On 8/9/2021 4:04 PM, Andy Lutomirski wrote:
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>
Thanks!
