On 7/22/21 1:57 PM, Yu-cheng Yu wrote: > In a signal, a task's IBT status needs to be saved to the signal frame, and > later restored in sigreturn. For the purpose, previous versions of the > series add a new struct to the signal frame. However, a new signal frame > format (or re-using a reserved space) introduces complex compatibility > issues. > > In the discussion (see link below), Andy Lutomirski proposed using a > ucontext flag. The approach is clean and eliminates most compatibility > issues. > > However, a legacy IA32 signal frame does not have ucontext and cannot > support a uc flag. Thus, > > - Disable IBT for ia32. > - In ia32 sigreturn, verify ibt is disabled. Acked-by: Andy Lutomirski <luto@xxxxxxxxxx>
