Bpftool sync 2026-07-02#271
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qmonnet merged 6 commits intoJul 2, 2026
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struct_ops frees the global btf_vmlinux object.
In batch mode, a later struct_ops command can reuse stale state.
Reset the BTF pointer and cached map info state.
Fixes: 65c93628599d ("bpftool: Add struct_ops support")
Signed-off-by: Yichong Chen <chenyichong@uniontech.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/bpf/9F9017160ABE125F+20260624025055.1574875-3-chenyichong@uniontech.com
Adding BPF_OBJ_GET_INFO_BY_FD support for tracing_multi links. We expose following tracing_multi link data: - attach_type of the program - number of ids - array of BTF ids - array of its related kernel addresses - array of cookies The change follows the kprobe_multi and uprobe_multi link-info convention of optional output arrays with an in/out count, On top of standard tracing link data we also expose addresses, because they are useful info for user (especially when the attachment was done via pattern). This data is hidden when kallsyms does not allow exposing kernel pointer values. Assisted-by: Codex:GPT-5 Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Leon Hwang <leon.hwang@linux.dev> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20260629212208.895962-2-jolsa@kernel.org
Adding bpftool support to show tracing_multi link details,
the new output looks like:
# bpftool link
...
61: tracing_multi prog 167
attach_type trace_fentry_multi btf_obj_id 1 count 3
btf_id addr cookie func [module]
92598 ffffffff825017c4 10 bpf_fentry_test1
92600 ffffffff82503814 30 bpf_fentry_test2
92601 ffffffff82503824 20 bpf_fentry_test3
pids test_progs(1540)
Assisted-by: Codex:GPT-5
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260629212208.895962-4-jolsa@kernel.org
Commit 9080b97689db ("bpftool: Pass host flags to bootstrap libbpf")
started building the bootstrap libbpf with HOST_CFLAGS, stripping the
warning options that are unsuitable for that build by filtering out
-W -Wall -Wextra -Wformat -Wformat-signedness.
HOST_CFLAGS inherits EXTRA_WARNINGS, which includes -Wformat-security
and -Wformat-y2k. The filter drops -Wall and -Wformat (the latter being
what actually enables -Wformat), but leaves those two -Wformat-* children
in LIBBPF_BOOTSTRAP_CFLAGS. Building the bootstrap libbpf with it then
warns:
cc1: warning: '-Wformat-y2k' ignored without '-Wformat'
cc1: warning: '-Wformat-security' ignored without '-Wformat'
The warning is easy to miss in an in-tree build: tools/lib/bpf/Makefile
re-adds -Wall via "override CFLAGS += -Wall", which re-enables -Wformat
for the libbpf objects, so only libbpf's feature-detection probe (which
uses the passed CFLAGS verbatim) leaks the two warnings. The standalone
libbpf Makefile (github.com/libbpf/libbpf, used by the bpftool mirror)
instead uses "CFLAGS ?= ... -Wall", which the passed-in CFLAGS overrides,
so -Wall is never re-added and every bootstrap object warns.
Use a -Wformat% wildcard in the filter-out so the orphaned children are
removed together with the parent.
Fixes: 9080b97689db ("bpftool: Pass host flags to bootstrap libbpf")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20260630205418.3483969-1-andrii@kernel.org
get_map_kv_btf() caches the vmlinux BTF object when a map uses
btf_vmlinux_value_type_id. map dump released that object when the
command completed, but left the global pointer stale.
The same cached object can also be returned to print_key_value(), which
freed it directly. That leaves btf_vmlinux dangling before the command
cleanup path runs.
Use free_map_kv_btf() for per-entry cleanup, and reset the cached
btf_vmlinux pointer when the map command releases the object. This keeps
batch mode from reusing a freed BTF object.
Fixes: 4e1ea33292ff ("bpftool: Support dumping a map with btf_vmlinux_value_type_id")
Signed-off-by: Yichong Chen <chenyichong@uniontech.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/bpf/9072F43B3F74DF91+20260624025055.1574875-2-chenyichong@uniontech.com
Syncing latest bpftool commits from kernel repository. Baseline bpf-next commit: 53435562a725962e4de0c29653223129ba11643a Checkpoint bpf-next commit: 0b58988cacfc91604c4b5be2c3295f8aac0ee3d0 Baseline bpf commit: 9b51a6155d14389876916726430da30eabb1d4ed Checkpoint bpf commit: 9b51a6155d14389876916726430da30eabb1d4ed Andrii Nakryiko (1): bpftool: Strip all -Wformat* flags from bootstrap libbpf build Jiri Olsa (2): bpf: Add tracing_multi link info support bpftool: Add tracing_multi link info output Yichong Chen (2): tools/bpf/bpftool: Reset vmlinux BTF after map commands tools/bpf/bpftool: Reset vmlinux BTF after struct_ops commands include/uapi/linux/bpf.h | 9 +++ src/Makefile | 2 +- src/link.c | 133 +++++++++++++++++++++++++++++++++++++++ src/map.c | 12 +++- src/struct_ops.c | 4 ++ 5 files changed, 156 insertions(+), 4 deletions(-) Signed-off-by: Quentin Monnet <qmo@kernel.org>
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Sync bpftool repo with kernel. This is an automatic update performed by calling the sync script from this repo:
Setting a manual bpf-next tip to sync the
-Wformat*flags fix from Andrii without waiting for the next libbpf update.