[PATCH v5 00/12] efi_loader: more tightly integrate UEFI disks to driver model

[AKASHI Takahiro]

On Mon, Apr 25, 2022 at 10:43:44PM +0200, Heinrich Schuchardt wrote:
> On 4/19/22 03:05, AKASHI Takahiro wrote:
> > With this patch set[1] applied, UEFI subsystem maintains a list of its
> > disk objects dynamically at runtime based on block device's probing.
> > (See "issues" and "prerequisite" below.)
> > 
> > [1] https://github.com/t-akashi/u-boot/tree/efi/dm_disk
> > 
> > For instance,
> > => dm tree
> >   Class     Index  Probed  Driver                Name
> > -----------------------------------------------------------
> >   root          0  [ + ]   root_driver           root_driver
> >   ...
> >   pci           0  [ + ]   pci_generic_ecam      |-- pcie at 10000000
> >   ...
> >   ahci          0  [   ]   ahci_pci              |   |-- ahci_pci
> >   scsi          0  [   ]   ahci_scsi             |   |   `-- ahci_scsi
> >   usb           0  [   ]   xhci_pci              |   `-- xhci_pci
> >   ...
> > => efi devices
> > Missing RNG device for EFI_RNG_PROTOCOL
> > No EFI system partition
> > Unable to find TPMv2 device
> > Device           Device Path
> > ================ ====================
> > 000000013eee88d0 /VenHw(..)
> > 000000013ffeb798 /VenHw(..)/Uart(0,0,D,D)
> > 000000013eeeb810 /VenHw(..)/MAC(525252525252,1)
> > => scsi rescan
> 
> 
> With the series binding block devices after initializing the UEFI
> sub-system works fine. Also unbinding is reflected in the EFI devices.
> 
> But this series breaks UEFI compliance.

I don't think so.

> All block devices must be probed
> before booting.

This (not enumerating all the devices) is also true even before my patch.

> Without this GRUB will not be able to read the boot
> partition with vmlinuz and initrd.

I'm not sure what you expect here, but
is it enough to define "preboot" variables with any number of
enumerating commands, like "scsi rescan", "usb start" and so on?

# Again, this method can also be applied even without my patch.

-Takahiro Akashi

> Will you provide the missing patch?
> 
> Best regards
> 
> Heinrich