Heinrich,
On Fri, Jan 03, 2020 at 01:17:05AM +0100, Heinrich Schuchardt wrote:
On 4/19/19 5:22 AM, AKASHI Takahiro wrote:
There are several reasons that I want to rework/refactor bootefi command as well as bootmgr:
Some previous commits on bootefi.c have made the code complicated and a bit hard to understand.
do_bootefi_exec() would better be implemented using load_image() along with start_image() to be aligned with UEFI interfaces.
Contrary to the other part, efi_selftest part of the code is unusual in terms of loading/execution path in do_bootefi().
When we will support "secure boot" in the future, EFI Boot Manager is expected to be invoked as a standalone command without any arguments to mitigate security surfaces.
In this patch set, Patch#1 to #7 are preparatory patches for patch#8. Patch#8 is a core part of reworking. Patch#9 is for standalone boot manager.
# Please note that some patches, say patch#2 and #3, can be combined into one # but I intentionally keep them separated to clarify my intentions of changes.
Issues:
- It would be better off to change the semantics of efi_dp_from_name().
no chance to free loaded_image_info->load_options. (see patch #8)
-Takahiro Akashi
Hello Takahiro,
with the `efidebug boot add` command we can define load options for the BootXXXX variables.
But in do_efibootmgr() we call do_bootefi_exec() which calls set_load_options() and passes the value of environment variable bootargs as load options or if the variable is not set an empty string.
Here is an example console output:
=> setenv bootargs This is a value from bootargs => efidebug boot add 0000 hello scsi 0:1 helloworld.efi 'This is a value from efidebug' => efidebug boot order 0000 => bootefi bootmgr Booting: hello Hello, world! Running on UEFI 2.8 Have SMBIOS table Have device tree Load options: This is a value from bootargs ## Application terminated, r = 0
Now the same after deleting variable bootargs:
=> setenv bootargs => bootefi bootmgr Booting: hello Hello, world! Running on UEFI 2.8 Have SMBIOS table Have device tree Load options: <none> ## Application terminated, r = 0 =>
Yeah, this is not what I intended.
What behavior would you expect:
a) if the boot option has a load options value, b) if the boot option has no load options value?
One solution would be to define that bootargs is always ignored if the boot manager is used.
I agree. Basically, "bootargs" is only for "bootefi <addr>" command, while "BootXXXX" should work in the exact same way as the UEFI specification defines.
Thanks, -Takahiro Akashi
Best regards
Heinrich