linux.git/tools/testing/selftests/bpf/Makefile, branch v6.12 Linux kernel source tree selftests/bpf: Fix cross-compiling urandom_read 2024-10-11T02:08:14+00:00 Tony Ambardar tony.ambardar@gmail.com 2024-10-09T04:07:20+00:00 fd526e121c4d6f71aed82d21a8b8277b03e60b43 Linking of urandom_read and liburandom_read.so prefers LLVM's 'ld.lld' but falls back to using 'ld' if unsupported. However, this fallback discards any existing makefile macro for LD and can break cross-compilation. Fix by changing the fallback to use the target linker $(LD), passed via '-fuse-ld=' using an absolute path rather than a linker "flavour". Fixes: 08c79c9cd67f ("selftests/bpf: Don't force lld on non-x86 architectures") Signed-off-by: Tony Ambardar <tony.ambardar@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20241009040720.635260-1-tony.ambardar@gmail.com 
Linking of urandom_read and liburandom_read.so prefers LLVM's 'ld.lld' but
falls back to using 'ld' if unsupported. However, this fallback discards
any existing makefile macro for LD and can break cross-compilation.

Fix by changing the fallback to use the target linker $(LD), passed via
'-fuse-ld=' using an absolute path rather than a linker "flavour".

Fixes: 08c79c9cd67f ("selftests/bpf: Don't force lld on non-x86 architectures")
Signed-off-by: Tony Ambardar <tony.ambardar@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241009040720.635260-1-tony.ambardar@gmail.com
selftests/bpf: Add test for kfunc module order 2024-10-10T17:44:03+00:00 Simon Sundberg simon.sundberg@kau.se 2024-10-10T13:27:09+00:00 f91b256644ea6f7628580029c5a223573f55d98c Add a test case for kfuncs from multiple external modules, checking that the correct kfuncs are called regardless of which order they're called in. Specifically, check that calling the kfuncs in an order different from the one the modules' BTF are loaded in works. Signed-off-by: Simon Sundberg <simon.sundberg@kau.se> Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/r/20241010-fix-kfunc-btf-caching-for-modules-v2-3-745af6c1af98@redhat.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> 
Add a test case for kfuncs from multiple external modules, checking
that the correct kfuncs are called regardless of which order they're
called in. Specifically, check that calling the kfuncs in an order
different from the one the modules' BTF are loaded in works.

Signed-off-by: Simon Sundberg <simon.sundberg@kau.se>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20241010-fix-kfunc-btf-caching-for-modules-v2-3-745af6c1af98@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
selftests/bpf: add build ID tests 2024-09-11T16:58:31+00:00 Andrii Nakryiko andrii@kernel.org 2024-08-29T17:42:32+00:00 3c217a182018e6c6d381b3fdc32626275eefbfb0 Add a new set of tests validating behavior of capturing stack traces with build ID. We extend uprobe_multi target binary with ability to trigger uprobe (so that we can capture stack traces from it), but also we allow to force build ID data to be either resident or non-resident in memory (see also a comment about quirks of MADV_PAGEOUT). That way we can validate that in non-sleepable context we won't get build ID (as expected), but with sleepable uprobes we will get that build ID regardless of it being physically present in memory. Also, we add a small add-on linker script which reorders .note.gnu.build-id section and puts it after (big) .text section, putting build ID data outside of the very first page of ELF file. This will test all the relaxations we did in build ID parsing logic in kernel thanks to freader abstraction. Reviewed-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240829174232.3133883-11-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> 
Add a new set of tests validating behavior of capturing stack traces
with build ID. We extend uprobe_multi target binary with ability to
trigger uprobe (so that we can capture stack traces from it), but also
we allow to force build ID data to be either resident or non-resident in
memory (see also a comment about quirks of MADV_PAGEOUT).

That way we can validate that in non-sleepable context we won't get
build ID (as expected), but with sleepable uprobes we will get that
build ID regardless of it being physically present in memory.

Also, we add a small add-on linker script which reorders
.note.gnu.build-id section and puts it after (big) .text section,
putting build ID data outside of the very first page of ELF file. This
will test all the relaxations we did in build ID parsing logic in kernel
thanks to freader abstraction.

Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240829174232.3133883-11-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
selftests/bpf: Prefer static linking for LLVM libraries 2024-09-05T20:13:39+00:00 Eduard Zingerman eddyz87@gmail.com 2024-09-05T08:13:54+00:00 67ab80a01886a178c69c91728c49f94ccb71f338 It is not always convenient to have LLVM libraries installed inside CI rootfs images, thus request static libraries from llvm-config. Suggested-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/r/20240905081401.1894789-4-pulehui@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> 
It is not always convenient to have LLVM libraries installed inside CI
rootfs images, thus request static libraries from llvm-config.

