Yes the Le Potato booloader issue exists in LE9.0 & 9.0.1 images, the problem that causes a hard lock/segfault after performing several hundred MB of reads/writes to the SD.
As documented in the Coreelec forum, overwriting the bootloader with a patched version solves the issue. I've just had to do it again after upgrading to 9.0.1 using the LE addon.
For the record one needs to download the patched bootloader to your Potato's filesystem (or somewhere it can access), ssh in and write the image over the bootloader on the SD using dd and reboot as follows...
Code
dd if=/path/to/bootloader.img of=/dev/mmcblk0 conv=fsync bs=1 count=112
dd if=/path/to/bootloader.img of=/dev/mmcblk0 conv=fsync bs=512 skip=1 seek=1
reboot
A simple test to see if it's resolved is to use the LE config addon to create a backup (if your backups are normally over 500MB or so).