On Thu, Sep 08, 2022 at 03:30:15PM +0200, Ard Biesheuvel wrote: > When GRUB runs on top of EFI firmware, it only has access to block and > network device abstractions exposed by the firmware, and it is up to the > firmware to quiesce the underlying hardware when exiting boot services > and handing over to the OS. > > This is especially important for network devices, to prevent incoming > packets from being DMA'd straight into memory after the OS has taken > over but before it has managed to reconfigure the network hardware. > > GRUB handles this by means of the grub_net_fini_hw() preboot hook, which > is executed before calling into the booted image. This means that all > network devices disappear or become inoperable before the EFI stub > executes on EFI targeted builds. This is problematic as it prevents the > EFI stub from calling back into GRUB provided protocols such as > LoadFile2 for the initrd, which we will provide in a subsequent patch. > > So add a flag that indicates to the network core that EFI network > devices should not be closed when grub_net_fini_hw() is called. > > Signed-off-by: Ard Biesheuvel <a...@kernel.org> > Reviewed-by: Heinrich Schuchardt <heinrich.schucha...@canonical.com>
Reviewed-by: Daniel Kiper <daniel.ki...@oracle.com> Daniel _______________________________________________ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel
