Add a type cast for set8->pairs to fix below compile warning:
main.c: In function 'sets_patch':
main.c:699:50: warning: comparison of distinct pointer types lacks a cast
699 | BUILD_BUG_ON(set8->pairs != &set8->pairs[0].id);
| ^~
Fixes: 9707ac4fe2 ("tools/resolve_btfids: Refactor set sorting with types from btf_ids.h")
Signed-off-by: Liwei Song <liwei.song.lsong@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20240722083305.4009723-1-liwei.song.lsong@gmail.com
The usage help for "bpftool prog help" contains a ° instead of the _
symbol for cgroup/sendmsg_unix. Fix the typo.
Fixes: 8b3cba987e ("bpftool: Add support for cgroup unix socket address hooks")
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20240717134508.77488-1-donald.hunter@gmail.com
Old versions of libbpf don't handle varying sizes of bpf_map_skeleton
struct correctly. As such, BPF skeleton generated by newest bpftool
might not be compatible with older libbpf (though only when libbpf is
used as a shared library), even though it, by design, should.
Going forward libbpf will be fixed, plus we'll release bug fixed
versions of relevant old libbpfs, but meanwhile try to mitigate from
bpftool side by conservatively assuming older and smaller definition of
bpf_map_skeleton, if possible. Meaning, if there are no struct_ops maps.
If there are struct_ops, then presumably user would like to have
auto-attaching logic and struct_ops map link placeholders, so use the
full bpf_map_skeleton definition in that case.
Acked-by: Quentin Monnet <qmo@kernel.org>
Co-developed-by: Mykyta Yatsenko <yatsenko@meta.com>
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240708204540.4188946-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
As Quentin said [0], BPF map pinning will fail if the pinmaps path is not
under the bpffs, like:
libbpf: specified path /home/ubuntu/test/sock_ops_map is not on BPF FS
Error: failed to pin all maps
[0] https://github.com/libbpf/bpftool/issues/146
Fixes: 3767a94b32 ("bpftool: add pinmaps argument to the load/loadall")
Signed-off-by: Tao Chen <chen.dylane@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Quentin Monnet <qmo@kernel.org>
Reviewed-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20240702131150.15622-1-chen.dylane@gmail.com
New versions of bpftool now emit additional link placeholders for BPF
maps (struct_ops maps are the only maps right now that support
attachment), and set up BPF skeleton in such a way that libbpf will
auto-attach BPF maps automatically, assumming libbpf is recent enough
(v1.5+). Old libbpf will do nothing with those links and won't attempt
to auto-attach maps. This allows user code to handle both pre-v1.5 and
v1.5+ versions of libbpf at runtime, if necessary.
But if users don't have (or don't want to) control bpftool version that
generates skeleton, then they can't just assume that skeleton will have
link placeholders. To make this detection possible and easy, let's add
the following to generated skeleton header file:
#define BPF_SKEL_SUPPORTS_MAP_AUTO_ATTACH 1
This can be used during compilation time to guard code that accesses
skel->links.<map> slots.
Note, if auto-attachment is undesirable, libbpf allows to disable this
through bpf_map__set_autoattach(map, false). This is necessary only on
libbpf v1.5+, older libbpf doesn't support map auto-attach anyways.
Libbpf version can be detected at compilation time using
LIBBPF_MAJOR_VERSION and LIBBPF_MINOR_VERSION macros, or at runtime with
libbpf_major_version() and libbpf_minor_version() APIs.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20240618183832.2535876-1-andrii@kernel.org
Now that btf_parse_elf() handles .BTF.base section presence,
we need to ensure that resolve_btfids uses .BTF.base when present
rather than the vmlinux base BTF passed in via the -B option.
Detect .BTF.base section presence and unset the base BTF path
to ensure that BTF ELF parsing will do the right thing.
