Re: [PATCH v4 02/24] xen: consolidate cpuid library

[Jan Beulich <jbeulich@xxxxxxxx>]

On 21.11.2025 11:57, Penny Zheng wrote:
> There are some cpuid library functions only referenced in
> XEN_DOMCTL_get{,set}_cpu_policy-case, and shall be wrapped with
> CONFIG_MGMT_HYPERCALLS later, otherwise they will become unreachable when
> MGMT_HYPERCALLS=n, and hence violate Misra 2.1
> - x86_cpu_policy_clear_out_of_range_leaves
>   - zero_leaves
> - x86_cpuid_copy_to_buffer
>   - copy_leaf_to_buffer
> - x86_cpuid_copy_from_buffer
> We seperate these functions by moving other functions to a new file named
> cpuid-generic.c, and modify related Makefile-s to retain same behavior.
> 
> Signed-off-by: Penny Zheng <Penny.Zheng@xxxxxxx>
> ---
> v3 -> v4:
> - new commit
> ---
>  tools/fuzz/cpu-policy/Makefile               |   2 +-
>  tools/fuzz/x86_instruction_emulator/Makefile |  10 +-
>  tools/libs/guest/Makefile.common             |   2 +-
>  tools/tests/cpu-policy/Makefile              |   2 +-
>  tools/tests/x86_emulator/Makefile            |   2 +-
>  xen/lib/x86/Makefile                         |   1 +
>  xen/lib/x86/cpuid-generic.c                  | 273 +++++++++++++++++++
>  xen/lib/x86/cpuid.c                          | 260 ------------------
>  8 files changed, 283 insertions(+), 269 deletions(-)
>  create mode 100644 xen/lib/x86/cpuid-generic.c

Andrew - what's your take on such a split? Personally I'm not overly
happy to see related functions be scattered across two files. The
separation also feels pretty random, posing the risk that later some
of the code may need to move back.

Penny, I also don't think "consolidate" is what is happening here.
Perhaps "split" would be getting closer?

Jan