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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 /include | |
| parent | 2326ff8d5c6628e581c87f37a8f6db1db7dc00ee (diff) | |
| parent | d52f5c639dd8605d2563b77b190e278f615a2b8a (diff) | |
| download | cachepc-linux-9faaffbe85edcbdc54096f7f87baa3bc4842a7e2.tar.gz cachepc-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 'include')
| -rw-r--r-- | include/uapi/linux/btf.h | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/include/uapi/linux/btf.h b/include/uapi/linux/btf.h index deb12f755f0f..b0d8fea1951d 100644 --- a/include/uapi/linux/btf.h +++ b/include/uapi/linux/btf.h @@ -43,7 +43,7 @@ struct btf_type { * "size" tells the size of the type it is describing. * * "type" is used by PTR, TYPEDEF, VOLATILE, CONST, RESTRICT, - * FUNC, FUNC_PROTO, VAR and DECL_TAG. + * FUNC, FUNC_PROTO, VAR, DECL_TAG and TYPE_TAG. * "type" is a type_id referring to another type. */ union { @@ -75,6 +75,7 @@ enum { BTF_KIND_DATASEC = 15, /* Section */ BTF_KIND_FLOAT = 16, /* Floating point */ BTF_KIND_DECL_TAG = 17, /* Decl Tag */ + BTF_KIND_TYPE_TAG = 18, /* Type Tag */ NR_BTF_KINDS, BTF_KIND_MAX = NR_BTF_KINDS - 1, |