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20240613095014.357981-7-alan.maguire@oracle.com
This patch enables dumping kfunc prototypes from bpftool. This is useful
b/c with this patch, end users will no longer have to manually define
kfunc prototypes. For the kernel tree, this also means we can optionally
drop kfunc prototypes from:
tools/testing/selftests/bpf/bpf_kfuncs.h
tools/testing/selftests/bpf/bpf_experimental.h
Example usage:
$ make PAHOLE=/home/dxu/dev/pahole/build/pahole -j30 vmlinux
$ ./tools/bpf/bpftool/bpftool btf dump file ./vmlinux format c | rg "__ksym;" | head -3
extern void cgroup_rstat_updated(struct cgroup *cgrp, int cpu) __weak __ksym;
extern void cgroup_rstat_flush(struct cgroup *cgrp) __weak __ksym;
extern struct bpf_key *bpf_lookup_user_key(u32 serial, u64 flags) __weak __ksym;
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Link: https://lore.kernel.org/r/bf6c08f9263c4bd9d10a717de95199d766a13f61.1718207789.git.dxu@dxuuu.xyz
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
When CONFIG_NETKIT=y,
bpftool-cgroup shows error even if the cgroup's path is correct:
$ bpftool cgroup tree /sys/fs/cgroup
CgroupPath
ID AttachType AttachFlags Name
Error: can't query bpf programs attached to /sys/fs/cgroup: No such device or address
>From strace and kernel tracing, I found netkit returned ENXIO and this command failed.
I think this AttachType(BPF_NETKIT_PRIMARY) is not relevant to cgroup.
bpftool-cgroup should query just only cgroup-related attach types.
v2->v3:
- removed an unnecessary check
v1->v2:
- used an array of cgroup attach types
Signed-off-by: Kenta Tada <tadakentaso@gmail.com>
Reviewed-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/r/20240607111704.6716-1-tadakentaso@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:
====================
pull-request: bpf-next 2024-06-06
We've added 54 non-merge commits during the last 10 day(s) which contain
a total of 50 files changed, 1887 insertions(+), 527 deletions(-).
The main changes are:
1) Add a user space notification mechanism via epoll when a struct_ops
object is getting detached/unregistered, from Kui-Feng Lee.
2) Big batch of BPF selftest refactoring for sockmap and BPF congctl
tests, from Geliang Tang.
3) Add BTF field (type and string fields, right now) iterator support
to libbpf instead of using existing callback-based approaches,
from Andrii Nakryiko.
4) Extend BPF selftests for the latter with a new btf_field_iter
selftest, from Alan Maguire.
5) Add new kfuncs for a generic, open-coded bits iterator,
from Yafang Shao.
6) Fix BPF selftests' kallsyms_find() helper under kernels configured
with CONFIG_LTO_CLANG_THIN, from Yonghong Song.
7) Remove a bunch of unused structs in BPF selftests,
from David Alan Gilbert.
8) Convert test_sockmap section names into names understood by libbpf
so it can deduce program type and attach type, from Jakub Sitnicki.
9) Extend libbpf with the ability to configure log verbosity
via LIBBPF_LOG_LEVEL environment variable, from Mykyta Yatsenko.
10) Fix BPF selftests with regards to bpf_cookie and find_vma flakiness
in nested VMs, from Song Liu.
11) Extend riscv32/64 JITs to introduce shift/add helpers to generate Zba
optimization, from Xiao Wang.
12) Enable BPF programs to declare arrays and struct fields with kptr,
bpf_rb_root, and bpf_list_head, from Kui-Feng Lee.
* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (54 commits)
selftests/bpf: Drop useless arguments of do_test in bpf_tcp_ca
selftests/bpf: Use start_test in test_dctcp in bpf_tcp_ca
selftests/bpf: Use start_test in test_dctcp_fallback in bpf_tcp_ca
selftests/bpf: Add start_test helper in bpf_tcp_ca
selftests/bpf: Use connect_to_fd_opts in do_test in bpf_tcp_ca
libbpf: Auto-attach struct_ops BPF maps in BPF skeleton
selftests/bpf: Add btf_field_iter selftests
selftests/bpf: Fix send_signal test with nested CONFIG_PARAVIRT
libbpf: Remove callback-based type/string BTF field visitor helpers
bpftool: Use BTF field iterator in btfgen
libbpf: Make use of BTF field iterator in BTF handling code
libbpf: Make use of BTF field iterator in BPF linker code
libbpf: Add BTF field iterator
selftests/bpf: Ignore .llvm.<hash> suffix in kallsyms_find()
selftests/bpf: Fix bpf_cookie and find_vma in nested VM
selftests/bpf: Test global bpf_list_head arrays.
selftests/bpf: Test global bpf_rb_root arrays and fields in nested struct types.
selftests/bpf: Test kptr arrays and kptrs in nested struct fields.
bpf: limit the number of levels of a nested struct type.
bpf: look into the types of the fields of a struct type recursively.
