Greetings I am using a 4.0 compatible seL4 snapshot derived from mainline several months ago as a base for seL4/MIPS port. Currently, I am debugging sel4tests. My goal — make everything working before moving to hardware. By «everything» I mean different configurations of the system (optimization flags, syscall attributes, fast/slow path, etc). For example, most stable build uses «CONFIG_LIB_SEL4_INLINE_INVOCATIONS», less stable build, which I am debugging now, uses «CONFIG_LIB_SEL4_PUBLIC_SYMBOLS». This configuration crashes at the start when I am trying to allocate memory for the first test: Starting test suite sel4test Starting test 0: TEST_TRIVIAL0001 TEST_TRIVIAL0001 b24e68 b0cc4c b0cc2c b0cc2c sel4test-tests 0 0 * Loading segment 00400000-->005748a4 * Loading segment 00575000-->00689d84 alloc->num_cspace_slots = 30 alloc->num_cspace_slots = 29 alloc->num_cspace_slots = 28 alloc->num_cspace_slots = 27 alloc->num_cspace_slots = 26 alloc->num_cspace_slots = 25 alloc->num_cspace_slots = 24 alloc->num_cspace_slots = 23 alloc->num_cspace_slots = 22 alloc->num_cspace_slots = 21 alloc->num_cspace_slots = 20 alloc->num_cspace_slots = 19 alloc->num_cspace_slots = 18 alloc->num_cspace_slots = 17 alloc->num_cspace_slots = 16 alloc->num_cspace_slots = 15 alloc->num_cspace_slots = 14 alloc->num_cspace_slots = 13 alloc->num_cspace_slots = 12 alloc->num_cspace_slots = 11 alloc->num_cspace_slots = 10 alloc->num_cspace_slots = 9 alloc->num_cspace_slots = 8 alloc->num_cspace_slots = 7 alloc->num_cspace_slots = 6 alloc->num_cspace_slots = 5 alloc->num_cspace_slots = 4 alloc->num_cspace_slots = 3 alloc->num_cspace_slots = 2 alloc->num_cspace_slots = 1 _allocman_cspace_alloc@allocman.c:254 Regular cspace alloc failed, and failed from watermark alloc->num_cspace_slots == 0_refill_watermark:374 slota = 0 alloc->num_cspace_slots = 1 _allocman_cspace_alloc@allocman.c:254 Regular cspace alloc failed, and failed from watermark alloc->num_cspace_slots == 0_refill_watermark:374 slota = 0 alloc->num_cspace_slots = 1 _allocman_cspace_alloc@allocman.c:254 Regular cspace alloc failed, and failed from watermark I see, that: 243: error = alloc->cspace.alloc(alloc, alloc->cspace.cspace, slot); returns the error, and then we allocating memory from the watermark. In other builds (for example, with CONFIG_LIB_SEL4_INLINE_INVOCATIONS attributes), I do not see this issue - there are no errors on return. So, I need to debug function to be sure that I am receiving in the kernel proper arguments and so one, but I do not understand how this part of the code works. Do you have any documentation, or slides or just simple diagrams how this allocator work? What functions are responsible for generating error return, where exactly allocation is performed and how to debug this. Thank you.