mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-10-01 06:33:07 +00:00
Code Issues Releases Wiki Activity

KVM: nVMX: Always enable TSC scaling for L2 when it was enabled for L1

Browse source 
commit 156b9d76e8 upstream.

Windows 10/11 guests with Hyper-V role (WSL2) enabled are observed to
hang upon boot or shortly after when a non-default TSC frequency was
set for L1. The issue is observed on a host where TSC scaling is
supported. The problem appears to be that Windows doesn't use TSC
scaling for its guests, even when the feature is advertised, and KVM
filters SECONDARY_EXEC_TSC_SCALING out when creating L2 controls from
L1's VMCS. This leads to L2 running with the default frequency (matching
host's) while L1 is running with an altered one.

Keep SECONDARY_EXEC_TSC_SCALING in secondary exec controls for L2 when
it was set for L1. TSC_MULTIPLIER is already correctly computed and
written by prepare_vmcs02().

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Fixes: d041b5ea93 ("KVM: nVMX: Enable nested TSC scaling")
Cc: stable@vger.kernel.org
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Link: https://lore.kernel.org/r/20220712135009.952805-1-vkuznets@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Vitaly Kuznetsov 2022-07-12 15:50:09 +02:00 committed by Greg Kroah-Hartman
parent 358da81ee2
commit 5149d3bcd0
1 changed files with 0 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

1
arch/x86/kvm/vmx/nested.c
View file

@ -2283,7 +2283,6 @@ static void prepare_vmcs02_early(struct vcpu_vmx *vmx, struct loaded_vmcs *vmcs0
SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY |
SECONDARY_EXEC_APIC_REGISTER_VIRT |
SECONDARY_EXEC_ENABLE_VMFUNC |
SECONDARY_EXEC_TSC_SCALING |
SECONDARY_EXEC_DESC);
if (nested_cpu_has(vmcs12,