On Sat, 4 Apr 2020 at 12:50, Heinrich Schuchardt xypron.glpk@gmx.de wrote:
On 4/4/20 11:57 AM, François Ozog wrote:
Hi,
I instrumented boot on my Ubuntu 18.04 server right after systemd startup and caught an access to: /sys/firmware/efi/efivars/LoaderDevicePartUUID-4a67b082-0a4c-41cf-b6c7-440b29bb8c4f
Jeremy's patch 06f7d4a1618d ("efibc: Add EFI Bootloader Control module") introduced the variable though this change seems to be unrelated to the commit message. See efibc_set_variable() in drivers/firmware/efi/efibc.c.
@Jeremy, Ard Why is this variable written when CONFIG_EFI_BOOTLOADER_CONTROL=y? It seems not be related to the description of the customizing setting.
According to the UEFI spec the SetVariable() service is optional at run-time.
I have started work on implementing variable services at run-time in U-Boot. See https://lists.denx.de/pipermail/u-boot/2020-March/404441.html.
The whole EFI bootloader control thing predates my EFI maintainership. I did find some discussions around it, and it seems like Matt simply merged to put an end to the discussion, rather than because he was convinced it was a good idea.