...
====================
Link: https://lore.kernel.org/r/20240606223146.23020-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Similarly to `bpf_program`, support `bpf_map` automatic attachment in
`bpf_object__attach_skeleton`. Currently only struct_ops maps could be
attached.
On bpftool side, code-generate links in skeleton struct for struct_ops maps.
Similarly to `bpf_program_skeleton`, set links in `bpf_map_skeleton`.
On libbpf side, extend `bpf_map` with new `autoattach` field to support
enabling or disabling autoattach functionality, introducing
getter/setter for this field.
`bpf_object__(attach|detach)_skeleton` is extended with
attaching/detaching struct_ops maps logic.
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240605175135.117127-1-yatsenko@meta.com
Switch bpftool's code which is using libbpf-internal
btf_type_visit_type_ids() helper to new btf_field_iter functionality.
This makes bpftool code simpler, but also unblocks removing libbpf's
btf_type_visit_type_ids() helper completely.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Alan Maguire <alan.maguire@oracle.com>
Reviewed-by: Quentin Monnet <qmo@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20240605001629.4061937-5-andrii@kernel.org
Correct typo in bpftool profiler and change all instances of 'MATRICS' to
'METRICS' in the profiler.bpf.c file.
Signed-off-by: Swan Beaujard <beaujardswan@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20240602225812.81171-1-beaujardswan@gmail.com
Cross-merge networking fixes after downstream PR.
Conflicts:
drivers/net/ethernet/ti/icssg/icssg_classifier.c
abd5576b9c ("net: ti: icssg-prueth: Add support for ICSSG switch firmware")
56a5cf538c ("net: ti: icssg-prueth: Fix start counter for ft1 filter")
https://lore.kernel.org/all/20240531123822.3bb7eadf@canb.auug.org.au/
No other adjacent changes.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
To support epoll, a new instance of file_operations, bpf_link_fops_poll,
has been added for links that support epoll. The pid_iter.bpf.c checks
f_ops for links and other BPF objects. The check should fail for struct_ops
links without this patch.
Acked-by: Quentin Monnet <qmo@kernel.org>
Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
Link: https://lore.kernel.org/r/20240530065946.979330-9-thinker.li@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
err is a 32-bit integer, but elf_update returns an off_t, which is 64-bit
at least on 64-bit platforms. If symbols_patch is called on a binary between
2-4GB in size, the result will be negative when cast to a 32-bit integer,
which the code assumes means an error occurred. This can wrongly trigger
build failures when building very large kernel images.
Fixes: fbbb68de80 ("bpf: Add resolve_btfids tool to resolve BTF IDs in ELF object")
Signed-off-by: Friedrich Vock <friedrich.vock@gmx.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240514070931.199694-1-friedrich.vock@gmx.de
LLVM 17 started treating const structs as constants:
* https://github.com/llvm/llvm-project/commit/0b2d5b967d98
Combined with pointer laundering via ptr_to_u64, which takes a const ptr,
but in reality treats the underlying memory as mutable, this makes clang
always pass zero to btf__type_by_id, which breaks full name resolution.
Disassembly before (LLVM 16) and after (LLVM 17):
- 8b 75 cc mov -0x34(%rbp),%esi
- e8 47 8d 02 00 call 3f5b0 <btf__type_by_id>
+ 31 f6 xor %esi,%esi
+ e8 a9 8c 02 00 call 3f510 <btf__type_by_id>
It's a bigger project to fix this properly (and a question whether LLVM
itself should detect this), but for right now let's just fix bpftool.
For more information, see this thread in bpf mailing list:
* https://lore.kernel.org/bpf/CABWYdi0ymezpYsQsPv7qzpx2fWuTkoD1-wG1eT-9x-TSREFrQg@mail.gmail.com/T/
Fixes: b662000aff ("bpftool: Adding support for BTF program names")
Signed-off-by: Ivan Babrou <ivan@cloudflare.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/bpf/20240520225149.5517-1-ivan@cloudflare.com
With pre-generated vmlinux.h there is no dependency on neither vmlinux
nor bootstrap bpftool. Define dependencies separately for both modes.
