kern/60437: magic symlinks don't work in compat32

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>Number:         60437
>Category:       kern
>Synopsis:       magic symlinks don't work in compat32
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Jul 10 15:00:00 +0000 2026
>Originator:     Taylor R Campbell
>Release:        current, 11, 10, 9, ...
>Organization:
The Magic Symlink, starring Peter Sellers and Ringo Starr
>Environment:
>Description:

	Magic symlink patterns @machine_arch and @machine are done
	relative to the host kernel, not the userland execution
	environment, so /usr/tests/kernel/t_magic_symlinks cases
	`machine' and `machine_arch' fail.

>How-To-Repeat:

	1. enter an i386 chroot on an amd64 system (or similar compat
	   environment)

	2. cd /usr/tests/kernel && atf-run t_magic_symlinks

	Alternatively:

# sysctl -w vfs.generic.magiclinks=1
vfs.generic.magiclinks: 0 -> 1
# mkdir x86_64 i386 amd64
# touch x86_64/x86_64 i386/i386 amd64/amd64
# ln -s @machine_arch machine_arch
# ln -s @machine machine
# uname -p
i386
# uname -m
i386
# ls machine_arch
x86_64
# ls machine
amd64

>Fix:

	Seems like the symlink resolution should match uname -p and
	uname -m.