Documentation/virt/kvm/api.rst | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
TSC_DEADLINE is now advertised unconditionally by KVM_GET_SUPPORTED_CPUID,
since commit 9be4ec35d668 ("KVM: x86: Advertise TSC_DEADLINE_TIMER in
KVM_GET_SUPPORTED_CPUID", 2024-12-18). Adjust the documentation to
reflect the new behavior.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
Documentation/virt/kvm/api.rst | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
index d90ae23c0a40..732e07b44d48 100644
--- a/Documentation/virt/kvm/api.rst
+++ b/Documentation/virt/kvm/api.rst
@@ -9265,9 +9265,10 @@ the local APIC.
The same is true for the ``KVM_FEATURE_PV_UNHALT`` paravirtualized feature.
-CPU[EAX=1]:ECX[24] (TSC_DEADLINE) is not reported by ``KVM_GET_SUPPORTED_CPUID``.
-It can be enabled if ``KVM_CAP_TSC_DEADLINE_TIMER`` is present and the kernel
-has enabled in-kernel emulation of the local APIC.
+On older versions of Linux, CPU[EAX=1]:ECX[24] (TSC_DEADLINE) is not reported by
+``KVM_GET_SUPPORTED_CPUID``, but it can be enabled if ``KVM_CAP_TSC_DEADLINE_TIMER``
+is present and the kernel has enabled in-kernel emulation of the local APIC.
+On newer versions, ``KVM_GET_SUPPORTED_CPUID`` does report the bit as available.
CPU topology
~~~~~~~~~~~~
--
2.49.0
On Mon, Mar 31, 2025, Paolo Bonzini wrote:
> TSC_DEADLINE is now advertised unconditionally by KVM_GET_SUPPORTED_CPUID,
> since commit 9be4ec35d668 ("KVM: x86: Advertise TSC_DEADLINE_TIMER in
> KVM_GET_SUPPORTED_CPUID", 2024-12-18). Adjust the documentation to
> reflect the new behavior.
>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
Sorry, at one point I even had this on my todo list for that series.
Reviewed-by: Sean Christopherson <seanjc@google.com>
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