This avoids needless rebuilds in some corner cases.
Suggested-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20240513112658.43691-1-asavkov@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Sort bpftool c dump output; aiming to simplify vmlinux.h diffing and
forcing more natural type definitions ordering.
Definitions are sorted first by their BTF kind ranks, then by their base
type name and by their own name.
Type ranks
Assign ranks to btf kinds (defined in function btf_type_rank) to set
next order:
1. Anonymous enums/enums64
2. Named enums/enums64
3. Trivial types typedefs (ints, then floats)
4. Structs/Unions
5. Function prototypes
6. Forward declarations
Type rank is set to maximum for unnamed reference types, structs and
unions to avoid emitting those types early. They will be emitted as
part of the type chain starting with named type.
Lexicographical ordering
Each type is assigned a sort_name and own_name.
sort_name is the resolved name of the final base type for reference
types (typedef, pointer, array etc). Sorting by sort_name allows to
group typedefs of the same base type. sort_name for non-reference type
is the same as own_name. own_name is a direct name of particular type,
is used as final sorting step.
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <qmo@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240514131221.20585-1-yatsenko@meta.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
When building either tools/bpf/bpftool, or tools/testing/selftests/hid,
(the same Makefile is used for these), clang generates many instances of
the following:
"clang: warning: -lLLVM-17: 'linker' input unused"
Quentin points out that the LLVM version is only required in $(LIBS),
not in $(CFLAGS), so the fix is to remove it from CFLAGS.
Suggested-by: Quentin Monnet <qmo@kernel.org>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20240505230054.13813-1-jhubbard@nvidia.com
This commit contains a series of clean-ups and fixes for bpftool's bash
completion file:
- Make sure all local variables are declared as such.
- Make sure variables are initialised before being read.
- Update ELF section ("maps" -> ".maps") for looking up map names in
object files.
- Fix call to _init_completion.
- Move definition for MAP_TYPE and PROG_TYPE higher up in the scope to
avoid defining them multiple times, reuse MAP_TYPE where relevant.
- Simplify completion for "duration" keyword in "bpftool prog profile".
- Fix completion for "bpftool struct_ops register" and "bpftool link
(pin|detach)" where we would repeatedly suggest file names instead of
suggesting just one name.
- Fix completion for "bpftool iter pin ... map MAP" to account for the
"map" keyword.
- Add missing "detach" suggestion for "bpftool link".
Signed-off-by: Quentin Monnet <qmo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240413011427.14402-3-qmo@kernel.org
When using references to BPF programs, bpftool supports passing programs
by name on the command line. The manual pages for "bpftool prog" and
"bpftool map" (for prog_array updates) mention it, but we have a few
additional subcommands that support referencing programs by name but do
not mention it in their documentation. Let's update the pages for
subcommands "btf", "cgroup", and "net".
Similarly, we can reference maps by name when passing them to "bpftool
prog load", so we update the page for "bpftool prog" as well.
Signed-off-by: Quentin Monnet <qmo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240413011427.14402-2-qmo@kernel.org
When pinning programs/objects under PATH (eg: during "bpftool prog
loadall") the bpffs is mounted on the parent dir of PATH in the
following situations:
- the given dir exists but it is not bpffs.
- the given dir doesn't exist and the parent dir is not bpffs.
Mounting on the parent dir can also have the unintentional side-
effect of hiding other files located under the parent dir.
If the given dir exists but is not bpffs, then the bpffs should
be mounted on the given dir and not its parent dir.
Similarly, if the given dir doesn't exist and its parent dir is not
bpffs, then the given dir should be created and the bpffs should be
mounted on this new dir.
Fixes: 2a36c26fe3 ("bpftool: Support bpffs mountpoint as pin path for prog loadall")
Signed-off-by: Sahil Siddiq <icegambit91@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/2da44d24-74ae-a564-1764-afccf395eeec@isovalent.com/T/#t
Link: https://lore.kernel.org/bpf/20240404192219.52373-1-icegambit91@gmail.com
Closes: https://github.com/libbpf/bpftool/issues/100
Changes since v1:
- Split "mount_bpffs_for_pin" into two functions.
