This is xnu-12377.1.9. See this file in:
#!special-case-list-v1
# rdar://139815990

[*]

# ARM64 specific blacklist
# __SECURITY_STACK_DISALLOWED_PUSH
fun:sleh_panic_lockdown_should_initiate_el1_sp0_sync

# [{coverage,thread}]

# src:*tests/unit/*.c
src:*tests/unit/mocks/*.h
src:*tests/unit/mocks/*.c
src:*tests/unit/mocks/fibers/*.c
src:*tests/unit/mocks/fibers/*.h
# for libmocks.dylib compilation
src:mocks/*.c
src:mocks/*.h
src:mocks/fibers/*.c
src:mocks/fibers/*.h

# disable ctx switches in printf-like functions
src:*bsd/kern/subr_prf.c
src:*osfmk/kern/printf.c
src:*osfmk/console/serial_general.c
src:*osfmk/console/serial_console.c

# blacklist str* function, but maybe we want to context switch in there?
src:*osfmk/device/subrs.c