Re: [PATCH wireless-next v4 08/21] wifi: nl80211/cfg80211: pack SMD dynamic context along with frame

[Allen Ye <Allen.Ye@mediatek.com>]

On Fri, 2026-11-06 at 13:28 +0530, Pooventhiran G wrote:

Hi Pooventhiran,

A question on how the context is collected here.

> While packing the received management frame in nl80211_send_mgmt() to
> send to userspace, nest the SMD dynamic context along with the frame
> message.

On MediaTek chipsets (mt76), the dynamic context is kept in FW/HW, so
the driver has to fetch it from the firmware with an MCU command. This
means the driver has to hold the ST request frame until the firmware
replies with an event, and only then pass the frame up. Holding RX
frames in the driver is the problematic part: the frame has to be kept
outside the normal RX path, kept in order with the frames that follow
it, and handled if the firmware reply is delayed or never arrives.

1. With the context attached to the frame, how it gets collected
depends on each vendor driver's own implementation (on mt76, this may
mean holding the frame in the driver as described above). If userspace
instead queried it via GET_SMD_CTX / SMD_CTX_EVENT for ST preparation
and ST execution via the current AP MLD, as it already does for ST
execution via the target AP MLD, the flow would be the same for every
driver, regardless of where the context is kept. Would that be
acceptable?

2. If not, could the frame-attached context be optional (e.g. behind a
capability flag), with userspace falling back to GET_SMD_CTX?

Thanks,
Allen