This is done to improve maintainability and readability.
Changes since v2:
- mount_bpffs_for_pin: rename to "create_and_mount_bpffs_dir".
- mount_bpffs_given_file: rename to "mount_bpffs_given_file".
- create_and_mount_bpffs_dir:
- introduce "dir_exists" boolean.
- remove new dir if "mnt_fs" fails.
- improve error handling and error messages.
Changes since v3:
- Rectify function name.
- Improve error messages and formatting.
- mount_bpffs_for_file:
- Check if dir exists before block_mount check.
Changes since v4:
- Use strdup instead of strcpy.
- create_and_mount_bpffs_dir:
- Use S_IRWXU instead of 0700.
- Improve error handling and formatting.
When generated BPF skeleton header is included in C++ code base, some
compiler setups will emit warning about using language extensions due to
typeof() usage, resulting in something like:
error: extension used [-Werror,-Wlanguage-extension-token]
obj->struct_ops.empty_tcp_ca = (typeof(obj->struct_ops.empty_tcp_ca))
^
It looks like __typeof__() is a preferred way to do typeof() with better
C++ compatibility behavior, so switch to that. With __typeof__() we get
no such warning.
Fixes: c2a0257c1e ("bpftool: Cast pointers for shadow types explicitly.")
Fixes: 00389c58ff ("bpftool: Add support for subskeletons")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Kui-Feng Lee <thinker.li@gmail.com>
Acked-by: Quentin Monnet <qmo@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20240401170713.2081368-1-andrii@kernel.org
Improve the formatting of the attach flags for cgroup programs in the
relevant man page, and fix typos ("can be on of", "an userspace inet
socket") when introducing that list. Also fix a couple of other trivial
issues in docs.
[ Quentin: Fixed trival issues in bpftool-gen.rst and bpftool-iter.rst ]
Signed-off-by: Rameez Rehman <rameezrehman408@hotmail.com>
Signed-off-by: Quentin Monnet <qmo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240331200346.29118-4-qmo@kernel.org
As it turns out, the terms in definition lists in the rST file are
already rendered with bold-ish formatting when generating the man pages;
all double-star sequences we have in the commands for the command
description are unnecessary, and can be removed to make the
documentation easier to read.
The rST files were automatically processed with:
sed -i '/DESCRIPTION/,/OPTIONS/ { /^\*/ s/\*\*//g }' b*.rst
Signed-off-by: Rameez Rehman <rameezrehman408@hotmail.com>
Signed-off-by: Quentin Monnet <qmo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240331200346.29118-3-qmo@kernel.org
The rST manual pages for bpftool would use a mix of tabs and spaces for
indentation. While this is the norm in C code, this is rather unusual
for rST documents, and over time we've seen many contributors use a
wrong level of indentation for documentation update.
Let's fix bpftool's indentation in docs once and for all:
- Let's use spaces, that are more common in rST files.
- Remove one level of indentation for the synopsis, the command
description, and the "see also" section. As a result, all sections
start with the same indentation level in the generated man page.
- Rewrap the paragraphs after the changes.
There is no content change in this patch, only indentation and
rewrapping changes. The wrapping in the generated source files for the
manual pages is changed, but the pages displayed with "man" remain the
same, apart from the adjusted indentation level on relevant sections.
[ Quentin: rebased on bpf-next, removed indent level for command
description and options, updated synopsis, command summary, and "see
also" sections. ]
Signed-off-by: Rameez Rehman <rameezrehman408@hotmail.com>
Signed-off-by: Quentin Monnet <qmo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240331200346.29118-2-qmo@kernel.org
BPF verifier emits "unknown func" message when given BPF program type
does not support BPF helper. This message may be confusing for users, as
important context that helper is unknown only to current program type is
not provided.
This patch changes message to "program of this type cannot use helper "
and aligns dependent code in libbpf and tests. Any suggestions on
improving/changing this message are welcome.
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/r/20240325152210.377548-1-yatsenko@meta.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Bpftool's Makefile uses $(HOST_CFLAGS) to build the bootstrap version of
bpftool, in order to pick the flags for the host (where we run the
bootstrap version) and not for the target system (where we plan to run
the full bpftool binary). But we pass too much information through this
variable.
