Re: git: cd61eb4f6681 - main - zfs: Wire sha512 offload to the build

From: Alan Somers <asomers_at_freebsd.org>
Date: Fri, 03 Jul 2026 18:08:47 UTC 
On Thu, Jul 2, 2026 at 12:02 PM Alexander Motin <mav@freebsd.org> wrote:
>
> The branch main has been updated by mav:
>
> URL: https://cgit.FreeBSD.org/src/commit/?id=cd61eb4f6681b13d98b6a7be252500ad30f05f74
>
> commit cd61eb4f6681b13d98b6a7be252500ad30f05f74
> Author:     Alexander Motin <mav@FreeBSD.org>
> AuthorDate: 2026-07-02 17:58:12 +0000
> Commit:     Alexander Motin <mav@FreeBSD.org>
> CommitDate: 2026-07-02 17:58:12 +0000
>
>     zfs: Wire sha512 offload to the build
>
>     FreeBSD main just got the CPUID_STDEXT4_SHA512 define.
>
>     OpenZFS PR #18732

This commit breaks boot for me.  The kernel can't open the zroot pool,
leading to the familiar mountroot> prompt.  And in a UFS-root VM, I
can't load the ZFS kernel module.  It fails with:

link_elf_obj: symbol zfs_sha512_transform_sha512ext undefined
linker_load_file: /boot/kernel/zfs.ko - unsupported file type

On both systems, the CPU is a Ryzen 9 5950X, which does not support AVX-512.

Could we please revert the change for now?