From: Björn Töpel <bjorn.to...@gmail.com> Hi!
This v2 series adds an RV64G BPF JIT to the kernel. At the moment the RISC-V Linux port does not support CONFIG_HAVE_KPROBES (Patrick Stählin sent out an RFC last year), which means that CONFIG_BPF_EVENTS is not supported. Thus, no tests involving BPF_PROG_TYPE_TRACEPOINT, BPF_PROG_TYPE_PERF_EVENT, BPF_PROG_TYPE_KPROBE and BPF_PROG_TYPE_RAW_TRACEPOINT passes. The implementation does not support "far branching" (>4KiB). Test results: # modprobe test_bpf test_bpf: Summary: 378 PASSED, 0 FAILED, [366/366 JIT'ed] # echo 1 > /proc/sys/kernel/unprivileged_bpf_disabled # ./test_verifier ... Summary: 761 PASSED, 507 SKIPPED, 2 FAILED Note that "test_verifier" was run with one build with CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS=y and one without, otherwise many of the the tests that require unaligned access were skipped. CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS=y: # echo 1 > /proc/sys/kernel/unprivileged_bpf_disabled # ./test_verifier | grep -c 'NOTE.*unknown align' 0 No CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS: # echo 1 > /proc/sys/kernel/unprivileged_bpf_disabled # ./test_verifier | grep -c 'NOTE.*unknown align' 59 The two failing test_verifier tests are: "ld_abs: vlan + abs, test 1" "ld_abs: jump around ld_abs" This is due to that "far branching" involved in those tests. All tests where done on QEMU emulator version 3.1.50 (v3.1.0-688-g8ae951fbc106). I'll test it on real hardware, when I get access to it. I'm routing this patch via bpf-next/netdev mailing list (after a conversation with Palmer at FOSDEM), mainly because the other JITs went that path. Again, thanks for all the comments! Cheers, Björn v1 -> v2: * Added JMP32 support. (Daniel) * Add RISC-V to Documentation/sysctl/net.txt. (Daniel) * Fixed seen_call() asymmetry. (Daniel) * Fixed broken bpf_flush_icache() range. (Daniel) * Added alignment annotations to some selftests. RFCv1 -> v1: * Cleaned up the Kconfig and net/Makefile. (Christoph) * Removed the entry-stub and squashed the build/config changes to be part of the JIT implementation. (Christoph) * Simplified the register tracking code. (Daniel) * Removed unused macros. (Daniel) * Added myself as maintainer and updated documentation. (Daniel) * Removed HAVE_EFFICIENT_UNALIGNED_ACCESS. (Christoph, Palmer) * Added tail-calls and cleaned up the code. Björn Töpel (4): bpf, riscv: add BPF JIT for RV64G MAINTAINERS: add RISC-V BPF JIT maintainer bpf, doc: add RISC-V JIT to BPF documentation selftests/bpf: add "any alignment" annotation for some tests Documentation/networking/filter.txt | 16 +- Documentation/sysctl/net.txt | 1 + MAINTAINERS | 6 + arch/riscv/Kconfig | 1 + arch/riscv/Makefile | 2 +- arch/riscv/net/Makefile | 1 + arch/riscv/net/bpf_jit_comp.c | 1602 +++++++++++++++++ .../selftests/bpf/verifier/ctx_sk_msg.c | 1 + .../testing/selftests/bpf/verifier/ctx_skb.c | 1 + tools/testing/selftests/bpf/verifier/jmp32.c | 22 + tools/testing/selftests/bpf/verifier/jset.c | 2 + .../selftests/bpf/verifier/spill_fill.c | 1 + .../selftests/bpf/verifier/spin_lock.c | 2 + .../selftests/bpf/verifier/value_ptr_arith.c | 4 + 14 files changed, 1654 insertions(+), 8 deletions(-) create mode 100644 arch/riscv/net/Makefile create mode 100644 arch/riscv/net/bpf_jit_comp.c -- 2.19.1
