write_buf_store crash

[Jim]

      I use nrf52832 sdk15.2 to develop products, use WDT to prevent program crashes, WDT set time is 10S, nrf52832 will be paired and bound after connecting with IOS phone, when nrf52832 and IOS binding, keep opening The IOS mobile phone's Bluetooth switch will crash, the function of the problem is write_buf_store, the following picture is the data in Call Stack+Locals, please help me to see what might be caused? How should it be solved? Thank you!

       call stack.zip

[Jim]

         I am not quite sure about the operating mechanism of fds_gc(). I suddenly thought that nrf52832 will call the "NVIC_SystemReset()" function for reset processing in a certain state. If it is being processed at some point in fds, call "NVIC_SystemReset( )) After the reset, call the fds_gc function to collect garbage when there is no problem? Is it necessary to determine certain flags before resetting, delay reset?
        In addition, I understand that peer mananger will use fds, but I don't know when I need to store records. When do I need to delete records? Is there any reference to this information? Thank you!