# Compilation error when using R17 legato and CONFIG\_EXT4\_FS=y

**URL:** <https://forum.legato.io/t/compilation-error-when-using-r17-legato-and-config-ext4-fs-y/6890>\
**Category:** Legato Linux distribution (Yocto project)\
**Created:** [February 4, 2025, 3:03pm UTC](https://forum.legato.io/t/compilation-error-when-using-r17-legato-and-config-ext4-fs-y/6890 "2025-02-04T15:03:19Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Joao.Costa7](https://avatars.discourse-cdn.com/v4/letter/j/a88e4f/32.png) [@Joao.Costa7](https://forum.legato.io/u/Joao.Costa7)\
**Post date:** [February 4, 2025, 3:03pm UTC](https://forum.legato.io/t/compilation-error-when-using-r17-legato-and-config-ext4-fs-y/6890/1 "2025-02-04T15:03:19Z")

</div>

Hello everyone,

I tried to build a BSP with the R17 legato and I noticed that when I have this config flag: CONFIG\_EXT4\_FS=y there are some compilation errors:

```auto
| /home/coj8brg/workspace/from_scratch/slimscaley_bsp/linux_distro/yocto_nonus/poky/build_production/tmp/work-shared/swi-mdm9x28-wp/kernel-source/fs/ext4/namei.c: In function 'ext4_resetent':
| /home/coj8brg/workspace/from_scratch/slimscaley_bsp/linux_distro/yocto_nonus/poky/build_production/tmp/work-shared/swi-mdm9x28-wp/kernel-source/fs/ext4/namei.c:3686:11: error: too few arguments to function 'ext4_find_entry'
| 3686 | old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de, NULL);
| | ^ ~~~~~~~~~~~~~~
| /home/coj8brg/workspace/from_scratch/slimscaley_bsp/linux_distro/yocto_nonus/poky/build_production/tmp/work-shared/swi-mdm9x28-wp/kernel-source/fs/ext4/namei.c:1662:28: note: declared here
| 1662 | static struct buffer_head *ext4_find_entry(struct inode *dir,
| | ^ ~~~~~~~~~~~~~~
| /home/coj8brg/workspace/from_scratch/slimscaley_bsp/linux_distro/yocto_nonus/poky/build_production/tmp/work-shared/swi-mdm9x28-wp/kernel-source/fs/ext4/namei.c: In function 'ext4_rename':
| /home/coj8brg/workspace/from_scratch/slimscaley_bsp/linux_distro/yocto_nonus/poky/build_production/tmp/work-shared/swi-mdm9x28-wp/kernel-source/fs/ext4/namei.c:3865:6: error: implicit declaration of function 'ext4_encrypted_inode'; did you mean 'ext4_write_inode'? [-Werror=implicit-function-declaration]
| 3865 | ext4_encrypted_inode(new.dir) &&
| | ^ ~~~~~~~~~~~~~~~~~~~
| | ext4_write_inode
| cc1: some warnings being treated as errors

```

Has anyone had this error? Or does anyone know how to fix it (besides patching this file)?

---

<div class="post-metadata">

**Author:** ![jyijyi](https://sea1.discourse-cdn.com/flex019/user_avatar/forum.legato.io/jyijyi/32/822_2.png) [@jyijyi](https://forum.legato.io/u/jyijyi)\
**Post date:** [February 4, 2025, 4:24pm UTC](https://forum.legato.io/t/compilation-error-when-using-r17-legato-and-config-ext4-fs-y/6890/2 "2025-02-04T16:24:29Z")

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I remember it works in R13.3:

> **[Ext4 support on WP76xx](https://forum.sierrawireless.com/t/ext4-support-on-wp76xx/22984/7)**
>
> I just tried to enable in menuconfig filesystem → The Extended 4 (ext4) filesystem After that recompile the yocto image, now I can see: root@swi-mdm9x28-wp:~# cat /proc/filesystems nodev sysfs nodev rootfs nodev ramfs nodev bdev nodev ...

did you try other version like R16.3?

[https://source.sierrawireless.com/resources/airprime/software/wp76xx/wp76xx-firmware-release-16,-d-,3-components/#sthash.UTFgtfqz.dpbs](https://source.sierrawireless.com/resources/airprime/software/wp76xx/wp76xx-firmware-release-16,-d-,3-components/#sthash.UTFgtfqz.dpbs)

Lastly, you might need to port the code from here:

> <https://github.com/torvalds/linux/blob/v4.14/fs/ext4/namei.c>