> -----Original Message----- > From: Stephen Hemminger <[email protected]> > Sent: Wednesday 24 June 2026 18:55 > To: [email protected] > Cc: Stephen Hemminger <[email protected]>; Konstantin Ananyev > <[email protected]>; > Marat Khalili <[email protected]> > Subject: [PATCH v5 5/9] test/bpf: add test for large shift > > There were multiple bugs with immediate values in shift instructions. > The code was not masking as required by RFC. > > Add new tests that cover these instructions. > > Signed-off-by: Stephen Hemminger <[email protected]>
Acked-by: Marat Khalili <[email protected]> > --- > app/test/test_bpf.c | 59 +++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 59 insertions(+) > > diff --git a/app/test/test_bpf.c b/app/test/test_bpf.c > index 232e9e2a98..0e5894a532 100644 > --- a/app/test/test_bpf.c > +++ b/app/test/test_bpf.c > @@ -2005,6 +2005,51 @@ test_div1_check(uint64_t rc, const void *arg) > return cmp_res(__func__, 0, rc, dve.out, dvt->out, sizeof(dve.out)); > } > > +/* > + * Shift counts are masked to the operand width (RFC 9669: 0x3f for 64-bit, > + * 0x1f for 32-bit). Counts >= 128 also exercise the x86 imm_size() path that > + * used to desync the stream, and the arm64 UBFM/SBFM immediate encoding. > + */ > +static const struct ebpf_insn test_shift_big_imm_prog[] = { > + { > + .code = (EBPF_ALU64 | EBPF_MOV | BPF_K), > + .dst_reg = EBPF_REG_0, > + .imm = 1 > + }, > + { > + .code = (EBPF_ALU64 | BPF_LSH | BPF_K), > + .dst_reg = EBPF_REG_0, > + .imm = 191 > + }, > + { > + .code = (EBPF_ALU64 | EBPF_ARSH | BPF_K), > + .dst_reg = EBPF_REG_0, > + .imm = 200 > + }, > + { > + .code = (EBPF_ALU64 | BPF_RSH | BPF_K), > + .dst_reg = EBPF_REG_0, > + .imm = 130 > + }, > + { > + .code = (BPF_JMP | EBPF_EXIT) > + }, > +}; > + > +static void > +test_shift_big_imm_prepare(void *arg) > +{ > + memset(arg, 0, sizeof(struct dummy_offset)); > +} > + > +static int > +test_shift_big_imm_check(uint64_t rc, const void *arg) > +{ > + uint64_t expect = 0x3FE0000000000000ULL; > + > + return cmp_res(__func__, expect, rc, arg, arg, 0); > +} > + > /* call test-cases */ > static const struct ebpf_insn test_call1_prog[] = { > > @@ -3409,6 +3454,20 @@ static const struct bpf_test tests[] = { > .prepare = test_mul1_prepare, > .check_result = test_div1_check, > }, > + { > + .name = "test_shift_big_imm", > + .arg_sz = sizeof(struct dummy_offset), > + .prm = { > + .ins = test_shift_big_imm_prog, > + .nb_ins = RTE_DIM(test_shift_big_imm_prog), > + .prog_arg = { > + .type = RTE_BPF_ARG_PTR, > + .size = sizeof(struct dummy_offset), > + }, > + }, > + .prepare = test_shift_big_imm_prepare, > + .check_result = test_shift_big_imm_check, > + }, > { > .name = "test_call1", > .arg_sz = sizeof(struct dummy_offset), > -- > 2.53.0