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20240905081401.1894789-4-pulehui@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
selftests/bpf: Adapt OUTPUT appending logic to lower versions of Make 2024-09-05T20:13:39+00:00 Pu Lehui pulehui@huawei.com 2024-09-05T08:13:52+00:00 dc3a8804d790cc7dda442e5504a0c67435b356f4 The $(let ...) function is only supported by GNU Make version 4.4 [0] and above, otherwise the following exception file or directory will be generated: tools/testing/selftests/bpfFEATURE-DUMP.selftests tools/testing/selftests/bpffeature/ Considering that the GNU Make version of most Linux distributions is lower than 4.4, let us adapt the corresponding logic to it. Link: https://lists.gnu.org/archive/html/info-gnu/2022-10/msg00008.html [0] Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Pu Lehui <pulehui@huawei.com> Link: https://lore.kernel.org/r/20240905081401.1894789-2-pulehui@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> 
The $(let ...) function is only supported by GNU Make version 4.4 [0]
and above, otherwise the following exception file or directory will be
generated:

	tools/testing/selftests/bpfFEATURE-DUMP.selftests
	tools/testing/selftests/bpffeature/

Considering that the GNU Make version of most Linux distributions is
lower than 4.4, let us adapt the corresponding logic to it.

Link: https://lists.gnu.org/archive/html/info-gnu/2022-10/msg00008.html [0]
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Link: https://lore.kernel.org/r/20240905081401.1894789-2-pulehui@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
selftests/bpf: Do not update vmlinux.h unnecessarily 2024-08-30T18:54:14+00:00 Ihor Solodrai ihor.solodrai@pm.me 2024-08-28T17:46:23+00:00 2ad6d23f465a4f851e3bcf6d74c315ce7b2c205b %.bpf.o objects depend on vmlinux.h, which makes them transitively dependent on unnecessary libbpf headers. However vmlinux.h doesn't actually change as often. When generating vmlinux.h, compare it to a previous version and update it only if there are changes. Example of build time improvement (after first clean build): $ touch ../../../lib/bpf/bpf.h $ time make -j8 Before: real 1m37.592s After: real 0m27.310s Notice that %.bpf.o gen step is skipped if vmlinux.h hasn't changed. Signed-off-by: Ihor Solodrai <ihor.solodrai@pm.me> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/CAEf4BzY1z5cC7BKye8=A8aTVxpsCzD=p1jdTfKC7i0XVuYoHUQ@mail.gmail.com Link: https://lore.kernel.org/bpf/20240828174608.377204-2-ihor.solodrai@pm.me 
%.bpf.o objects depend on vmlinux.h, which makes them transitively
dependent on unnecessary libbpf headers. However vmlinux.h doesn't
actually change as often.

When generating vmlinux.h, compare it to a previous version and update
it only if there are changes.

Example of build time improvement (after first clean build):
  $ touch ../../../lib/bpf/bpf.h
  $ time make -j8
Before: real  1m37.592s
After:  real  0m27.310s

Notice that %.bpf.o gen step is skipped if vmlinux.h hasn't changed.

Signed-off-by: Ihor Solodrai <ihor.solodrai@pm.me>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/CAEf4BzY1z5cC7BKye8=A8aTVxpsCzD=p1jdTfKC7i0XVuYoHUQ@mail.gmail.com
Link: https://lore.kernel.org/bpf/20240828174608.377204-2-ihor.solodrai@pm.me
selftests/bpf: Specify libbpf headers required for %.bpf.o progs 2024-08-30T18:54:14+00:00 Ihor Solodrai ihor.solodrai@pm.me 2024-08-28T17:46:14+00:00 38960ac8f916d1e60d4ceb4735a93740c4308d9c Test %.bpf.o objects actually depend only on some libbpf headers. Define a list of required headers and use it as TRUNNER_BPF_OBJS dependency. bpf_*.h list was determined by: $ grep -rh 'include <bpf/bpf_' progs | sort -u Signed-off-by: Ihor Solodrai <ihor.solodrai@pm.me> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: Link: https://lore.kernel.org/bpf/20240828174608.377204-1-ihor.solodrai@pm.me https://lore.kernel.org/bpf/CAEf4BzYQ-j2i_xjs94Nn=8+FVfkWt51mLZyiYKiz9oA4Z=pCeA@mail.gmail.com/ 
Test %.bpf.o objects actually depend only on some libbpf headers.
Define a list of required headers and use it as TRUNNER_BPF_OBJS
dependency.

bpf_*.h list was determined by:

    $ grep -rh 'include <bpf/bpf_' progs | sort -u

Signed-off-by: Ihor Solodrai <ihor.solodrai@pm.me>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link:
Link: https://lore.kernel.org/bpf/20240828174608.377204-1-ihor.solodrai@pm.me

https://lore.kernel.org/bpf/CAEf4BzYQ-j2i_xjs94Nn=8+FVfkWt51mLZyiYKiz9oA4Z=pCeA@mail.gmail.com/
selftests/bpf: use simply-expanded variables for libpcap flags 2024-08-23T21:33:30+00:00 Eduard Zingerman eddyz87@gmail.com 2024-08-23T19:44:09+00:00 5772c3458bb8d17d763e0f411e1bae1bf4eda88d Save pkg-config output for libpcap as simply-expanded variables. For an obscure reason 'shell' call in LDLIBS/CFLAGS recursively expanded variables makes *.test.o files compilation non-parallel when make is executed with -j option. While at it, reuse 'pkg-config --cflags' call to define -DTRAFFIC_MONITOR=1 option, it's exit status is the same as for 'pkg-config --exists'. Fixes: f52403b6bfea ("selftests/bpf: Add traffic monitor functions.") Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20240823194409.774815-1-eddyz87@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> 
Save pkg-config output for libpcap as simply-expanded variables.
For an obscure reason 'shell' call in LDLIBS/CFLAGS recursively
expanded variables makes *.test.o files compilation non-parallel
when make is executed with -j option.

