Re: [PATCH] powerpc32/bpf: return false from bpf_jit_supports_fsession() on ppc32

[IBM]

Karl Mehltretter <kmehltretter@xxxxxxxxx> writes:

> bpf_jit_supports_fsession() returns bool. Commit 92258b5bf1ec
> ("powerpc32/bpf: Add fsession support") made it return -EOPNOTSUPP on
> ppc32 until fsession is validated there. The negative value converts to
> true, so the verifier does not reject fsession programs on ppc32. Such a
> program loads, and only attaching it fails because
> __arch_prepare_bpf_trampoline() returns -EOPNOTSUPP on ppc32.
>
> Return false instead. The load then fails with "JIT does not support
> fsession". Tested with a ppc32 kernel on QEMU g3beige.
>

Fair enough.

> Fixes: 92258b5bf1ec ("powerpc32/bpf: Add fsession support")
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Reported-by: Dan Carpenter <error27@xxxxxxxxx>
> Closes: https://lore.kernel.org/r/202608010958.cYfBCQAC-lkp@xxxxxxxxx/
> Assisted-by: LLM
> Signed-off-by: Karl Mehltretter <kmehltretter@xxxxxxxxx>
> ---
>  arch/powerpc/net/bpf_jit_comp.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Sorry, I guess, this must have falled through the cracks.
Should mostly get queued for next -rc release.

LGTM. Feel free to add:
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@xxxxxxxxx>