On Mon, Mar 9, 2020 at 1:59 PM Dave Hansen <dave.hansen@xxxxxxxxx> wrote: > > On 3/9/20 1:54 PM, H.J. Lu wrote: > >> If a program with the magic ELF CET flags missing can’t make a > >> thread with IBT and/or SHSTK enabled, then I think we’ve made an > >> error and should fix it. > >> > > A non-CET program can start a CET program and vice versa. > > Could we be specific here, please? > > HJ are you saying that: > * CET program can execve() a non-CET program, and > * a non-CET program can execve() a CET program > > ? Yes. > That's obvious. > > But what are the rules for clone()? Should there be rules for > mismatches for CET enabling between threads if a process (not child > processes)? What did you mean? A threaded application is either CET enabled or not CET enabled. A new thread from clone makes no difference. -- H.J.