Documentation mess

[bjne]

For several days I have spent trying to decipher the documentation to understand how to properly flash a LFS image
to the esp8266 using esptool. I understand there are multiple ways, one can place the LFS image in spiffs, one can
place it at a offset, and in a partition? This is badly documented.

in user_config.h the following (LFS related) is defined

LUA_FLASH_STORE 0x10000

Which I understand defines the default size of the LFS image if its not overridden in partition table.

NODEMCU_LFS0_PARTITION 3
NODEMCU_LFS1_PARTITION 4

I am not really able to find any documentation about what this actually does.

Running the code:

do
  local s,p={},node.getpartitiontable()
  for _,k in ipairs{'lfs_addr','lfs_size','spiffs_addr','spiffs_size'} do
    s[#s+1] ='%s = 0x%06x' % {k, p[k]}
  end
  print ('{ %s }' % table.concat(s,', '))
end

outputs the following:

{ lfs_addr = 0x07a000, lfs_size = 0x010000, spiffs_addr = 0x08a000, spiffs_size = 0x373000 }

Given this information, I try to create a lfs image:

first a compact relocatable (https://nodemcu.readthedocs.io/en/dev/compiling/) documentation is hard to understand also here:

./luac.cross -f -m 0x10000  local/fs/init.lua
Image size: 5132

Then I believe I should flash this to the 0x07a000 region:

tools/toolchains/esptool.py --port /dev/ttyUSB0 write_flash -fm dio 0x07a000 luac.out
esptool.py v2.6
Serial port /dev/ttyUSB0
Connecting....
Detecting chip type... ESP8266
Chip is ESP8266EX
Features: WiFi
MAC: e8:db:84:eb:a8:e4
Uploading stub...
Running stub...
Stub running...
Configuring flash size...
Auto-detected Flash size: 4MB
Compressed 2068 bytes to 2079...
Wrote 2068 bytes (2079 compressed) at 0x0007a000 in 0.2 seconds (effective 88.5 kbit/s)...
Hash of data verified.

Leaving...
Hard resetting via RTS pin...

After resetting, serial console outputs:

Flash sig not correct: 0x00088b1e vs 0xfafaa154

Ok, so lets try to create a absolute addressed lfs image (even tho docs say:
_Note that the new NodeMCU loader uses the -f compact relocatable form and does relocation based on the Partition Table, so this option is deprecated and will be removed in future releases.)

./luac.cross -f -a 0x07a000 -s -m 0x10000  local/fs/init.lua
./luac.cross: '-e' absolute address must be valid flash address
usage: ./luac.cross [options] [filenames].

At this point I am really lost. can someone please try to clarify?
How does partition0 and partition1 relate to the lfs_addr?
How should I compile the LFS image?
How should I flash it?