In particular, we set HOST_CFLAGS by copying most of the $(CFLAGS); but
we do this after the feature detection for bpftool, which means that
$(CFLAGS), hence $(HOST_CFLAGS), contain all macro definitions for using
the different optional features. For example, -DHAVE_LLVM_SUPPORT may be
passed to the $(HOST_CFLAGS), even though the LLVM disassembler is not
used in the bootstrap version, and the related library may even be
missing for the host architecture.
A similar thing happens with the $(LDFLAGS), that we use unchanged for
linking the bootstrap version even though they may contains flags to
link against additional libraries.
To address the $(HOST_CFLAGS) issue, we move the definition of
$(HOST_CFLAGS) earlier in the Makefile, before the $(CFLAGS) update
resulting from the feature probing - none of which being relevant to the
bootstrap version. To clean up the $(LDFLAGS) for the bootstrap version,
we introduce a dedicated $(HOST_LDFLAGS) variable that we base on
$(LDFLAGS), before the feature probing as well.
On my setup, the following macro and libraries are removed from the
compiler invocation to build bpftool after this patch:
-DUSE_LIBCAP
-DHAVE_LLVM_SUPPORT
-I/usr/lib/llvm-17/include
-D_GNU_SOURCE
-D__STDC_CONSTANT_MACROS
-D__STDC_FORMAT_MACROS
-D__STDC_LIMIT_MACROS
-lLLVM-17
-L/usr/lib/llvm-17/lib
Another advantage of cleaning up these flags is that displaying
available features with "bpftool version" becomes more accurate for the
bootstrap bpftool, and no longer reflects the features detected (and
available only) for the final binary.
Cc: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Quentin Monnet <qmo@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Message-ID: <20240320014103.45641-1-qmo@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Commit d510296d33 ("bpftool: Use syscall/loader program in "prog load"
and "gen skeleton" command.") added new files to the list of objects to
compile in order to build the bootstrap version of bpftool. As far as I
can tell, these objects are unnecessary and were added by mistake; maybe
a draft version intended to add support for loading loader programs from
the bootstrap version. Anyway, we can remove these object files from the
list to make the bootstrap bpftool binary a tad smaller and faster to
build.
Fixes: d510296d33 ("bpftool: Use syscall/loader program in "prog load" and "gen skeleton" command.")
Signed-off-by: Quentin Monnet <qmo@kernel.org>
Message-ID: <20240320013457.44808-1-qmo@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
When trying to load the pid_iter BPF program used to iterate over the
PIDs of the processes holding file descriptors to BPF links, we would
unconditionally silence libbpf in order to keep the output clean if the
kernel does not support iterators and loading fails.
Although this is the desirable behaviour in most cases, this may hide
bugs in the pid_iter program that prevent it from loading, and it makes
it hard to debug such load failures, even in "debug" mode. Instead, it
makes more sense to print libbpf's logs when we pass the -d|--debug flag
to bpftool, so that users get the logs to investigate failures without
having to edit bpftool's source code.
Signed-off-by: Quentin Monnet <qmo@kernel.org>
Message-ID: <20240320012241.42991-1-qmo@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The selftests use
to tell LLVM about special pointers. For LLVM there is nothing "arena"
about them. They are simply pointers in a different address space.
Hence LLVM diff https://github.com/llvm/llvm-project/pull/85161 renamed:
. macro __BPF_FEATURE_ARENA_CAST -> __BPF_FEATURE_ADDR_SPACE_CAST
. global variables in __attribute__((address_space(N))) are now
placed in section named ".addr_space.N" instead of ".arena.N".
Adjust libbpf, bpftool, and selftests to match LLVM.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20240315021834.62988-3-alexei.starovoitov@gmail.com
According to a report, skeletons fail to assign shadow pointers when being
compiled with C++ programs. Unlike C doing implicit casting for void
pointers, C++ requires an explicit casting.
To support C++, we do explicit casting for each shadow pointer.
Also add struct_ops_module.skel.h to test_cpp to validate C++
compilation as part of BPF selftests.
Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20240312013726.1780720-1-thinker.li@gmail.com
LLVM automatically places __arena variables into ".arena.1" ELF section.
In order to use such global variables bpf program must include definition
of arena map in ".maps" section, like:
struct {
__uint(type, BPF_MAP_TYPE_ARENA);
__uint(map_flags, BPF_F_MMAPABLE);
__uint(max_entries, 1000); /* number of pages */
__ulong(map_extra, 2ull << 44); /* start of mmap() region */
} arena SEC(".maps");
libbpf recognizes both uses of arena and creates single `struct bpf_map *`
instance in libbpf APIs.
".arena.1" ELF section data is used as initial data image, which is exposed
through skeleton and bpf_map__initial_value() to the user, if they need to tune
it before the load phase. During load phase, this initial image is copied over
into mmap()'ed region corresponding to arena, and discarded.
Few small checks here and there had to be added to make sure this
approach works with bpf_map__initial_value(), mostly due to hard-coded
assumption that map->mmaped is set up with mmap() syscall and should be
munmap()'ed. For arena, .arena.1 can be (much) smaller than maximum
arena size, so this smaller data size has to be tracked separately.
Given it is enforced that there is only one arena for entire bpf_object
instance, we just keep it in a separate field. This can be generalized
if necessary later.
All global variables from ".arena.1" section are accessible from user space
via skel->arena->name_of_var.
For bss/data/rodata the skeleton/libbpf perform the following sequence:
1. addr = mmap(MAP_ANONYMOUS)
2. user space optionally modifies global vars
3. map_fd = bpf_create_map()
4. bpf_update_map_elem(map_fd, addr) // to store values into the kernel
5. mmap(addr, MAP_FIXED, map_fd)
after step 5 user spaces see the values it wrote at step 2 at the same addresses
arena doesn't support update_map_elem. Hence skeleton/libbpf do:
1. addr = malloc(sizeof SEC ".arena.1")
2. user space optionally modifies global vars
3. map_fd = bpf_create_map(MAP_TYPE_ARENA)
4. real_addr = mmap(map->map_extra, MAP_SHARED | MAP_FIXED, map_fd)
5. memcpy(real_addr, addr) // this will fault-in and allocate pages
At the end look and feel of global data vs __arena global data is the same from
bpf prog pov.
Another complication is:
struct {
__uint(type, BPF_MAP_TYPE_ARENA);
} arena SEC(".maps");
int __arena foo;
int bar;
ptr1 = &foo; // relocation against ".arena.1" section
ptr2 = &arena; // relocation against ".maps" section
ptr3 = &bar; // relocation against ".bss" section
Fo the kernel ptr1 and ptr2 has point to the same arena's map_fd
while ptr3 points to a different global array's map_fd.
For the verifier:
ptr1->type == unknown_scalar
ptr2->type == const_ptr_to_map
ptr3->type == ptr_to_map_value
After verification, from JIT pov all 3 ptr-s are normal ld_imm64 insns.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20240308010812.89848-11-alexei.starovoitov@gmail.com
It's not restricted to working with "internal" maps, it cares about any
map that can be mmap'ed. Reflect that in more succinct and generic name.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20240307031228.42896-6-alexei.starovoitov@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
The example in bpftool-gen.8 explains how to use the pointer of the shadow
type to change the value of a field of a struct_ops map.
Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20240229064523.2091270-5-thinker.li@gmail.com
Declares and defines a pointer of the shadow type for each struct_ops map.
The code generator will create an anonymous struct type as the shadow type
for each struct_ops map. The shadow type is translated from the original
struct type of the map. The user of the skeleton use pointers of them to
access the values of struct_ops maps.
However, shadow types only supports certain types of fields, including
scalar types and function pointers. Any fields of unsupported types are
translated into an array of characters to occupy the space of the original
field. Function pointers are translated into pointers of the struct
bpf_program. Additionally, padding fields are generated to occupy the space
between two consecutive fields.
The pointers of shadow types of struct_osp maps are initialized when
*__open_opts() in skeletons are called. For a map called FOO, the user can
access it through the pointer at skel->struct_ops.FOO.
Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20240229064523.2091270-4-thinker.li@gmail.com
The .BTF_ids section is pre-filled with zeroed BTF ID entries during the
build and afterwards patched by resolve_btfids with correct values.
