[XEN PATCH 0/2] Use streaming decompression for ZSTD kernels

[Rafaël Kooi <rafael_andreas@xxxxxxxxxxx>]

I've attempted to get Xen to boot Arch Linux as a unified EFI binary.
Using https://xenbits.xen.org/docs/unstable/misc/efi.html as my source
of information, I've been able to build a unified binary. When trying to
boot the kernel Xen complains that the stream is corrupt
("ZSTD-compressed data is corrupt"). I've been able to reproduce the
issue locally in user-mode, and confirmed that the issue is also present
in the latest ZSTD version.

Using streaming decompression the kernel gets unpacked properly and the
output is the same as if doing `cat kernel.zst | unzstd > bzImage`.

A problem I ran into was that adding book keeping to decompress.c would
result in either a .data section being added or a .bss.* section. The
linker would complain about this. And since I am not familiar with this
code, and why it is this way, I opted to add a user-pointer to the
internal decompression API.

Rafaël Kooi (2):
  xen/decompress: Add a user pointer for book keeping in the callbacks
  x86/Dom0: Use streaming decompression for ZSTD compressed kernels

 xen/common/bunzip2.c         | 23 ++++++++++++----------
 xen/common/decompress.c      | 37 ++++++++++++++++++++++++++++++------
 xen/common/unlz4.c           | 15 ++++++++-------
 xen/common/unlzma.c          | 30 +++++++++++++++++------------
 xen/common/unlzo.c           | 13 +++++++------
 xen/common/unxz.c            | 11 ++++++-----
 xen/common/unzstd.c          | 13 +++++++------
 xen/include/xen/decompress.h | 10 +++++++---
 8 files changed, 97 insertions(+), 55 deletions(-)

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2.40.0