NILFS2 in GRUB with blocksize=1024

[Vladimir 'φ-coder/phcoder' Serbinenko]

Hello, with the attached script grub-fstest fails completely with
blocksize=1024 and partially with 2048. Do you have any idea why? I
tried to debug and my finding is that grub_nilfs2_read_checkpoint reads
garbage. pptr makes sense but it points inside a file instead of to the
metadata. If I load the other superblock I'm able to read empty disk
(what's there before script starts putting files). The function calls
follow as:
grub_nilfs2_mount
grub_nilfs2_load_sb
grub_nilfs2_read_last_checkpoint
grub_nilfs2_read_checkpoint
grub_nilfs2_bmap_lookup
grub_nilfs2_direct_lookup
grub_nilfs2_dat_translate
grub_nilfs2_bmap_lookup
grub_nilfs2_btree_lookup
grub_nilfs2_btree_node_lookup
grub_nilfs2_btree_node_lookup
grub_nilfs2_btree_node_lookup
<---here it's already wrong--->
grub_nilfs2_read_inode
grub_nilfs2_bmap_lookup
grub_nilfs2_direct_lookup
grub_nilfs2_dat_translate
grub_nilfs2_bmap_lookup
grub_nilfs2_btree_lookup
grub_nilfs2_btree_node_lookup
grub_nilfs2_btree_node_lookup
grub_nilfs2_btree_node_lookup

-- 
Regards
Vladimir 'φ-coder/phcoder' Serbinenko

fstest.sh
Description: application/shellscript

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