From: Jiri Denemark <jdenemar@redhat.com>

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
---
 NEWS.rst | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/NEWS.rst b/NEWS.rst
index 07f539f996..53c2c205a3 100644
--- a/NEWS.rst
+++ b/NEWS.rst
@@ -54,6 +54,14 @@ v12.5.0 (2026-07-01)
     specifying additional arguments to it, via ``argv``
     attribute.
 
+  * Introduce VIR_CONNECT_GET_DOMAIN_CAPABILITIES_SUPPORTED_CPU_FEATURES flag
+
+    Some CPU features may be enabled explicitly, but should not automatically
+    become part of a host-model CPU and thus are not normally visible in domain
+    capabilities. Users can now request such features to be shown in the
+    host-model CPU in domain capabilities using the new flag. It is exposed as
+    ``--supported-cpu-features`` option for ``virsh domcapabilities``.
+
 * **Bug fixes**
 
   * Ensure proper shutdown ordering of ``virtlogd`` and ``virtlockd``
@@ -78,6 +86,18 @@ v12.5.0 (2026-07-01)
     not properly initializing an agent to crashing when the agent
     socket cannot be opened.
 
+  * Fix domain capabilities on AMD CPUs
+
+    QEMU 10.1 and newer does not automatically enable features from
+    arch-capabilities MSR on AMD CPUs as they are specific for Intel CPUs and
+    KVM is just emulating them on AMD. But advertising them on AMD CPUs can
+    cause Windows guest OS to crash so they are hidden by default now. But the
+    features are still supported and can be enabled explicitly, for example,
+    when migrating existing domains. Libvirt now detects this scenario and
+    properly shows the affected features as enabled in domain capabilities when
+    requested by VIR_CONNECT_GET_DOMAIN_CAPABILITIES_SUPPORTED_CPU_FEATURES
+    flag.
+
 
 v12.4.0 (2026-06-01)
 ====================
-- 
2.54.0

On Wed, Jul 01, 2026 at 11:21:11 +0200, Jiri Denemark via Devel wrote:
> From: Jiri Denemark <jdenemar@redhat.com>
> 
> Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
> ---
>  NEWS.rst | 20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
> 
> diff --git a/NEWS.rst b/NEWS.rst
> index 07f539f996..53c2c205a3 100644
> --- a/NEWS.rst
> +++ b/NEWS.rst
> @@ -54,6 +54,14 @@ v12.5.0 (2026-07-01)
>      specifying additional arguments to it, via ``argv``
>      attribute.
>  
> +  * Introduce VIR_CONNECT_GET_DOMAIN_CAPABILITIES_SUPPORTED_CPU_FEATURES flag

Mark the flag as code via '``'

> +
> +    Some CPU features may be enabled explicitly, but should not automatically
> +    become part of a host-model CPU and thus are not normally visible in domain
> +    capabilities. Users can now request such features to be shown in the
> +    host-model CPU in domain capabilities using the new flag. It is exposed as
> +    ``--supported-cpu-features`` option for ``virsh domcapabilities``.
> +
>  * **Bug fixes**
>  
>    * Ensure proper shutdown ordering of ``virtlogd`` and ``virtlockd``
> @@ -78,6 +86,18 @@ v12.5.0 (2026-07-01)
>      not properly initializing an agent to crashing when the agent
>      socket cannot be opened.
>  
> +  * Fix domain capabilities on AMD CPUs
> +
> +    QEMU 10.1 and newer does not automatically enable features from
> +    arch-capabilities MSR on AMD CPUs as they are specific for Intel CPUs and
> +    KVM is just emulating them on AMD. But advertising them on AMD CPUs can
> +    cause Windows guest OS to crash so they are hidden by default now. But the
> +    features are still supported and can be enabled explicitly, for example,
> +    when migrating existing domains. Libvirt now detects this scenario and
> +    properly shows the affected features as enabled in domain capabilities when
> +    requested by VIR_CONNECT_GET_DOMAIN_CAPABILITIES_SUPPORTED_CPU_FEATURES

Mark the flag as code

> +    flag.
> +
>  
>  v12.4.0 (2026-06-01)
>  ====================
> -- 
> 2.54.0
> 

Reviewed-by: Peter Krempa <pkrempa@redhat.com>