linux.git/tools/testing/selftests/bpf/Makefile, branch v5.11

selftests/bpf: Clarify build error if no vmlinux

2020-12-16T18:04:34+00:00

If Makefile cannot find any of the vmlinux's in its VMLINUX_BTF_PATHS list,
it tries to run btftool incorrectly, with VMLINUX_BTF unset:

    bpftool btf dump file $(VMLINUX_BTF) format c

Such that the keyword 'format' is misinterpreted as the path to vmlinux.
The resulting build error message is fairly cryptic:

      GEN      vmlinux.h
    Error: failed to load BTF from format: No such file or directory

This patch makes the failure reason clearer by yielding this instead:

    Makefile:...: *** Cannot find a vmlinux for VMLINUX_BTF at any of
    "{paths}".  Stop.

Fixes: acbd06206bbb ("selftests/bpf: Add vmlinux.h selftest exercising tracing of syscalls")
Signed-off-by: Kamal Mostafa 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20201215182011.15755-1-kamal@canonical.com

selftests/bpf: Drop the need for LLVM's llc

2020-12-11T05:33:27+00:00

LLC is meant for compiler development and debugging. Consequently, it
exposes many low level options about its backend. To avoid future bugs
introduced by using the raw LLC tool, use clang directly so that all
appropriate options are passed to the back end.

Additionally, simplify the Makefile by removing the
CLANG_NATIVE_BPF_BUILD_RULE as it is not being use, stop passing
dwarfris attr since elfutils/libdw now supports the bpf backend (which
should work with any recent pahole), and stop passing alu32 since
-mcpu=v3 implies alu32.

Signed-off-by: Andrew Delgadillo 
Signed-off-by: Andrii Nakryiko 
Acked-by: Yonghong Song 
Link: https://lore.kernel.org/bpf/20201211004344.3355074-1-adelg@google.com

selftests/bpf: fix bpf_testmod.ko recompilation logic

2020-12-11T05:16:29+00:00

bpf_testmod.ko build rule declared dependency on VMLINUX_BTF, but the variable
itself was initialized after the rule was declared, which often caused
bpf_testmod.ko to not be re-compiled. Fix by moving VMLINUX_BTF determination
sooner.

Also enforce bpf_testmod.ko recompilation when we detect that vmlinux image
changed by removing bpf_testmod/bpf_testmod.ko. This is necessary to generate
correct module's split BTF. Without it, Kbuild's module build logic might
determine that nothing changed on the kernel side and thus bpf_testmod.ko
shouldn't be rebuilt, so won't re-generate module BTF, which often leads to
module's BTF with wrong string offsets against vmlinux BTF. Removing .ko file
forces Kbuild to re-build the module.

Reported-by: Alexei Starovoitov 
Fixes: 9f7fa225894c ("selftests/bpf: Add bpf_testmod kernel module for testing")
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/r/20201211015946.4062098-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov

selftests/bpf: Drop tcp-{client,server}.py from Makefile

2020-12-10T15:43:41+00:00

The files don't exist anymore so this breaks generic kselftest builds
when using "make install" or "make gen_tar".

Fixes: 247f0ec361b7 ("selftests/bpf: Drop python client/server in favor of threads")
Signed-off-by: Veronika Kabatova 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20201210120134.2148482-1-vkabatov@redhat.com

selftests/bpf: Xsk selftests - SKB POLL, NOPOLL

2020-12-09T15:44:45+00:00

Adds following tests:

1. AF_XDP SKB mode
   Generic mode XDP is driver independent, used when the driver does
   not have support for XDP. Works on any netdevice using sockets and
   generic XDP path. XDP hook from netif_receive_skb().
   a. nopoll - soft-irq processing
   b. poll - using poll() syscall

Signed-off-by: Weqaar Janjua 
Signed-off-by: Daniel Borkmann 
Tested-by: Yonghong Song 
Acked-by: Björn Töpel 
Link: https://lore.kernel.org/bpf/20201207215333.11586-3-weqaar.a.janjua@intel.com

selftests/bpf: Xsk selftests framework

2020-12-09T15:44:44+00:00

This patch adds AF_XDP selftests framework under selftests/bpf.

