kern/57411: zpool import panic()s on non standard -d $DEVPATH

[c%bow.st@localhost]

>Number:         57411
>Category:       kern
>Synopsis:       zpool import panic()s on non standard -d $DEVPATH
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed May 17 13:10:00 +0000 2023
>Originator:     Mathew, Cherry G.
>Release:        10.0_BETA
>Organization:
>Environment:
>Description:
a dom0 kernel panics reliably if you:

zpool import -o cachefile=none -d /dev0

where /dev0 was created as follows:

mkdir /dev0
cp /dev/MAKEFILE* /dev0
cd /dev0
sh MAKEFILE all
zpool import -o cachefile=none -d /dev0

panic (hand copied) below:

uvm_fault(0xffffffff812d3400, 0xfffffffffffff000, 1) -> e
fatal page fault in supervisor mode
trap type 6 code 0 rip 0xffffffff809b691a cs 0xe030 rflags 0x10286 cr 0xffffff...f0 ilevel 0 rsp 0xffffd7013915e9a0
curlwp 0xffffd7000c136640 pid 987.737 lowest kstack 0xffffd7013915a2c0
kernel: page fault[ 113.2756678]  trap, code=[>4;m0
Stopped in pid 987.737 (zpool) at netbsd:mutex_oncpu+0x1e:  movq 0(%rbx),%rax
db{3}> bt
mutex_oncpu() at netbsd:mutex_oncpu+0x1e
mutex_vector_enter() at netbsd:mutex_vector_enter+0xb7
vndopen() at netbsdvndopen+0xee
cdev_open() at netbsd:cdev_open+0x12c
spec_open() at netbsd:spec_open+0x237
VOP_OPEN() at netbsd:VOP_OPEN+0x38
vn_open() at netbsd:vn_open+0x32e
do_open() at netbsd:do_open+0xc3
do_sys_openat() at netbsd:do_sys_openat+0x74
sys_openat() at netbsd:sys_openat+0x22
syscall() at netbsd:syscall+0x18c
--- syscall (number 468) ---
netbsd:syscall+0x18c:

>How-To-Repeat:
Install 10.0_BETA dom0 with zfs partitions available for import.

Then import as above.
>Fix: