[PATCH 1/3] bpf: fix signed shift overflows in ARM JIT

[Marat Khalili]

> > > > That tests do trigger it.
> > > >
> > > > RTE>>bpf_autotest
> > > > ../../src/lib/bpf/bpf_jit_arm64.c:320:18: runtime error: left shift of 1 by 31 places cannot be
> > > represented in type 'int'
> > >
> > > This is when ASAN is enabled. Right?
> >
> > More likely UBSAN, but yes.
> >
> > > Is it really generating BAD
> > > opcode(i.e emiter generating bad OPcode) and test fails?
> >
> > If allowed to finish the test does not fail.
> 
> Does that mean, it is a false positive? Right?

It depends on who you ask. Certain compilers with certain compilation options
tend to delete execution branches that cause UB, and the test may not be
detailed enough to notice this.

> Anyway, There is no harm in the new patch, Change the patch to use
> SHIFT macros from EAL.

Ok, will do. It is probably too late for the current release anyway.