Problem Env:

OS :

Red Hat Enterprise Linux release 10.1 Beta (Coughlan)

Package :

mdadm-4.4-1.el10

Reproduce steps:

for  i in {1..3};do fallocate -l 200MiB /opt/loop$i; sleep 1; losetup /dev/loop$i /opt/loop$i;sleep 1 ; done
mdadm -CR /dev/md0 -l 1 -n2 /dev/loop1 /dev/loop2
mdadm --wait /dev/md0
yes | mkfs.ext4 /dev/md0'
mkdir /mnt/md_test
mount /dev/md0 /mnt/md_test
mdadm /dev/md0 --add /dev/loop3
mdadm --wait /dev/md0
mdadm --grow /dev/md0 -l5 -n3

Expect result:

1.The take over action should be done without error.

Actuallly result:

1.The OS hanging there.

Last known good working version:

mdadm-4.3-5.el10.x86_64