On Tue, Jan 23, 2024 at 02:43:15PM +0100, Jan Beulich wrote: > On 23.01.2024 14:37, Roger Pau Monné wrote: > > On Tue, Jan 23, 2024 at 10:22:10AM +0100, Jan Beulich wrote: > >> On 22.01.2024 19:17, Andrew Cooper wrote: > >>> It is bad form to have inter-function fallthrough. It only functions > >>> right > >>> now because alignment padding bytes are NOPs. > >> > >> But that's a requirement anyway in executable sections. > > > > Really? I was under the impression we wanted to replace the padding > > nops with rets maybe, or even poison the padding with int3 or ud2. > > Well, that would be a decision of ours. Which then imo can't be described as > "only functions right now because ..." The assembler can't[1] use other than > NOPs by default, as it can't know whether fall-through is intended.
So it's not a strict requirement of ELF that padding is done using nops, it's just the default decision of the assembler because it doesn't know better. Thanks, Roger.
