Bug#916695: grub-efi-arm 2.02+dfsg1-9 fails to boot Debian Buster

[Leif Lindholm]

On Wed, Dec 19, 2018 at 12:15:02AM +0100, Heinrich Schuchardt wrote:
> I have reinstalled grub-efi-arm 2.02+dfsg1-9.
> 
> With my current U-Boot and a custom built the 4.18.20 kernel I am able
> to boot.
> 
> The stock Debian kernel does not boot.
> 
> What it takes is a U-Boot v2018.11 with these additional patches:
> 
> * Revert "efi_loader: remove efi_exit_caches()"
> * efi_loader: Ensure memory allocations are page aligned
> * lib: crc32: mark static variable as __efi_runtime_data
>   (not relevant for Tinker Board)
> 
> and a kernel with Ard's patch
> 
> 43b2ceb0d4e0147b114cb1d0112a988cbb81ecbc
> efi/arm: Revert deferred unmap of early memmap mapping

Upstream commit 33412b8673135b18ea42beb7f5117ed0091798b6.

> This patch is available since Linux v4.19.6.

4.19.9-1 is now in Sid, and I'm told that should make it across
soon-ish. Ultimately, 

As part of this investigation, Heinrich did encounter (and address)
another issue introduced by the same changeset (which would at least
theoretically also affect arm64 since the first grub port):
https://lists.gnu.org/archive/html/grub-devel/2018-12/msg00042.html

I'll request that that patch gets pushed, but it does already have
maintainer Reviewed-by: (as well as mine).

Many thanks to Heinrich for excellent debugging.

/
    Leif