While at it, reuse 'pkg-config --cflags' call to define
-DTRAFFIC_MONITOR=1 option, it's exit status is the same as for
'pkg-config --exists'.

Fixes: f52403b6bfea ("selftests/bpf: Add traffic monitor functions.")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240823194409.774815-1-eddyz87@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2024-08-22T16:48:44+00:00 Alexei Starovoitov ast@kernel.org 2024-08-22T16:27:59+00:00 50c374c6d1a43db9444cb74cc09552c817db2a9b Cross-merge bpf fixes after downstream PR including important fixes (from bpf-next point of view): commit 41c24102af7b ("selftests/bpf: Filter out _GNU_SOURCE when compiling test_cpp") commit fdad456cbcca ("bpf: Fix updating attached freplace prog in prog_array map") No conflicts. Adjacent changes in: include/linux/bpf_verifier.h kernel/bpf/verifier.c tools/testing/selftests/bpf/Makefile Link: https://lore.kernel.org/bpf/20240813234307.82773-1-alexei.starovoitov@gmail.com/ Signed-off-by: Alexei Starovoitov <ast@kernel.org> 
Cross-merge bpf fixes after downstream PR including
important fixes (from bpf-next point of view):
commit 41c24102af7b ("selftests/bpf: Filter out _GNU_SOURCE when compiling test_cpp")
commit fdad456cbcca ("bpf: Fix updating attached freplace prog in prog_array map")

No conflicts.

Adjacent changes in:
include/linux/bpf_verifier.h
kernel/bpf/verifier.c
tools/testing/selftests/bpf/Makefile

Link: https://lore.kernel.org/bpf/20240813234307.82773-1-alexei.starovoitov@gmail.com/
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
selftests/bpf: utility function to get program disassembly after jit 2024-08-21T18:03:01+00:00 Eduard Zingerman eddyz87@gmail.com 2024-08-20T10:23:53+00:00 b991fc52070042468f31b70fb8ccab96ba351f8a This commit adds a utility function to get disassembled text for jited representation of a BPF program designated by file descriptor. Function prototype looks as follows: int get_jited_program_text(int fd, char *text, size_t text_sz) Where 'fd' is a file descriptor for the program, 'text' and 'text_sz' refer to a destination buffer for disassembled text. Output format looks as follows: 18: 77 06 ja L0 1a: 50 pushq %rax 1b: 48 89 e0 movq %rsp, %rax 1e: eb 01 jmp L1 20: 50 L0: pushq %rax 21: 50 L1: pushq %rax ^ ^^^^^^^^ ^ ^^^^^^^^^^^^^^^^^^ | binary insn | textual insn | representation | representation | | instruction offset inferred local label name The code and makefile changes are inspired by jit_disasm.c from bpftool. Use llvm libraries to disassemble BPF program instead of libbfd to avoid issues with disassembly output stability pointed out in [1]. Selftests makefile uses Makefile.feature to detect if LLVM libraries are available. If that is not the case selftests build proceeds but the function returns -EOPNOTSUPP at runtime. [1] commit eb9d1acf634b ("bpftool: Add LLVM as default library for disassembling JIT-ed programs") Acked-by: Yonghong Song <yonghong.song@linux.dev> Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20240820102357.3372779-6-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> 
This commit adds a utility function to get disassembled text for jited
representation of a BPF program designated by file descriptor.
Function prototype looks as follows:

    int get_jited_program_text(int fd, char *text, size_t text_sz)

Where 'fd' is a file descriptor for the program, 'text' and 'text_sz'
refer to a destination buffer for disassembled text.
Output format looks as follows:

    18:	77 06                               	ja	L0
    1a:	50                                  	pushq	%rax
    1b:	48 89 e0                            	movq	%rsp, %rax
    1e:	eb 01                               	jmp	L1
    20:	50                                  L0:	pushq	%rax
    21:	50                                  L1:	pushq	%rax
     ^  ^^^^^^^^                             ^  ^^^^^^^^^^^^^^^^^^
     |  binary insn                          |  textual insn
     |  representation                       |  representation
     |                                       |
    instruction offset              inferred local label name

The code and makefile changes are inspired by jit_disasm.c from bpftool.
Use llvm libraries to disassemble BPF program instead of libbfd to avoid
issues with disassembly output stability pointed out in [1].

Selftests makefile uses Makefile.feature to detect if LLVM libraries
are available. If that is not the case selftests build proceeds but
the function returns -EOPNOTSUPP at runtime.

[1] commit eb9d1acf634b ("bpftool: Add LLVM as default library for disassembling JIT-ed programs")

Acked-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240820102357.3372779-6-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>