On Fri, Feb 02, 2024 at 02:39:24PM -0800, Andrii Nakryiko wrote: > On Fri, Feb 2, 2024 at 8:34 AM Anton Protopopov <aspsk@xxxxxxxxxxxxx> wrote: > > > > This series adds support for mapping between xlated and original > > instructions offsets, mapping between xlated and jitted instructions > > offsets (x86), support for two new BPF instruction JA[SRC=1] > > (goto[l]_or_nop) and JA[SRC=3] (nop_or_goto[l]), and a new syscall to > > configure the jitted values of such instructions. > > > > This a follow up to the previous attempt to add static keys support > > (see [1], [2]) which implements lower-level functionality than what > > was proposed before. > > > > The first patch . > > The second patch adds xlated -> original mapping. > > The third patch adds . > > > > The fourth patch adds support for new instructions. > > And the fifth patch adds support for new syscall. > > > > The following patches are included: > > Patch 1 is a formal bug fix > > Patch 2 adds the xlated -> original mapping > > Patch 3 adds the xlated -> jitted mapping > > Patch 4 adds tests for instructions mappings > > Patch 5 adds bpftool support for printing new instructions > > Patch 6 add support for an extended JA instruction > > Patch 7 add support for kernel/bpftool to display new instructions > > Patch 8 adds a new BPF_STATIC_BRANCH_UPDATE syscall > > Patch 9 adds tests for the new ja* instructions and the new syscall > > > > Altogether this provides enough functionality to dynamically patch > > programs and support simple static keys. > > > > rfc -> v1: > > - converted to v1 based on the feedback (there was none) > > - bpftool support was added to dump new instructions > > - self-tests were added > > - minor fixes & checkpatch warnings > > > > [1] https://lpc.events/event/17/contributions/1608/attachments/1278/2578/bpf-static-keys.pdf > > [2] https://lore.kernel.org/bpf/20231206141030.1478753-1-aspsk@xxxxxxxxxxxxx/ > > [3] https://github.com/llvm/llvm-project/pull/75110 > > > > Anton Protopopov (9): > > bpf: fix potential error return > > bpf: keep track of and expose xlated insn offsets > > bpf: expose how xlated insns map to jitted insns > > selftests/bpf: Add tests for instructions mappings > > bpftool: dump new fields of bpf prog info > > bpf: add support for an extended JA instruction > > bpf: Add kernel/bpftool asm support for new instructions > > bpf: add BPF_STATIC_BRANCH_UPDATE syscall > > selftests/bpf: Add tests for new ja* instructions > > > > arch/x86/net/bpf_jit_comp.c | 73 ++++- > > include/linux/bpf.h | 11 + > > include/linux/bpf_verifier.h | 1 - > > include/linux/filter.h | 1 + > > include/uapi/linux/bpf.h | 26 ++ > > kernel/bpf/core.c | 67 ++++- > > kernel/bpf/disasm.c | 33 ++- > > kernel/bpf/syscall.c | 115 ++++++++ > > kernel/bpf/verifier.c | 58 +++- > > tools/bpf/bpftool/prog.c | 14 + > > tools/bpf/bpftool/xlated_dumper.c | 18 ++ > > tools/bpf/bpftool/xlated_dumper.h | 2 + > > tools/include/uapi/linux/bpf.h | 26 ++ > > .../bpf/prog_tests/bpf_insns_mappings.c | 156 ++++++++++ > > .../bpf/prog_tests/bpf_static_branches.c | 269 ++++++++++++++++++ > > .../selftests/bpf/progs/bpf_insns_mappings.c | 155 ++++++++++ > > 16 files changed, 1002 insertions(+), 23 deletions(-) > > create mode 100644 tools/testing/selftests/bpf/prog_tests/bpf_insns_mappings.c > > create mode 100644 tools/testing/selftests/bpf/prog_tests/bpf_static_branches.c > > create mode 100644 tools/testing/selftests/bpf/progs/bpf_insns_mappings.c > > > > -- > > 2.34.1 > > > > This fails to build in CI ([0]). I'll take a look at the patches next > week, sorry for the delay. Thanks Andrii! > [0] https://github.com/kernel-patches/bpf/actions/runs/7762232524/job/21172303431?pr=6380#step:11:77 Thanks, I will push a fix for this and some more fixes in v2 (besides this doc build failure there's a missing mutex for poking text and one NULL deref).
