On 05.12.2025 13:40, Andrew Cooper wrote: > On 05/12/2025 12:01 pm, Andrew Cooper wrote: >> On 24/11/2025 3:01 pm, Jan Beulich wrote: >>> --- a/xen/arch/x86/include/asm/bug.h >>> +++ b/xen/arch/x86/include/asm/bug.h >>> @@ -21,7 +21,7 @@ >>> >>> #ifndef __ASSEMBLY__ >>> >>> -#define BUG_INSTR "ud2" >>> +#define BUG_INSTR ".byte 0xd6" /* UDB */ >>> #define BUG_ASM_CONST "c" >>> >>> #else /* !__ASSEMBLY__ */ >>> @@ -37,7 +37,7 @@ >>> .error "Invalid BUGFRAME index" >>> .endif >>> >>> - .L\@ud: ud2a >>> + .L\@ud: .byte 0xd6 /* UDB */ > > P.S. Presumably binutils is going to learn a udb mnemonic at some > point? Can we include a version number in the comment?
I has already learned it, so it'll be available from 2.46 onwards. I've added a comment, but aiui we'd then need to also cover Clang's integrated assembler (if and when that gains support). In the meantime I've made both comments say "UDB, requiring gas 2.46". Jan
