[JAMMY][SRU][PATCH 0/4] Backport support to tolerate ZSTD compressed firmware files

[Dimitri John Ledkov]

On Wed, 26 Jul 2023 at 13:42, Tim Gardner <tim.gardner at canonical.com> wrote:
>
> On 7/25/23 3:15 PM, Dimitri John Ledkov wrote:
> > [ Impact ]
> >
> >   * To ensure reliable dist-upgrades in case of partial upgrades or
> >     upgrade failures, it is desirable for LTS GA kernel to support
> >     features that next-LTS GA kernel will rely on.
> >
> >   * Specifically it is being discussed to switch linux-firmware to ZSTD
> >     compressed one
> >
> >   * To ensure that failed dist-upgrades can still boot after-partial
> >     upgrade it is desirable to suppport zstd compressed firmware
> >
> > [ Test Plan ]
> >
> >   * Boot new build of GA linux kernel with
> >     CONFIG_FW_LOADER_COMPRESS_ZSTD
> >
> >   * Check that existing firmware files loaded on a given machine can be
> >     compressed with zstd and still loaded by this kernel
> >
> >   * Check that depmod / initramfs-tools all support .zst compressed
> >     firmware
> >
> > [ Where problems could occur ]
> >
> >   * Once this is inroduced in jammy-GA kernel it may cripple into
> >     focal-hwe kernels too, and people may start relying on this feature
> >     despite not universally supported by all other focal kernels. This
> >     should be trivial to catch in SRUs for example, do not accept SRUs
> >     of firmwares that ship themselves as .zst in Jammy and lower.
> >
> > [ Other Info ]
> >
> >   * See
> >     https://lists.ubuntu.com/archives/ubuntu-devel/2023-July/042652.html
> >
> > Dimitri John Ledkov (2):
> >    UBUNTU: SAUCE: Backport ZSTD-compressed firmware files to old ZSTD API
> >    UBUNTU: [Config] Enable FW_LOADER_COMPRESS_ZSTD by default
> >
> > Randy Dunlap (1):
> >    firmware_loader: EXTRA_FIRMWARE does not support compressed files
> >
> > Takashi Iwai (1):
> >    firmware: Add the support for ZSTD-compressed firmware files
> >
> >   debian.master/config/annotations     |  3 ++
> >   drivers/base/firmware_loader/Kconfig | 27 ++++++++--
> >   drivers/base/firmware_loader/main.c  | 76 ++++++++++++++++++++++++++--
> >   3 files changed, 98 insertions(+), 8 deletions(-)
> >
>
> Shouldn't you merge 'UBUNTU: SAUCE: Backport ZSTD-compressed firmware
> files to old ZSTD API' into ' firmware: Add the support for
> ZSTD-compressed firmware files' and call it  a backport ? Otherwise
> you've introduced a commit that won't compile.

Correct if those two commits are squished together, it becomes a
backport. However, to me it seems more clear to present my work like
this, at least for the review.
Or do people routinely interdiff the patch with upstream one to see
the backport diff progmatically?

-- 
okurrr,

Dimitri