This patch series adds support for hardware offload of programs containing BPF-to-BPF function calls. First, a new callback is added to the kernel verifier, to collect information after the main part of the verification has been performed. Then support for BPF-to-BPF calls is incrementally added to the nfp driver, before offloading programs containing such calls is eventually allowed by lifting the restriction in the kernel verifier, in the last patch. Please refer to individual patches for details.
Many thanks to Jiong and Jakub for their precious help and contribution on the main patches for the JIT-compiler, and everything related to stack accesses. Quentin Monnet (12): bpf: add verifier callback to get stack usage info for offloaded progs nfp: bpf: rename nfp_prog->stack_depth as nfp_prog->stack_frame_depth nfp: bpf: copy eBPF subprograms information from kernel verifier nfp: bpf: ignore helper-related checks for BPF calls in nfp verifier nfp: bpf: account for BPF-to-BPF calls when preparing nfp JIT nfp: bpf: add main logics for BPF-to-BPF calls support in nfp driver nfp: bpf: account for additional stack usage when checking stack limit nfp: bpf: update fixup function for BPF-to-BPF calls support nfp: bpf: fix return address from register-saving subroutine to callee nfp: bpf: optimise save/restore for R6~R9 based on register usage nfp: bpf: support pointers to other stack frames for BPF-to-BPF calls bpf: allow offload of programs with BPF-to-BPF function calls drivers/net/ethernet/netronome/nfp/bpf/jit.c | 381 ++++++++++++++++++++-- drivers/net/ethernet/netronome/nfp/bpf/main.h | 52 ++- drivers/net/ethernet/netronome/nfp/bpf/offload.c | 11 +- drivers/net/ethernet/netronome/nfp/bpf/verifier.c | 141 +++++++- drivers/net/ethernet/netronome/nfp/nfp_asm.h | 9 + drivers/net/netdevsim/bpf.c | 8 +- include/linux/bpf.h | 1 + include/linux/bpf_verifier.h | 1 + kernel/bpf/offload.c | 18 + kernel/bpf/verifier.c | 13 +- 10 files changed, 589 insertions(+), 46 deletions(-) -- 2.7.4
