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Was: [PATCH RFC bpf-next 1/3] bpf: report probe fault to BPF stderr To: Leon Hwang Cc: Andrii Nakryiko , Kumar Kartikeya Dwivedi , Menglong Dong , Menglong Dong , Alexei Starovoitov , bpf , LKML , linux-trace-kernel , jiang.biao@linux.dev Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Thu, Oct 9, 2025 at 7:15=E2=80=AFAM Leon Hwang wro= te: > > > The verifier can rewrite 'bpf_reg_aux()' into the following instructions: > > dst_reg =3D BPF_REG_AUX; > BPF_REG_AUX =3D 0; /* clear BPF_REG_AUX */ > > As for the architecture-specific implementation, BPF_REG_AUX can be > mapped to an appropriate register per arch =E2=80=94 for example, r11 on = x86_64. it's taken. There are no free registers.