This is a note to let you know that I've just added the patch titled
KVM: VMX: Do not advertise RDPID if ENABLE_RDTSCP control is unsupported
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
kvm-vmx-do-not-advertise-rdpid-if-enable_rdtscp-control-is-unsupported.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 8aec21c04caa2000f91cf8822ae0811e4b0c3971 Mon Sep 17 00:00:00 2001
From: Sean Christopherson <seanjc@xxxxxxxxxx>
Date: Tue, 4 May 2021 10:17:20 -0700
Subject: KVM: VMX: Do not advertise RDPID if ENABLE_RDTSCP control is unsupported
From: Sean Christopherson <seanjc@xxxxxxxxxx>
commit 8aec21c04caa2000f91cf8822ae0811e4b0c3971 upstream.
Clear KVM's RDPID capability if the ENABLE_RDTSCP secondary exec control is
unsupported. Despite being enumerated in a separate CPUID flag, RDPID is
bundled under the same VMCS control as RDTSCP and will #UD in VMX non-root
if ENABLE_RDTSCP is not enabled.
Fixes: 41cd02c6f7f6 ("kvm: x86: Expose RDPID in KVM_GET_SUPPORTED_CPUID")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Message-Id: <20210504171734.1434054-2-seanjc@xxxxxxxxxx>
Reviewed-by: Jim Mattson <jmattson@xxxxxxxxxx>
Reviewed-by: Reiji Watanabe <reijiw@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/kvm/vmx/vmx.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7302,9 +7302,11 @@ static __init void vmx_set_cpu_caps(void
if (!cpu_has_vmx_xsaves())
kvm_cpu_cap_clear(X86_FEATURE_XSAVES);
- /* CPUID 0x80000001 */
- if (!cpu_has_vmx_rdtscp())
+ /* CPUID 0x80000001 and 0x7 (RDPID) */
+ if (!cpu_has_vmx_rdtscp()) {
kvm_cpu_cap_clear(X86_FEATURE_RDTSCP);
+ kvm_cpu_cap_clear(X86_FEATURE_RDPID);
+ }
if (cpu_has_vmx_waitpkg())
kvm_cpu_cap_check_and_set(X86_FEATURE_WAITPKG);
Patches currently in stable-queue which might be from seanjc@xxxxxxxxxx are
queue-5.10/kvm-vmx-disable-preemption-when-probing-user-return-msrs.patch
queue-5.10/kvm-vmx-do-not-advertise-rdpid-if-enable_rdtscp-control-is-unsupported.patch
queue-5.10/crypto-ccp-free-sev-device-if-sev-init-fails.patch
queue-5.10/kvm-x86-mmu-remove-the-defunct-update_pte-paging-hook.patch
queue-5.10/kvm-lapic-accurately-guarantee-busy-wait-for-timer-t.patch
queue-5.10/kvm-x86-move-rdpid-emulation-intercept-to-its-own-enum.patch
queue-5.10/kvm-x86-emulate-rdpid-only-if-rdtscp-is-supported.patch
