curtin misidentify /dev/md126p3 as a multipath device, generates unbootable grub config

For multipath issue I discovered that the legacy detection of multipath for RAID1 device might be the culprit, as they both share the same content:

legacy_detect_multipath found blkid info: {'/dev/loop1': {'BLOCK_SIZE': '131072', 'TYPE': 'squashfs'}, '/dev/nvme0n1p3': {'UUID': '7fbb4ad1-c9ed-4575-bdfd-54ac9622acc2', 'BLOCK_SIZE': '4096', 'TYPE': 'ext4', 'PARTUUID': '0625db5b-7af0-4e7d-b8a1-40fb6ab69859'}, '/dev/nvme0n1p1': {'UUID': '50BA-7B2F', 'BLOCK_SIZE': '512', 'TYPE': 'vfat', 'PARTUUID': '7913070e-7623-4697-a6c8-2d32cc96c640'}, '/dev/nvme0n1p2': {'UUID': 'F1EA-BF0A', 'BLOCK_SIZE': '512', 'TYPE': 'vfat', 'PARTUUID': '0b376157-97ff-4ac7-b911-493f4b93977e'}, '/dev/loop8': {'BLOCK_SIZE': '131072', 'TYPE': 'squashfs'}, '/dev/loop15': {'BLOCK_SIZE': '131072', 'TYPE': 'squashfs'}, '/dev/loop6': {'BLOCK_SIZE': '131072', 'TYPE': 'squashfs'}, '/dev/loop13': {'BLOCK_SIZE': '131072', 'TYPE': 'squashfs'}, '/dev/loop4': {'BLOCK_SIZE': '131072', 'TYPE': 'squashfs'}, '/dev/loop11': {'BLOCK_SIZE': '131072', 'TYPE': 'squashfs'}, '/dev/loop2': {'BLOCK_SIZE': '131072', 'TYPE': 'squashfs'}, '/dev/loop0': {'BLOCK_SIZE': '131072', 'TYPE': 'squashfs'}, '/dev/loop9': {'BLOCK_SIZE': '131072', 'TYPE': 'squashfs'}, '/dev/md126p2': {'UUID': 'F1EA-BF0A', 'BLOCK_SIZE': '512', 'TYPE': 'vfat', 'PARTUUID': '0b376157-97ff-4ac7-b911-493f4b93977e'}, '/dev/md126p3': {'UUID': '7fbb4ad1-c9ed-4575-bdfd-54ac9622acc2', 'BLOCK_SIZE': '4096', 'TYPE': 'ext4', 'PARTUUID': '0625db5b-7af0-4e7d-b8a1-40fb6ab69859'}, '/dev/md126p1': {'UUID': '50BA-7B2F', 'BLOCK_SIZE': '512', 'TYPE': 'vfat', 'PARTUUID': '7913070e-7623-4697-a6c8-2d32cc96c640'}, '/dev/loop16': {'BLOCK_SIZE': '131072', 'TYPE': 'squashfs'}, '/dev/loop7': {'BLOCK_SIZE': '131072', 'TYPE': 'squashfs'}, '/dev/nvme1n1p2': {'UUID': 'F1EA-BF0A', 'BLOCK_SIZE': '512', 'TYPE': 'vfat', 'PARTUUID': '0b376157-97ff-4ac7-b911-493f4b93977e'}, '/dev/nvme1n1p3': {'UUID': '7fbb4ad1-c9ed-4575-bdfd-54ac9622acc2', 'BLOCK_SIZE': '4096', 'TYPE': 'ext4', 'PARTUUID': '0625db5b-7af0-4e7d-b8a1-40fb6ab69859'}, '/dev/nvme1n1p1': {'UUID': '50BA-7B2F', 'BLOCK_SIZE': '512', 'TYPE': 'vfat', 'PARTUUID': '7913070e-7623-4697-a6c8-2d32cc96c640'}, '/dev/loop14': {'BLOCK_SIZE': '131072', 'TYPE': 'squashfs'}, '/dev/loop5': {'BLOCK_SIZE': '131072', 'TYPE': 'squashfs'}, '/dev/loop12': {'BLOCK_SIZE': '131072', 'TYPE': 'squashfs'}, '/dev/loop3': {'BLOCK_SIZE': '131072', 'TYPE': 'squashfs'}, '/dev/loop10': {'BLOCK_SIZE': '131072', 'TYPE': 'squashfs'}}
Running command ['lsblk', '--noheadings', '--bytes', '--pairs', '--output=ALIGNMENT,DISC-ALN,DISC-GRAN,DISC-MAX,DISC-ZERO,FSTYPE,GROUP,KNAME,LABEL,LOG-SEC,MAJ:MIN,MIN-IO,MODE,MODEL,MOUNTPOINT,NAME,OPT-IO,OWNER,PHY-SEC,RM,RO,ROTA,RQ-SIZE,SIZE,STATE,TYPE,UUID'] with allowed return codes [0] (capture=True)
target_devs: ['/dev/md126p3']
/dev/md126p3: 7fbb4ad1-c9ed-4575-bdfd-54ac9622acc2
Multipath detection found: True

Running command ['lsblk', '--noheadings', '--bytes', '--pairs', '--output=ALIGNMENT,DISC-ALN,DISC-GRAN,DISC-MAX,DISC-ZERO,FSTYPE,GROUP,KNAME,LABEL,LOG-SEC,MAJ:MIN,MIN-IO,MODE,MODEL,MOUNTPOINT,NAME,OPT-IO,OWNER,PHY-SEC,RM,RO,ROTA,RQ-SIZE,SIZE,STATE,TYPE,UUID'] with allowed return codes [0] (capture=True)
target_de...

The fix is included in Subiquity 25.04 https://github.com/canonical/subiquity/releases/tag/25.04

Hey, what is the status of this one in Noble?

I can confirm the MP has been merged in current ubuntu-desktop-bootstrap 24.04/stable (rev 413), but not subiquity 24.04/stable (rev 6405)

Marking fix released for noble since Yao did functional testing suing the 24.04/stable ubuntu-desktop-bootstrap snap. Thanks!