* FAILED: patch "[PATCH] KVM: nVMX: Always enable TSC scaling for L2 when it was" failed to apply to 5.19-stable tree
@ 2022-08-12 15:30 gregkh
0 siblings, 0 replies; only message in thread
From: gregkh @ 2022-08-12 15:30 UTC (permalink / raw)
To: vkuznets, mlevitsk, seanjc; +Cc: stable
The patch below does not apply to the 5.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 156b9d76e8822f2956c15029acf2d4b171502f3a Mon Sep 17 00:00:00 2001
From: Vitaly Kuznetsov <vkuznets@redhat.com>
Date: Tue, 12 Jul 2022 15:50:09 +0200
Subject: [PATCH] KVM: nVMX: Always enable TSC scaling for L2 when it was
enabled for L1
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: d041b5ea93352b ("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>
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 778f82015f03..bfa366938c49 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -2284,7 +2284,6 @@ 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,
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2022-08-12 15:30 FAILED: patch "[PATCH] KVM: nVMX: Always enable TSC scaling for L2 when it was" failed to apply to 5.19-stable tree gregkh
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