* The Sysctls experimental feature has been promoted to beta (enabled by default via the `Sysctls` feature flag). PodSecurityPolicy and Pod objects now have fields for specifying and controlling sysctls. Alpha sysctl annotations will be ignored by 1.11+ kubelets. All alpha sysctl annotations in existing deployments must be converted to API fields to be effective. ([#6371](https://github.com...

* The `spec.SecurityContext.Sysctls` field is now dropped during creation of `Pod` objects unless the `Sysctls` feature gate is enabled. ([#72752](https://github.com/kubernetes/kubernetes/pull/72752), [@rajathagasthya](https://github.com/rajathagasthya))
    * The `spec.AllowedUnsafeSysctls` and `spec.ForbiddenSysctls` fields are now dropped during creation of `PodSecurityPolicy` objects unless the `Sysctls` feature gate is enabled.

  and “net.ipv4.tcp_keepalive_probes“ sysctl by default; Pod Security Admission
  allows this sysctl in `v1.29+` versions of the baseline and restricted policies. ([#121240](https://github.com/kubernetes/kubernetes/pull/121240), [@HirazawaUi](https://github.com/HirazawaUi))
- `kubelet` now allows pods to use the `net.ipv4.tcp_keepalive_time` sysctl by default

- Introduced the flag `--ipvs-strict-arp` to configure stricter ARP sysctls, defaulting to false to preserve existing behaviors. This was enabled by default in 1.13.0, which impacted a few CNI plugins. ([#75295](https://github.com/kubernetes/kubernetes/pull/75295), [@lbernail](https://github.com/lbernail))

- Pod SecurityContext sysctls name parameter for update requests where the existing object's sysctl contains slashes and kubelet sysctl whitelist support contains slashes. ([#102393](https://github.com/kubernetes/kubernetes/pull/102393), [@mengjiao-liu](https://github.com/mengjiao-liu)) [SIG Apps, Auth, Node, Storage and Testing]...

pkg syscall (darwin-amd64), func SetBpfDatalink //deprecated
pkg syscall (darwin-amd64), func SetBpfHeadercmpl //deprecated
pkg syscall (darwin-amd64), func SetBpfImmediate //deprecated
pkg syscall (darwin-amd64), func SetBpfInterface //deprecated
pkg syscall (darwin-amd64), func SetBpfPromisc //deprecated
pkg syscall (darwin-amd64), func SetBpfTimeout //deprecated
pkg syscall (darwin-amd64), func StringSlicePtr //deprecated

- Pods were allowed to use the `net.ipv4.tcp_rmem` and `net.ipv4.tcp_wmem` sysctl by default
  when the kernel version was 4.15 or higher. With the kernel 4.15 the sysctl became namespaced.

  
  When the feature gate is enabled, kubelet ignores errors that happens during setting the following sysctl values: `vm.overcommit_memory`, `vm.panic_on_oom`, `kernel.panic`, `kernel.panic_on_oops`, `kernel.keys.root_maxkeys`, `kernel.keys.root_maxbytes`. (These sysctl values for the host, not for the containers)
  
  kubelet also ignores an error during opening `/dev/kmsg`.

- Kubelet allows pods to use the `net.ipv4.ip_local_reserved_ports` sysctl by default and the minimal kernel version is 3.16; Pod Security admission allows this sysctl in v1.27+ versions of the baseline and restricted policies. ([#115374](https://github.com/kubernetes/kubernetes/pull/115374), [@pacoxu](https://github.com/pacoxu)) [SIG Auth, Network and Node]

- Pod SecurityContext and PodSecurityPolicy supports slash as sysctl separator. ([#106834](https://github.com/kubernetes/kubernetes/pull/106834), [@mengjiao-liu](https://github.com/mengjiao-liu)) [SIG Apps, Architecture, Auth, Node, Security and Testing]