ACK: [SRU][Q:linux-oracle][PATCH 0/1] oracle: set enable_virt_at_load default to false on kernels > 6.8

[Tim Whisonant]

On Thu, Jan 29, 2026 at 02:34:03PM -0300, Vinicius Peixoto wrote:
> BugLink: https://bugs.launchpad.net/bugs/2139360
> 
> [Impact]
> 
> OCI uses live migration to migrate VM instances from hosts to hosts.
> That feature is currently not possible if nested virtualisation is
> enabled. However, in commit b4886fab6fb62 ("KVM: Add a module param to
> allow enabling virtualization when KVM is loaded"), the
> enable_virt_at_load parameter was introduced for the KVM module, and was
> set to true by default, making it such that the kvm module sets the
> EFER.SVME bit at load time, rather than when a guest is started. This is
> a breaking change for the OCI live migration use case.
> 
> [Fix]
> 
> Change the default value of enable_virt_at_load to false in our Oracle
> kernels > 6.8 in order to support the live migration use case. This is
> implemented as a sauce patch within the Oracle kernels only, since the
> justification is specific to the OCI use case and unlikely to be
> accepted by upstream.
> 
> [Test plan]
> 
> Oracle has validated this fix on their side using packages provided by
> Phil Cox in this PPA (thanks Phil!):
> https://launchpad.net/~philcox/+archive/ubuntu/oracle-sf00417471-disable-enable-virt-at-load
> 
> [Where problems could occur]
> 
> This change is relatively harmless, with the only downside (currently,
> on the 6.17 Oracle kernel) being that TDX requires
> enable_virt_at_load=true since fcdbdf63431c9 ("KVM: VMX: Initialize TDX
> during KVM module load"); however, this limitation is not currently
> relevant to the OCI use case.
> 
> [Other info]
> SF #00417471
> 
> Philip Cox (1):
>   UBUNTU: SAUCE: kvm: set `enable_virt_at_load` default to false
> 
>  virt/kvm/kvm_main.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> -- 
> 2.51.0
> 
> 

Acked-by: Tim Whisonant <tim.whisonant at canonical.com>