Am 23. November 2024 03:08:02 MEZ schrieb Andre Przywara <andre.przyw...@arm.com>: >On Fri, 15 Nov 2024 07:21:53 -0700 >Simon Glass <s...@chromium.org> wrote: > >Hi Simon, Tom, Heinrich, > >sorry for the delay, I was away. > >> On Wed, 13 Nov 2024 at 10:50, Tom Rini <tr...@konsulko.com> wrote: >> > >> > On Wed, Nov 13, 2024 at 08:09:33AM -0700, Simon Glass wrote: >> > >> > > This causes problems with the boot order, so drop it until we can figure >> > > out a better way to know when bootmgr should be used. >> > > >> > > Link: >> > > https://lore.kernel.org/u-boot/20241112171205.4e805...@donnerap.manchester.arm.com/ >> > > >> > > Signed-off-by: Simon Glass <s...@chromium.org> >> > >> > I would really prefer a short summary of the contents of the link in the >> > commit message. I'm not NAK'ing the patch as-is, but it would be helpful >> > when revisiting this if there was a short explanation of the problem to >> > solve here and not just "problems with the boot order". Thanks. >> >> The summary is that sunxi supports FEL (USB boot) but bootmgr is not >> aware of it, so boots the OS instead. > >So that's not the problem: FEL is working fine, since it's marked as >global, same as efi_bootmgr, but with a lower order number. The problem >is that the higher priority non-global methods (scripts) are "ignored". > >So this is the list without this patch: >Order Seq Name Description >----- --- ------------------ ------------------ > 0 0 extlinux extlinux > glob 1 fel FEL > 2 2 script script > glob 3 efi_mgr EFI bootmgr flow > 4 4 efi EFI > 5 5 pxe PXE > glob 6 vbe_simple vbe-simple >----- --- ------------------ ------------------ > >The sequence looks roughly alright, only that it's not the actual >order, since "glob" takes precedence. So the actual order is: >fel -> efi_mgr -> vbe_simple -> extlinux -> script -> efi -> pxe >And that puts efi_mgr before extlinux and script, which is not what we >want, because efi_mgr finds bootaa64.efi *somewhere* (eMMC or SD card or >USB stick) and uses that, even when there is a tailored boot.scr or >extlinux.conf on the *boot media* which should be higher priority. >"fel" being first is fine, since it's *only* triggered if someone >deliberately uploaded a boot script via USB: in this case they surely >want to execute exactly that. > >So I think the underlying problem is the "glob" tag for efi_mgr PLUS >the fact that it scans all media for bootaa64.efi files. I think it >would be fine if efi_mgr would just consider EFI boot order variables, >and would ignore any "removable media" default files (bootaa64.efi). >The "efi" bootmeth does the scanning as well, and it's fine there, >since it's lower priority, so we can still boot EFI systems. > >I guess it would make sense if an installer on an USB stick should boot >even if there is something on the eMMC, for instance. But we want to >control that, and we can't, because the order is ignored due to the >"glob" flag. > >So while I agree that disabling efi_bootmgr sounds like a hack, it >solves the problem quite elegantly: We keep the (current) boot order, >which prioritises scripts over EFI, but still retain EFI. If people >want EFI first, they can change the order in the environment (I think?). > >Without that patch there is quite a regression for users, because >suddenly any bootaa64.efi files *somewhere* would be booted first, and >there is no way to turn that off. > >This has bitten me actually: for development I put a custom boot.scr on >an SD card which loads a kernel+DTB via TFTP from my box. And I want >that to be first, despite there being a proper EFI setup on the eMMC or >USB drive. > >So I hope that clears that up. I am not a big fan of that patch, but I >would like sunxi to be converted, and Simon seemed to be eager to do >this as well, so in the interest of not blocking this, I am fine with >that.
Disabling EFI will break booting for users that rely on it (like me). > >Cheers, >Andre Yes, the introduction of boot standard changed the boot order and specifically deprioritizing scripts is unexpected. The priority sequence used to be scripts extlinux efi pxe bootmeth_efimgr always running before scripts be fixed. bootmeth_efi should be removed from the code base as redundant. Best regards Heinrich
