KVM: nVMX: Don't propagate vmcs12's PERF_GLOBAL_CTRL settings to vmcs02
authorSean Christopherson <seanjc@google.com>
Tue, 30 Aug 2022 13:37:21 +0000 (15:37 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 10 Nov 2022 17:14:14 +0000 (18:14 +0100)
commit8364786152d5abf887162612c23f932d8cda164f
treea8b04290fcc76ba3d24bcf4c068d96f73cdf1eef
parent523e1dd9f8d4d8cf064488473ef518c8dedcfeec
KVM: nVMX: Don't propagate vmcs12's PERF_GLOBAL_CTRL settings to vmcs02

[ Upstream commit def9d705c05eab3fdedeb10ad67907513b12038e ]

Don't propagate vmcs12's VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL to vmcs02.
KVM doesn't disallow L1 from using VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL
even when KVM itself doesn't use the control, e.g. due to the various
CPU errata that where the MSR can be corrupted on VM-Exit.

Preserve KVM's (vmcs01) setting to hopefully avoid having to toggle the
bit in vmcs02 at a later point.  E.g. if KVM is loading PERF_GLOBAL_CTRL
when running L1, then odds are good KVM will also load the MSR when
running L2.

Fixes: 8bf00a529967 ("KVM: VMX: add support for switching of PERF_GLOBAL_CTRL")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20220830133737.1539624-18-vkuznets@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
arch/x86/kvm/vmx/nested.c