freertos + fds

Hi. I am trying to add FDS to my application where I used freertos and ble. I tried few things always ending with hardfault, one time it was from Freertos scheduler and the other times I cannot really tell.

- first I was trying to simply add fds_record_write() as fds was already initilized by peer_manager

- second I removed peer manager and initlized fds myself, I got the fds_init event but on fds_record_write() attempt it failed with harfault - altthough call to fds_record_write() itself returned success

- third I took raw (unmodified) ble_app_hrs_freertos and tried to add fds_record_write() on every battery_level_update. 

Until I tried third solution I was thinking that maybe something was witihin my app but looks like it is something (bug?) with fds/freertos. 

Can someone advise me what is proper way to use FDS with Freertos?

Thanks