I'm trying to build a low memory footprint of RISC-V based seL4. I'm using QEMU/spike for now.

In seL4 12.0 I can modify spike.dts to 8.5 MB of memory 0x00880000.

42 memory@80000000 { 43 device_type = "memory"; 44 reg = <0x00000000 0x80000000 0x00000000 0x00880000>; 45 };

This is the smallest value that builds, lower than this I get the error:

[0/1] Re-running CMake... -- Found GCC with prefix riscv64-unknown-linux-gnu- STATUS,KernelDTSList: tools/dts/spike.dts -- /mnt/data/femur_12.0/build/kernel/gen_headers/plat/machine/devices_gen.h is out of date. Regenerating... STATUS,platform_yaml: /mnt/data/femur_12.0/build/kernel/gen_headers/plat/machine/platform_gen.yaml -- Detecting cached version of: musllibc -- Found valid cache entry for musllibc -- Configuring done -- Generating done -- Build files have been written to: /mnt/data/femur_12.0/build [18/36] Generating gen_headers/image_start_addr.h FAILED: elfloader-tool/gen_headers/image_start_addr.h cd /mnt/data/femur_12.0/build/elfloader-tool && sh -c "/mnt/data/femur_12.0/tools/elfloader-tool/../cmake-tool/helpers/shoehorn.py /mnt/data/femur_12.0/build/kernel/gen_headers/plat/machine/platform_gen.yaml /mnt/data/femur_12.0/build/elfloader-tool/archive.o > /mnt/data/femur_12.0/build/elfloader-tool/gen_headers//image_start_addr.h" shoehorn: fatal error: ELF-loader image "/mnt/data/femur_12.0/build/elfloader-tool/archive.o" of size 0x107548 does not fit within any memory region described in "{'devices': [{'end': 2147483648, 'start': 0}, {'end': 549755809792, 'start': 2155872256}], 'memory': [{'end': 2155872256, 'start': 2149580800}]}" ninja: build stopped: subcommand failed.

What do I need to modify to get to < 2 MB?

Thanks!