Hello Rob, On Fri, 10 May 2024 11:44:49 -0500 Rob Herring <robh@xxxxxxxxxx> wrote: > On Fri, May 10, 2024 at 09:10:36AM +0200, Luca Ceresoli wrote: [...] > > Overall approach > > ================ > > > > Device tree overlays appear as the most natural solution to support the > > addition and removal of devices from a running system. > > > > Several features are missing from the mainline Linux kernel in order to > > support this use case: > > > > 1. runtime (un)loading of device tree overlays is not supported > > Not true. Device specific applying of overlays has been supported > since we merged DT overlay support. What's not supported is a general > purpose interface to userspace to change any part of the DT at any point > in time. I think I should replace "supported" with "exposed [to user space]". In other words, there is no user of of_overlay_fdt_apply() / of_overlay_remove*() in mainline Linux, except in unittest. Would it be a correct rewording? > > 2. if enabled, overlay (un)loading exposes several bugs > > Hence why there is no general purpose interface. Absolutely. Best regards, Luca -- Luca Ceresoli, Bootlin Embedded Linux and Kernel engineering https://bootlin.com
