[PATCH] commands: oftree: kill oftree -f

Alexander Kurz akurz at blala.de
Mon Jun 11 11:35:48 PDT 2018

Hi Sascha,
On Mon, 11 Jun 2018, Sascha Hauer wrote:

> Being able to free the live device tree seemed like a good idea in the
> early days of device tree support when the first boards were brought up.
> It turned out to be illusory that noone stores pointers to the live tree
> which become invalid when oftree -f is executed. Enough people stumbled
> upon crashed boards with this option, so remove it finally.

oftree -f is still in use in boot scripts, e.g. for the kindle-mx50,
and at least one other board.
The usecase for the kindle-mx50 is
* DT based barebox
* ATAGs dependent antiquated, non upgradeable kernel

start_linux() (arch/arm/lib32/armlinux.c) wont do setup_tags() if there
still exists an oftree.
If there is an alternative way to make boot issue 
ATAGs, removing the -f option would be fine.

May I mention an old (rejected) proposal about this issue

Also note: it's still in Documentation/user/devicetree.rst

Regards, Alexander

More information about the barebox mailing list