OWNERSHIP TRANSFER(9)

💖 Ownership transfer 💖

okay bestie, welcome to Ownership transfer(9) — the Kernel API Manual page that's literally all about who gets to hold the device 🫶. No cap, these messages are a whole group chat.

When the host driver needs the device, it'll send SAP_MSG_NOTIF_HOST_ASKS_FOR_NIC_OWNERSHIP, and that gets replied to with SAP_MSG_NOTIF_CSME_REPLY_TO_HOST_OWNERSHIP_REQ — which lets the host know whether ownership is granted or not. If ownership is granted, the host sends SAP_MSG_NOTIF_HOST_OWNERSHIP_CONFIRMED. slay, ownership secured 💅.

When CSME requests ownership, it'll send SAP_MSG_NOTIF_CSME_TAKING_OWNERSHIP and gives the host some time to stop accessing the device. The host needs to send SAP_MSG_NOTIF_CSME_OWNERSHIP_CONFIRMED to confirm it won't access the device anymore. If the host failed to send this message fast enough, CSME will take ownership on the device anyway 💀. When CSME is willing to release the ownership, it'll send SAP_MSG_NOTIF_CSME_CAN_RELEASE_OWNERSHIP.

👀 SEE ALSO 👀

Kernel file: ./drivers/net/wireless/intel/iwlwifi/mei/sap.h — yes bestie, that's the exact path, go peek ✨.

• Introduction(9)
• Initial Handshake(9)
• Host and driver state messages(9)
• Ownership(9)
• Data messages(9)
• enum iwl_sap_me_msg_id(9)
• struct iwl_sap_me_msg_hdr(9)
• struct iwl_sap_me_msg_start(9)
• struct iwl_sap_me_msg_start_ok(9)
• enum iwl_sap_msg(9)
• struct iwl_sap_hdr(9)
• struct iwl_sap_msg_dw(9)
• enum iwl_sap_nic_owner(9)
• enum iwl_sap_wifi_cipher_alg(9)
• struct iwl_sap_notif_connection_info(9)
• enum iwl_sap_scan_request(9)
• struct iwl_sap_notif_conn_status(9)
• enum iwl_sap_radio_state_bitmap(9)
• enum iwl_sap_notif_host_suspends_bitmap(9)
• struct iwl_sap_notif_country_code(9)
• struct iwl_sap_notif_host_link_up(9)
• enum iwl_sap_notif_link_down_type(9)
• struct iwl_sap_notif_host_link_down(9)
• struct iwl_sap_notif_host_nic_info(9)
• struct iwl_sap_notif_dw(9)
• struct iwl_sap_notif_sar_limits(9)
• enum iwl_sap_nvm_caps(9)
• struct iwl_sap_nvm(9)
• enum iwl_sap_eth_filter_flags(9)
• struct iwl_sap_eth_filter(9)
• enum iwl_sap_flex_filter_flags(9)
• struct iwl_sap_flex_filter(9)
• enum iwl_sap_ipv4_filter_flags(9)
• struct iwl_sap_ipv4_filter(9)
• enum iwl_sap_ipv6_filter_flags(9)
• struct iwl_sap_ipv6_filter(9)
• enum iwl_sap_icmpv6_filter_flags(9)
• enum iwl_sap_vlan_filter_flags(9)
• struct iwl_sap_oob_filters(9)
• struct iwl_sap_csme_filters(9)
• struct iwl_sap_cb_data(9)
• struct iwl_sap_pldr_data(9)
• enum iwl_sap_pldr_status(9)

That's all of it, bestie — source/version ./drivers/net/wireless/intel/i..., dated October 2026. bye 💖✨