Since resolve_btfids always writes in host-native endianness, it relies
on libelf to do the translation when the target ELF is cross-compiled to
a different endianness (this was introduced in commit 61e8aeda93
("bpf: Fix libelf endian handling in resolv_btfids")).
Unfortunately, the translation will corrupt the flags fields of SET8
entries because these were written during vmlinux compilation and are in
the correct endianness already. This will lead to numerous selftests
failures such as:
$ sudo ./test_verifier 502 502
#502/p sleepable fentry accept FAIL
Failed to load prog 'Invalid argument'!
bpf_fentry_test1 is not sleepable
verification time 34 usec
stack depth 0
processed 0 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0
Summary: 0 PASSED, 0 SKIPPED, 1 FAILED
Since it's not possible to instruct libelf to translate just certain
values, let's manually bswap the flags (both global and entry flags) in
resolve_btfids when needed, so that libelf then translates everything
correctly.
Fixes: ef2c6f370a ("tools/resolve_btfids: Add support for 8-byte BTF sets")
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/7b6bff690919555574ce0f13d2a5996cacf7bf69.1707223196.git.vmalik@redhat.com
Instead of using magic offsets to access BTF ID set data, leverage types
from btf_ids.h (btf_id_set and btf_id_set8) which define the actual
layout of the data. Thanks to this change, set sorting should also
continue working if the layout changes.
This requires to sync the definition of 'struct btf_id_set8' from
include/linux/btf_ids.h to tools/include/linux/btf_ids.h. We don't sync
the rest of the file at the moment, b/c that would require to also sync
multiple dependent headers and we don't need any other defs from
btf_ids.h.
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Daniel Xu <dxu@dxuuu.xyz>
Link: https://lore.kernel.org/bpf/ff7f062ddf6a00815fda3087957c4ce667f50532.1707223196.git.vmalik@redhat.com
Displaying cookies for kprobe multi link, in plain mode:
# bpftool link
...
1397: kprobe_multi prog 47532
kretprobe.multi func_cnt 3
addr cookie func [module]
ffffffff82b370c0 3 bpf_fentry_test1
ffffffff82b39780 1 bpf_fentry_test2
ffffffff82b397a0 2 bpf_fentry_test3
And in json mode:
# bpftool link -j | jq
...
{
"id": 1397,
"type": "kprobe_multi",
"prog_id": 47532,
"retprobe": true,
"func_cnt": 3,
"missed": 0,
"funcs": [
{
"addr": 18446744071607382208,
"func": "bpf_fentry_test1",
"module": null,
"cookie": 3
},
{
"addr": 18446744071607392128,
"func": "bpf_fentry_test2",
"module": null,
"cookie": 1
},
{
"addr": 18446744071607392160,
"func": "bpf_fentry_test3",
"module": null,
"cookie": 2
}
]
}
Cookie is attached to specific address, and because we sort addresses
before printing, we need to sort cookies the same way, hence adding
the struct addr_cookie to keep and sort them together.
Also adding missing dd.sym_count check to show_kprobe_multi_json.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240119110505.400573-9-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The error path frees wrong array, it should be ref_ctr_offsets.
Acked-by: Yafang Shao <laoar.shao@gmail.com>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Fixes: a7795698f8 ("bpftool: Add support to display uprobe_multi links")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240119110505.400573-4-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
There exists the following warning when building bpftool:
CC prog.o
prog.c: In function ‘profile_open_perf_events’:
prog.c:2301:24: warning: ‘calloc’ sizes specified with ‘sizeof’ in the earlier argument and not in the later argument [-Wcalloc-transposed-args]
2301 | sizeof(int), obj->rodata->num_cpu * obj->rodata->num_metric);
| ^~~
prog.c:2301:24: note: earlier argument should specify number of elements, later size of each element
Tested with the latest upstream GCC which contains a new warning option
-Wcalloc-transposed-args. The first argument to calloc is documented to
be number of elements in array, while the second argument is size of each
element, just switch the first and second arguments of calloc() to silence
the build warning, compile tested only.
Fixes: 47c09d6a9f ("bpftool: Introduce "prog profile" command")
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20240116061920.31172-1-yangtiezhu@loongson.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
