.UMIP allows the guest to set its CR4.UMIP regardless of host support or userspace desires. On CPUs with UMIP support, including emulated UMIP, this allows the guest to enable UMIP against the wishes of the userspace VMM. On CPUs without any form of UMIP, this results in a failed VM-Enter due to invalid guest state. Fixes: 345599f9a2928 ("KVM: x86: Add macro to ensure reserved cr4 bits checks stay in sync") Signed-off-by: Sean Christopherson Reviewed-by: Vitaly Kuznetsov Signed-off-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch') diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 6db92371ad21..fbabb2f06273 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -898,6 +898,8 @@ EXPORT_SYMBOL_GPL(kvm_set_xcr); __reserved_bits |= X86_CR4_PKE; \ if (!__cpu_has(__c, X86_FEATURE_LA57)) \ __reserved_bits |= X86_CR4_LA57; \ + if (!__cpu_has(__c, X86_FEATURE_UMIP)) \ + __reserved_bits |= X86_CR4_UMIP; \ __reserved_bits; \ }) -- cgit v1.2.3-59-g8ed1b