linux 618 compat PR17842 does not apply to 2.3.5

[mabod]

This is for endeavouros:

I wanted to build zfs-dkms 2.3.5 with kernel 6.18 support. But PR #17842
does not apply cleanly. Also checking out zfs git repository and swithing branch to git checkout origin/zfs-2.3.5-staging does not help.

How can I build zfs 2.3.5 with kernel 6.18 support?

==> patch 17842.patch
patching file module/os/linux/zfs/abd_os.c
Hunk #2 succeeded at 1114 (offset 4 lines).
patching file module/os/linux/zfs/zvol_os.c
Hunk #1 FAILED at 21.
Hunk #2 FAILED at 1500.
Hunk #3 succeeded at 1665 (offset 10 lines).
Hunk #4 succeeded at 1673 (offset 10 lines).
Hunk #5 succeeded at 1681 (offset 10 lines).
Hunk #6 succeeded at 1783 (offset 12 lines).
2 out of 6 hunks FAILED -- saving rejects to file module/os/linux/zfs/zvol_os.c.rej
patching file config/kernel-block-device-operations.m4
patching file module/os/linux/zfs/zvol_os.c
Hunk #1 FAILED at 1032.
Hunk #2 succeeded at 1090 (offset 33 lines).
1 out of 2 hunks FAILED -- saving rejects to file module/os/linux/zfs/zvol_os.c.rej
patching file config/kernel-writeback.m4
patching file config/kernel-writepage_t.m4
patching file config/kernel.m4
Hunk #1 succeeded at 120 (offset -1 lines).
Hunk #2 succeeded at 238 (offset -2 lines).
patching file module/os/linux/zfs/zpl_file.c
Hunk #1 FAILED at 23.
Hunk #2 succeeded at 444 (offset -34 lines).
Hunk #3 succeeded at 466 (offset -34 lines).
1 out of 3 hunks FAILED -- saving rejects to file module/os/linux/zfs/zpl_file.c.rej
patching file config/kernel-namespace.m4
patching file config/kernel-userns-capabilities.m4
patching file config/kernel.m4
Hunk #1 succeeded at 135 (offset -1 lines).
Hunk #2 succeeded at 255 (offset -2 lines).
patching file module/os/linux/spl/spl-zone.c
patching file module/icp/algs/sha2/sha2_generic.c
patching file config/kernel-drop-inode.m4
patching file config/kernel.m4
Hunk #1 succeeded at 136 (offset -1 lines).
Hunk #2 succeeded at 257 (offset -2 lines).
patching file include/os/linux/kernel/linux/vfs_compat.h
patching file module/os/linux/zfs/zpl_super.c
Hunk #1 FAILED at 23.
Hunk #2 succeeded at 32 with fuzz 2 (offset -1 lines).
Hunk #3 FAILED at 105.
2 out of 3 hunks FAILED -- saving rejects to file module/os/linux/zfs/zpl_super.c.rej
==> ERROR: A failure occurred in prepare().
    Aborting...

[hphilm]

It needs to be properly backported ...