Public bug reported:

My kernel running under UTM on an MacBook with M4 silicon is reporting
processor       : 0
BogoMIPS        : 48.00
Features        : fp asimd evtstrm aes pmull sha1 sha2 crc32 atomics fphp 
asimdhp cpuid asimdrdm jscvt fcma lrcpc dcpop sha3 asimddp sha512 asimdfhm dit 
uscat ilrcpc flagm sb paca pacg dcpodp sve2 flagm2 frint svei8mm svebf16 bf16 
afp smei16i64 smef64f64 smei8i32 smef16f32 smeb16f32 smef32f32 sme2 smei16i32 
smebi32i32
CPU implementer : 0x61
CPU architecture: 8
CPU variant     : 0x0
CPU part        : 0x000
CPU revision    : 0


The sve* features are incorrect as the the M4 does not implement SVE.

I believe this is a kernel bug that requires
https://web.git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=064737920bdbca86df91b96aed256e88018fef3a
backporting (backports were done to 6.6, 6.12 LTS releases, but not to
6.8).

There is a work-around, which is to disable SVE in grub, but really the
kernel should get this right.

GRUB_CMDLINE_LINUX_DEFAULT="arm64.nosve"

** Affects: linux (Ubuntu)
     Importance: Undecided
         Status: New

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https://bugs.launchpad.net/bugs/2104038

Title:
  Arm64 kernel incorrectly detects SVE hardware on VM with apple M4
  silicon

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