The i386 and x86-64 system call tables are different. When a 64-bit ftrace
tracks a 32-bit app, it needs to:
- use the 32-bit system call table
- project the 32-bit register set onto the underlying 64-bit register set
Down stream Fedora bug:
It is similar for ppc32 app on ppc64.
This kind of bugs belongs to bi-arch ones. What about creating a new tracker
for them. So that we can know how it works in general?