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Björn Töpel
2353ecc6f9
This commit adds a BPF JIT for RV64G. The JIT is a two-pass JIT, and has a dynamic prolog/epilogue (similar to the MIPS64 BPF JIT) instead of static ones (e.g. x86_64). At the moment the RISC-V Linux port does not support CONFIG_HAVE_KPROBES, 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 (QEMU emulator version 3.1.50 (v3.1.0-688-g8ae951fbc106)). Signed-off-by: Björn Töpel <bjorn.topel@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.