In previous discussion ([1]), it is agreed that we should introduce cpu version 4 (llvm flag -mcpu=v4) which contains some instructions which can simplify code, make code easier to understand, fix the existing problem, or simply for feature completeness. More specifically, the following new insns are proposed: . sign extended load . sign extended mov . bswap . signed div/mod . ja with 32-bit offset This patch set added kernel support for insns proposed in [1] except BPF_ST which already has full kernel support. Beside the above proposed insns, LLVM will generate BPF_ST insn as well under -mcpu=v4 ([2]). The patchset implements interpreter and jit support for these new insns. It has minimum verifier support in order to pass bpf selftests. More work will be required to cover verification and other aspects (e.g. blinding, etc.). I send the patch set earlier and want to get some early feedbacks before I dig into verifier details. Patch 3 (sign-extension mov insns) prompts me to think whether we should have unsign-extension mov insns as well (see Patch 3 commit message for details). The last patch contains some statistics of how many new insns are actually generated in selftests. Please see each individual patch for details. [1] https://lore.kernel.org/bpf/4bfe98be-5333-1c7e-2f6d-42486c8ec039@xxxxxxxx/ [2] https://reviews.llvm.org/D144829 Yonghong Song (13): bpf: Support new sign-extension load insns bpf: Add verifier support for sign-extension load insns bpf: Support new sign-extension mov insns bpf: Support new unconditional bswap instruction bpf: Support new signed div/mod instructions. bpf: Support new 32bit offset jmp instruction bpf: Add kernel/bpftool asm support for new instructions selftests/bpf: Add unit tests for new sign-extension load insns selftests/bpf: Add unit tests for new sign-extension mov insns selftests/bpf: Add unit tests for new bswap insns selftests/bpf: Add unit tests for new sdiv/smod insns selftests/bpf: Add unit tests for new gotol insn selftests/bpf: Add a cpuv4 test runner for cpu=v4 testing arch/x86/net/bpf_jit_comp.c | 130 ++- include/uapi/linux/bpf.h | 1 + kernel/bpf/core.c | 170 +++- kernel/bpf/disasm.c | 57 +- kernel/bpf/verifier.c | 100 ++- tools/include/uapi/linux/bpf.h | 1 + tools/testing/selftests/bpf/Makefile | 18 +- .../selftests/bpf/prog_tests/verifier.c | 10 + .../selftests/bpf/progs/verifier_bswap.c | 45 ++ .../selftests/bpf/progs/verifier_gotol.c | 30 + .../selftests/bpf/progs/verifier_lds.c | 46 ++ .../selftests/bpf/progs/verifier_movs.c | 67 ++ .../selftests/bpf/progs/verifier_sdiv.c | 763 ++++++++++++++++++ 13 files changed, 1357 insertions(+), 81 deletions(-) create mode 100644 tools/testing/selftests/bpf/progs/verifier_bswap.c create mode 100644 tools/testing/selftests/bpf/progs/verifier_gotol.c create mode 100644 tools/testing/selftests/bpf/progs/verifier_lds.c create mode 100644 tools/testing/selftests/bpf/progs/verifier_movs.c create mode 100644 tools/testing/selftests/bpf/progs/verifier_sdiv.c -- 2.34.1