Topology:
---------
     -----------           -----------
     |  xskX   | --------- |  xskY   |
     -----------     |     -----------
          |          |          |
     -----------     |     ----------
     |  vethX  | --------- |  vethY |
     -----------   peer    ----------
          |          |          |
     namespaceX      |     namespaceY

Prerequisites setup by script test_xsk.sh:

   Set up veth interfaces as per the topology shown ^^:
   * setup two veth interfaces and one namespace
   ** veth in root namespace
   ** veth in af_xdp namespace
   ** namespace af_xdp
   * create a spec file veth.spec that includes this run-time configuration
   *** xxxx and yyyy are randomly generated 4 digit numbers used to avoid
       conflict with any existing interface
   * tests the veth and xsk layers of the topology

Signed-off-by: Weqaar Janjua 
Signed-off-by: Daniel Borkmann 
Tested-by: Yonghong Song 
Acked-by: Björn Töpel 
Link: https://lore.kernel.org/bpf/20201207215333.11586-2-weqaar.a.janjua@intel.com

selftests/bpf: Add bpf_testmod kernel module for testing

2020-12-04T01:38:20+00:00

Add bpf_testmod module, which is conceptually out-of-tree module and provides
ways for selftests/bpf to test various kernel module-related functionality:
raw tracepoint, fentry/fexit/fmod_ret, etc. This module will be auto-loaded by
test_progs test runner and expected by some of selftests to be present and
loaded.

Pahole currently isn't able to generate BTF for static functions in kernel
modules, so make sure traced function is global.

Signed-off-by: Andrii Nakryiko 
Signed-off-by: Alexei Starovoitov 
Acked-by: Martin KaFai Lau 
Link: https://lore.kernel.org/bpf/20201203204634.1325171-7-andrii@kernel.org

bpf: Fix cold build of test_progs-no_alu32

2020-12-03T20:10:53+00:00

This object lives inside the trunner output dir,
i.e. tools/testing/selftests/bpf/no_alu32/btf_data.o

At some point it gets copied into the parent directory during another
part of the build, but that doesn't happen when building
test_progs-no_alu32 from clean.

Signed-off-by: Brendan Jackman 
Signed-off-by: Andrii Nakryiko 
Acked-by: Jiri Olsa 
Link: https://lore.kernel.org/bpf/20201203120850.859170-1-jackmanb@google.com

selftests/bpf: Fix flavored variants of test_ima

2020-11-30T21:56:32+00:00

Flavored variants of test_progs (e.g. test_progs-no_alu32) change their
working directory to the corresponding subdirectory (e.g. no_alu32).
Since the setup script required by test_ima (ima_setup.sh) is not
mentioned in the dependencies, it does not get copied to these
subdirectories and causes flavored variants of test_ima to fail.

Adding the script to TRUNNER_EXTRA_FILES ensures that the file is also
copied to the subdirectories for the flavored variants of test_progs.

Fixes: 34b82d3ac105 ("bpf: Add a selftest for bpf_ima_inode_hash")
Reported-by: Yonghong Song 
Suggested-by: Yonghong Song 
Signed-off-by: KP Singh 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20201126184946.1708213-1-kpsingh@chromium.org

selftests/bpf: Fix broken riscv build

2020-11-19T01:44:59+00:00

The selftests/bpf Makefile includes system include directories from
the host, when building BPF programs. On RISC-V glibc requires that
__riscv_xlen is defined. This is not the case for "clang -target bpf",
which messes up __WORDSIZE (errno.h -> ... -> wordsize.h) and breaks
the build.

By explicitly defining __risc_xlen correctly for riscv, we can
workaround this.

Fixes: 167381f3eac0 ("selftests/bpf: Makefile fix "missing" headers on build with -idirafter")
Signed-off-by: Björn Töpel 
Signed-off-by: Andrii Nakryiko 
Acked-by: Luke Nelson 
Link: https://lore.kernel.org/bpf/20201118071640.83773-2-bjorn.topel@gmail.com