This set adds BPF_J{LT,LE,SLT,SLE} instructions to the BPF insn set, interpreter, JIT hardening code and all JITs are also updated to support the new instructions. Basic idea is to reduce register pressure by avoiding BPF_J{GT,GE,SGT,SGE} rewrites. Removing the workaround for the rewrites in LLVM, this can result in shorter BPF programs, less stack usage and less verification complexity. First patch provides some more details on rationale. The LLVM patch [1] will be integrated to LLVM upstream later in a backwards compatible manner.
Thanks a lot! [1] https://github.com/borkmann/llvm/tree/bpf-insns Daniel Borkmann (9): bpf: add BPF_J{LT,LE,SLT,SLE} instructions bpf, x86: implement jiting of BPF_J{LT,LE,SLT,SLE} bpf, arm64: implement jiting of BPF_J{LT,LE,SLT,SLE} bpf, sparc64: implement jiting of BPF_J{LT,LE,SLT,SLE} bpf, s390x: implement jiting of BPF_J{LT,LE,SLT,SLE} bpf, ppc64: implement jiting of BPF_J{LT,LE,SLT,SLE} bpf, nfp: implement jiting of BPF_J{LT,LE} bpf: enable BPF_J{LT,LE,SLT,SLE} opcodes in verifier bpf: add test cases for new BPF_J{LT,LE,SLT,SLE} instructions Documentation/networking/filter.txt | 4 + arch/arm64/net/bpf_jit.h | 4 + arch/arm64/net/bpf_jit_comp.c | 20 ++ arch/powerpc/net/bpf_jit.h | 1 + arch/powerpc/net/bpf_jit_comp64.c | 20 ++ arch/s390/net/bpf_jit_comp.c | 24 ++ arch/sparc/net/bpf_jit_comp_64.c | 34 +++ arch/x86/net/bpf_jit_comp.c | 26 ++ drivers/net/ethernet/netronome/nfp/bpf/jit.c | 24 ++ include/uapi/linux/bpf.h | 5 + kernel/bpf/core.c | 60 +++++ kernel/bpf/verifier.c | 62 ++++- lib/test_bpf.c | 364 +++++++++++++++++++++++++++ net/core/filter.c | 21 +- tools/include/uapi/linux/bpf.h | 5 + tools/testing/selftests/bpf/test_verifier.c | 313 +++++++++++++++++++++++ 16 files changed, 979 insertions(+), 8 deletions(-) -- 1.9.3