This reverts most of commit 30e0fca6c1.
It broke the case of non-leader MT exec when ptraced.
I think the bug it was intended to fix was already addressed by commit
788e05a67c.
Signed-off-by: Roland McGrath <[email protected]>
Acked-by: Oleg Nesterov <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>