Re: [PATCH 0/2] arm64: Support HP Envy X2

[Leif Lindholm]

On Wed, Nov 28, 2018 at 03:31:05PM +0100, Alexander Graf wrote:
> I got a new toy this week: An HP Envy X2 system. This is one of those shiny
> new Qualcomm Snapdragon based Windows tablet/notebook hybrid things.
> 
> While running Windows on those is actually not a terribly bad experience now
> that WSL is out, I would like to see Linux run on those as well in the future.
> 
> Unfortunately as far as I'm aware so far nobody was able to run self built
> binaries on the built-in UEFI version.
> 
> Turns out, it's a problem with aligning the start of the header to 4k. Once
> we do that, binaries can be loaded just fine and run.
> 
> So to maintain compatibility with that device, this patch set just bumps the
> header alignment to 4K always on arm64-efi. This shouldn't hurt too much for
> not affected targets and allows us to have a single grub binary that can then
> chain load Linux properly.

After further conversations with HP, they appear to be doing this in
order to be able to enforce no-execute properties on the image
header. Also, it seems Visual Studio always does this.

So if you could tweak your set to refer to this aspect rather than a
specific platform, drop mentions of HP Envy from other than the cover
letter, and use EFI_PAGE_SIZE rather than 4096 in 2/2, I think this
change is the right thing to do.

We're going to move to this being the default for AArch64 in EDK2:
https://lists.01.org/pipermail/edk2-devel/2018-December/033708.html

(That the Envy X2 shouldn't hang silently on encountering a
non-4K-aligned code offset is a different story, and an ongoing
conversation.)

/
    Leif

> 
> Alex
> 
> Alexander Graf (2):
>   mkimage: Simplify header size logic
>   mkimage: arm64-efi: Align first section to page
> 
>  util/mkimage.c | 8 +++-----
>  1 file changed, 3 insertions(+), 5 deletions(-)
> 
> -- 
> 2.19.0
>