[PATCH v3 0/3] x86/vmware: Clean up the hypercall code

[Zack Rusin <zack.rusin@broadcom.com>]

Move VMware hypercall assembly out of vmware.h and select the
low-bandwidth backend with a static call, following Linus's request:
https://lore.kernel.org/all/CAHk-=wivx7pi+h+hGmvNFAJm6StQLiQ-b8DdsE5J=LMOWae8Ng@mail.gmail.com/

Patch 1 moves the high-bandwidth helpers out of line and removes the
redundant vmwgfx caller annotations. Patch 2 uses input and result
structures for the four low-bandwidth backends, selects the backend
during VMware platform setup, and removes the early dispatcher. Patch 3
retires the unused VMware feature bits.

The caller API is unchanged. The I/O-port backdoor remains the initial
target for early DMI probing. Modules use the exported high-bandwidth
helpers and static-call trampoline; the static-call key stays private.

This v3 replaces patch 1 of Alexey's v2:
https://lore.kernel.org/all/20260309235250.2611115-1-alexey.makhalov@broadcom.com/
Its panic logging patches and steal-time fix were reposted separately:
https://lore.kernel.org/r/cover.1790014793.git.zack.rusin@broadcom.com
https://lore.kernel.org/r/20260929040256.543767-1-zack.rusin@broadcom.com

It is based on tip's x86/urgent branch, which has the i386
high-bandwidth fix this series builds on: e0e022004bbe ("x86/vmware:
Fix i386 high-bandwidth hypercall arguments").

Please route this through tip. As the vmwgfx maintainer, I agree that
its small annotation removal should go through tip with the assembly
move. DRM maintainers and dri-devel are copied. I'll make sure there are
no conflicts in that code while the trees merge.

And yes, this code is a bit like me, meaning it gets on everyone's nerves
and likely looks awkward in shorts, so we're just trying to make the best
out of what a politician would call a less-than-ideal situation.

Changes since v2:
- Replace the ten-argument backend interface with input/result structures.
- Move the high-bandwidth assembly out of the header as well.
- Preserve all low-bandwidth outputs and the backend-specific %dx flags.
- Export the callable trampoline without exporting its key.
- Correct the ABI documentation and retire unused feature bits.
- Keep the backportable i386 fix in its separate posting.

Alexey Makhalov (1):
  x86/vmware: Route low-bandwidth hypercalls through a static call

Zack Rusin (2):
  x86/vmware: Move high-bandwidth hypercalls out of line
  x86/cpufeatures: Remove unused VMware hypercall feature bits

 arch/x86/include/asm/cpufeatures.h  |   4 +-
 arch/x86/include/asm/vmware.h       | 371 +++++++++++-----------------
 arch/x86/kernel/cpu/vmware.c        | 299 +++++++++++++++-------
 drivers/gpu/drm/vmwgfx/vmwgfx_msg.c |   3 -
 4 files changed, 351 insertions(+), 326 deletions(-)


base-commit: e0e022004bbedc7caf1c18770980eb5372019189