Stack size required for bios interrupt call

Question

I am working on a small bootloader for learning purposes. Is there any specification/information available about the (free) stack size required for a bios interrupt call?

Answer 1

before entering the interrupt handler, all registers are pushed to the stack along with the far return address, sum your registers sizes up and add the space needed to store the return address to get the minimal stack size .

take note that you will need some more space if you are pushing more data into the stack while in the interrupt handler