`ERROR: modpost: "kmemdup" [fs/bcachefs/bcachefs.ko] undefined!` [400b3ab05c64d]

[ojab]

Failure to build the kernel

$ make 
...
MODPOST Module.symvers
ERROR: modpost: "kmemdup" [fs/nfs/nfs.ko] undefined!
ERROR: modpost: "kmemdup" [fs/nfs/blocklayout/blocklayoutdriver.ko] undefined!
ERROR: modpost: "kmemdup" [fs/nfsd/nfsd.ko] undefined!
ERROR: modpost: "kmemdup" [fs/ntfs3/ntfs3.ko] undefined!
ERROR: modpost: "kmemdup" [fs/btrfs/btrfs.ko] undefined!
ERROR: modpost: "kmemdup" [fs/bcachefs/bcachefs.ko] undefined!
ERROR: modpost: "kmemdup" [drivers/acpi/acpi_configfs.ko] undefined!
ERROR: modpost: "kmemdup" [drivers/char/virtio_console.ko] undefined!
ERROR: modpost: "kmemdup" [drivers/iommu/virtio-iommu.ko] undefined!
ERROR: modpost: "kmemdup" [drivers/gpu/drm/display/drm_display_helper.ko] undefined!
WARNING: modpost: suppressed 52 unresolved symbol warnings because there were too many)
make[1]: *** [scripts/Makefile.modpost:136: Module.symvers] Error 1
make: *** [Makefile:1978: modpost] Error 2

First failing commit is 400b3ab05c646cc14a8953f72c7ae2218d92da87

[RAOF]

This can be fixed by https://paste.rs/o3N0N