Re: [PATCH 1/2] powerpc64/bpf: Fix build break in bpf_jit_emit_func_call_rel()

[Madhavan Srinivasan]

On 7/29/26 10:15 PM, Christophe Leroy (CS GROUP) wrote:
> Le 29/07/2026 à 18:03, Saket Kumar Bhaskar a écrit :
> > From: Madhavan Srinivasan <maddy@xxxxxxxxxxxxx>
> >
> > With CONFIG_PPC_KERNEL_PCREL enabled, build breaks with below error:
> >
> >    CC      mm/dmapool.o
> >    CC      fs/readdir.o
> > arch/powerpc/net/bpf_jit_comp64.c: In function 
> > 'bpf_jit_emit_func_call_rel':
> > arch/powerpc/net/bpf_jit_comp64.c:475:13: error: unused variable 
> > 'ret' [-Werror=unused-variable]
> >    475 |         int ret;
> >        |             ^~~
> >
> > commit b55b6b9ad76c ("powerpc64/bpf: Add powerpc64 JIT support for 
> > timed may_goto")
> > introduced "ret" variable to bpf_jit_emit_func_call_rel() and it is 
> > used only in
> > else block of CONFIG_PPC_KERNEL_PCREL, fix by adding a "__maybe_unused"
>
> __maybe_unused doesn't fix the problem, it just hides it under the 
> carpet.
My bad, took the precedence from reladdr, may be it is better to change 
that too then

Maddy
> ret is used at only one place, move it's declaration their:
>
> #else
>     if (core_kernel_text(func_addr)) {
>         int ret = bpf_jit_emit_func_call(image, ctx, func_addr, _R12);
>         if (ret)
>             return ret;
>     } else {
>
> > Fixes: b55b6b9ad76c ("powerpc64/bpf: Add powerpc64 JIT support for 
> > timed may_goto")
> > Signed-off-by: Madhavan Srinivasan <maddy@xxxxxxxxxxxxx>
> > Signed-off-by: Saket Kumar Bhaskar <skb99@xxxxxxxxxxxxx>
> > ---
> >   arch/powerpc/net/bpf_jit_comp64.c | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/arch/powerpc/net/bpf_jit_comp64.c 
> > b/arch/powerpc/net/bpf_jit_comp64.c
> > index dab106cae22b..63952ef19256 100644
> > --- a/arch/powerpc/net/bpf_jit_comp64.c
> > +++ b/arch/powerpc/net/bpf_jit_comp64.c
> > @@ -472,7 +472,7 @@ int bpf_jit_emit_func_call_rel(u32 *image, u32 
> > *fimage, struct codegen_context *
> >   {
> >       unsigned long func_addr = func ? ppc_function_entry((void 
> > *)func) : 0;
> >       long __maybe_unused reladdr;
> > -    int ret;
> > +    int __maybe_unused ret;
> >         /* bpf to bpf call, func is not known in the initial pass. 
> > Emit 5 nops as a placeholder */
> >       if (!func) {