[Buildroot] [PATCH v2] imx/genimage: Place the rootfs at a proper offset when BR2_LINUX_KERNEL_INSTALL_TARGET=y

[Thomas Petazzoni]

On Sat, 13 Nov 2021 18:42:45 -0300
Fabio Estevam <festevam at gmail.com> wrote:

> Currently, when BR2_LINUX_KERNEL_INSTALL_TARGET=y is selected, issuing
> a "saveenv" command in the U-Boot prompt may lead to rootfs corruption.
> 
> When BR2_LINUX_KERNEL_INSTALL_TARGET is not selected, then
> board/freescale/common/imx/genimage.cfg.template is used as per the logic
> inside board/freescale/common/imx/post-image.sh.
> 
> board/freescale/common/imx/genimage.cfg.template correctly puts the
> rootfs at a safe offset.
> 
> With BR2_LINUX_KERNEL_INSTALL_TARGET=y, then
> board/freescale/common/imx/genimage.cfg.template_no_boot_part or
> board/freescale/common/imx/genimage.cfg.template_no_boot_part_spl
> are used and no offset to the rootfs is given, which may cause U-Boot
> environment area to write into the rootfs area, causing the rootfs
> corruption.
> 
> Avoid this problem by placing the rootfs at an 8MB offset, just like
> it is done in board/freescale/common/imx/genimage.cfg.
> 
> Tested on a imx6qp-wandboard and also on a custom imx6ull based board.
> 
> "saveenv" does not corrupt the rootfs anymore after this change.
> 
> Signed-off-by: Fabio Estevam <festevam at gmail.com>
> ---
> Changes since v1:
> - Improve commit log (Yann)

Applied to master, thanks.

Thomas
-- 
Thomas Petazzoni, CTO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com