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| author | Alexei Starovoitov <ast@kernel.org> | 2021-11-11 17:41:12 -0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2021-11-11 17:41:12 -0800 |
| commit | 9faaffbe85edcbdc54096f7f87baa3bc4842a7e2 (patch) | |
| tree | 6a8410367d37d8b76451a9f35e2f0b9565f8c557 /tools/bpf | |
| parent | Merge branch 'Future-proof more tricky libbpf APIs' (diff) | |
| parent | docs/bpf: Update documentation for BTF_KIND_TYPE_TAG support (diff) | |
| download | linux-9faaffbe85edcbdc54096f7f87baa3bc4842a7e2.tar.gz linux-9faaffbe85edcbdc54096f7f87baa3bc4842a7e2.zip | |
Merge branch 'Support BTF_KIND_TYPE_TAG for btf_type_tag attributes'
Yonghong Song says:
====================
LLVM patches ([1] for clang, [2] and [3] for BPF backend)
added support for btf_type_tag attributes. This patch
added support for the kernel.
The main motivation for btf_type_tag is to bring kernel
annotations __user, __rcu etc. to btf. With such information
available in btf, bpf verifier can detect mis-usages
and reject the program. For example, for __user tagged pointer,
developers can then use proper helper like bpf_probe_read_kernel()
etc. to read the data.
BTF_KIND_TYPE_TAG may also useful for other tracing
facility where instead of to require user to specify
kernel/user address type, the kernel can detect it
by itself with btf.
Patch 1 added support in kernel, Patch 2 for libbpf and Patch 3
for bpftool. Patches 4-9 are for bpf selftests and Patch 10
updated docs/bpf/btf.rst file with new btf kind.
[1] https://reviews.llvm.org/D111199
[2] https://reviews.llvm.org/D113222
[3] https://reviews.llvm.org/D113496
Changelogs:
v2 -> v3:
- rebase to resolve merge conflicts.
v1 -> v2:
- add more dedup tests.
- remove build requirement for LLVM=1.
- remove testing macro __has_attribute in bpf programs
as it is always defined in recent clang compilers.
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'tools/bpf')
| -rw-r--r-- | tools/bpf/bpftool/btf.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c index 223ac7676027..c7e3b0b0029e 100644 --- a/tools/bpf/bpftool/btf.c +++ b/tools/bpf/bpftool/btf.c @@ -39,6 +39,7 @@ static const char * const btf_kind_str[NR_BTF_KINDS] = { [BTF_KIND_DATASEC] = "DATASEC", [BTF_KIND_FLOAT] = "FLOAT", [BTF_KIND_DECL_TAG] = "DECL_TAG", + [BTF_KIND_TYPE_TAG] = "TYPE_TAG", }; struct btf_attach_point { @@ -142,6 +143,7 @@ static int dump_btf_type(const struct btf *btf, __u32 id, case BTF_KIND_VOLATILE: case BTF_KIND_RESTRICT: case BTF_KIND_TYPEDEF: + case BTF_KIND_TYPE_TAG: if (json_output) jsonw_uint_field(w, "type_id", t->type); else |