Pulling down ToT, I'm seeing the following warning when building with clang:
CC arch/x86/lib/insn.o arch/x86/lib/insn-eval.c:780:10: error: implicit conversion from 'int' to 'char' changes value from 132 to -124 [-Werror,-Wconstant-conversion] return INSN_CODE_SEG_PARAMS(4, 8); ~~~~~~ ^~~~~~~~~~~~~~~~~~~~~~~~~~ ./arch/x86/include/asm/insn-eval.h:16:57: note: expanded from macro 'INSN_CODE_SEG_PARAMS' #define INSN_CODE_SEG_PARAMS(oper_sz, addr_sz) (oper_sz | (addr_sz << 4)) ~~~~~~~~^~~~~~~~~~~~~~~~ seems to be coming from commit 4efea85fb56fa "x86/insn-eval: Add function to get default params of code segment". Should this be an unsigned char (as well as seg_defs in arch/x86/kernel/umip.c? That might be an issue for returning -EINVAL, maybe an in/out parameter would be better?