RE: [PATCH v2 0/4] Add new headers for Hyper-V Dom0

Michael Kelley
2024-11-11T04:13:01Z

From: Nuno Das Neves <nunodasneves@linux.microsoft.com> Sent: Thursday, November 7, 2024 2:32 PM
>
> To support Hyper-V Dom0 (aka Linux as root partition), many new
> definitions are required.

Using "dom0" terminology here and in the Subject: line is likely to
be confusing to folks who aren't intimately involved in Hyper-V work.
Previous Linux kernel commit messages and code for running in the
Hyper-V root partition use "root partition" terminology, and I couldn't
find "dom0" having been used before. "root partition" would be more
consistent, and it also matches the public documentation for Hyper-V.
"dom0" is Xen specific terminology, and having it show up in Hyper-V
patches would be confusing for the casual reader. I know "dom0" has
been used internally at Microsoft as shorthand for "Hyper-V root
partition", but it's probably best to completely avoid such shorthand
in public Linux kernel patches and code.

Just my $.02 ....

>
> The plan going forward is to directly import definitions from
> Hyper-V code without waiting for them to land in the TLFS document.
> This is a quicker and more maintainable way to import definitions,
> and is a step toward the eventual goal of exporting headers directly
> from Hyper-V for use in Linux.
>
> This patch series introduces new headers (hvhdk.h, hvgdk.h, etc,
> see patch #3) derived directly from Hyper-V code. hyperv-tlfs.h is
> replaced with hvhdk.h (which includes the other new headers)
> everywhere.
>
> No functional change is expected.
>
> Summary:
> Patch 1-2: Minor cleanup patches
> Patch 3: Add the new headers (hvhdk.h, etc..) in include/hyperv/
> Patch 4: Switch to the new headers
>
> Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
> ---
> Changelog:
> v2:
> - Rework the series to simply use the new headers everywhere
> instead of fiddling around to keep hyperv-tlfs.h used in some
> places, suggested by Michael Kelley and Easwar Hariharan

Thanks! That should be simpler all around.

Michael

> - Fix compilation errors with some configs by adding missing
> definitions and changing some names, thanks to Simon Horman for
> catching those
> - Add additional definitions to the new headers to support them now
> replacing hyperv-tlfs.h everywhere
> - Add additional context in the commit messages for patches #3 and #4
> - In patch #2, don't remove indirect includes. Only remove includes
> which truly aren't used, suggested by Michael Kelley
>
> ---
> Nuno Das Neves (4):
> hyperv: Move hv_connection_id to hyperv-tlfs.h
> hyperv: Clean up unnecessary #includes
> hyperv: Add new Hyper-V headers in include/hyperv
> hyperv: Switch from hyperv-tlfs.h to hyperv/hvhdk.h
>
> arch/arm64/hyperv/hv_core.c | 3 +-
> arch/arm64/hyperv/mshyperv.c | 4 +-
> arch/arm64/include/asm/mshyperv.h | 2 +-
> arch/x86/hyperv/hv_apic.c | 1 -
> arch/x86/hyperv/hv_init.c | 21 +-
> arch/x86/hyperv/hv_proc.c | 3 +-
> arch/x86/hyperv/ivm.c | 1 -
> arch/x86/hyperv/mmu.c | 1 -
> arch/x86/hyperv/nested.c | 2 +-
> arch/x86/include/asm/kvm_host.h | 3 +-
> arch/x86/include/asm/mshyperv.h | 3 +-
> arch/x86/include/asm/svm.h | 2 +-
> arch/x86/kernel/cpu/mshyperv.c | 2 +-
> arch/x86/kvm/vmx/hyperv_evmcs.h | 2 +-
> arch/x86/kvm/vmx/vmx_onhyperv.h | 2 +-
> arch/x86/mm/pat/set_memory.c | 2 -
> drivers/clocksource/hyperv_timer.c | 2 +-
> drivers/hv/hv_balloon.c | 4 +-
> drivers/hv/hv_common.c | 2 +-
> drivers/hv/hv_kvp.c | 2 +-
> drivers/hv/hv_snapshot.c | 2 +-
> drivers/hv/hyperv_vmbus.h | 2 +-
> include/asm-generic/hyperv-tlfs.h | 9 +
> include/asm-generic/mshyperv.h | 2 +-
> include/clocksource/hyperv_timer.h | 2 +-
> include/hyperv/hvgdk.h | 303 +++++++
> include/hyperv/hvgdk_ext.h | 46 +
> include/hyperv/hvgdk_mini.h | 1295 ++++++++++++++++++++++++++++
> include/hyperv/hvhdk.h | 733 ++++++++++++++++
> include/hyperv/hvhdk_mini.h | 310 +++++++
> include/linux/hyperv.h | 11 +-
> net/vmw_vsock/hyperv_transport.c | 2 +-
> 32 files changed, 2729 insertions(+), 52 deletions(-)
> create mode 100644 include/hyperv/hvgdk.h
> create mode 100644 include/hyperv/hvgdk_ext.h
> create mode 100644 include/hyperv/hvgdk_mini.h
> create mode 100644 include/hyperv/hvhdk.h
> create mode 100644 include/hyperv/hvhdk_mini.h
>
> --
> 2.34.1