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authorJakub Kicinski <kuba@kernel.org>2022-06-18 05:35:17 +0300
committerJakub Kicinski <kuba@kernel.org>2022-06-18 05:35:19 +0300
commit9fb424c4c29df0d7f39b686d4037cbc7e06ed7b5 (patch)
tree0fe62515d647b35b3c6ac06590469fe33d37dc1c /Documentation
parent4875d94c69d5a4836c4225b51429d277c297aae8 (diff)
parentf5be22c64bd6ee6c1cb0b34f4ff748d43879cd4c (diff)
downloadlinux-9fb424c4c29df0d7f39b686d4037cbc7e06ed7b5.tar.xz
Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says: ==================== pull-request: bpf-next 2022-06-17 We've added 72 non-merge commits during the last 15 day(s) which contain a total of 92 files changed, 4582 insertions(+), 834 deletions(-). The main changes are: 1) Add 64 bit enum value support to BTF, from Yonghong Song. 2) Implement support for sleepable BPF uprobe programs, from Delyan Kratunov. 3) Add new BPF helpers to issue and check TCP SYN cookies without binding to a socket especially useful in synproxy scenarios, from Maxim Mikityanskiy. 4) Fix libbpf's internal USDT address translation logic for shared libraries as well as uprobe's symbol file offset calculation, from Andrii Nakryiko. 5) Extend libbpf to provide an API for textual representation of the various map/prog/attach/link types and use it in bpftool, from Daniel Müller. 6) Provide BTF line info for RV64 and RV32 JITs, and fix a put_user bug in the core seen in 32 bit when storing BPF function addresses, from Pu Lehui. 7) Fix libbpf's BTF pointer size guessing by adding a list of various aliases for 'long' types, from Douglas Raillard. 8) Fix bpftool to readd setting rlimit since probing for memcg-based accounting has been unreliable and caused a regression on COS, from Quentin Monnet. 9) Fix UAF in BPF cgroup's effective program computation triggered upon BPF link detachment, from Tadeusz Struk. 10) Fix bpftool build bootstrapping during cross compilation which was pointing to the wrong AR process, from Shahab Vahedi. 11) Fix logic bug in libbpf's is_pow_of_2 implementation, from Yuze Chi. 12) BPF hash map optimization to avoid grabbing spinlocks of all CPUs when there is no free element. Also add a benchmark as reproducer, from Feng Zhou. 13) Fix bpftool's codegen to bail out when there's no BTF, from Michael Mullin. 14) Various minor cleanup and improvements all over the place. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (72 commits) bpf: Fix bpf_skc_lookup comment wrt. return type bpf: Fix non-static bpf_func_proto struct definitions selftests/bpf: Don't force lld on non-x86 architectures selftests/bpf: Add selftests for raw syncookie helpers in TC mode bpf: Allow the new syncookie helpers to work with SKBs selftests/bpf: Add selftests for raw syncookie helpers bpf: Add helpers to issue and check SYN cookies in XDP bpf: Allow helpers to accept pointers with a fixed size bpf: Fix documentation of th_len in bpf_tcp_{gen,check}_syncookie selftests/bpf: add tests for sleepable (uk)probes libbpf: add support for sleepable uprobe programs bpf: allow sleepable uprobe programs to attach bpf: implement sleepable uprobes by chaining gps bpf: move bpf_prog to bpf.h libbpf: Fix internal USDT address translation logic for shared libraries samples/bpf: Check detach prog exist or not in xdp_fwd selftests/bpf: Avoid skipping certain subtests selftests/bpf: Fix test_varlen verification failure with latest llvm bpftool: Do not check return value from libbpf_set_strict_mode() Revert "bpftool: Use libbpf 1.0 API mode instead of RLIMIT_MEMLOCK" ... ==================== Link: https://lore.kernel.org/r/20220617220836.7373-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/bpf/btf.rst43
-rw-r--r--Documentation/bpf/instruction-set.rst2
2 files changed, 38 insertions, 7 deletions
diff --git a/Documentation/bpf/btf.rst b/Documentation/bpf/btf.rst
index 7940da9bc6c1..f49aeef62d0c 100644
--- a/Documentation/bpf/btf.rst
+++ b/Documentation/bpf/btf.rst
@@ -74,7 +74,7 @@ sequentially and type id is assigned to each recognized type starting from id
#define BTF_KIND_ARRAY 3 /* Array */
#define BTF_KIND_STRUCT 4 /* Struct */
#define BTF_KIND_UNION 5 /* Union */
- #define BTF_KIND_ENUM 6 /* Enumeration */
+ #define BTF_KIND_ENUM 6 /* Enumeration up to 32-bit values */
#define BTF_KIND_FWD 7 /* Forward */
#define BTF_KIND_TYPEDEF 8 /* Typedef */
#define BTF_KIND_VOLATILE 9 /* Volatile */
@@ -87,6 +87,7 @@ sequentially and type id is assigned to each recognized type starting from id
#define BTF_KIND_FLOAT 16 /* Floating point */
#define BTF_KIND_DECL_TAG 17 /* Decl Tag */
#define BTF_KIND_TYPE_TAG 18 /* Type Tag */
+ #define BTF_KIND_ENUM64 19 /* Enumeration up to 64-bit values */
Note that the type section encodes debug info, not just pure types.
``BTF_KIND_FUNC`` is not a type, and it represents a defined subprogram.
@@ -101,10 +102,10 @@ Each type contains the following common data::
* bits 24-28: kind (e.g. int, ptr, array...etc)
* bits 29-30: unused
* bit 31: kind_flag, currently used by
- * struct, union and fwd
+ * struct, union, fwd, enum and enum64.
*/
__u32 info;
- /* "size" is used by INT, ENUM, STRUCT and UNION.
+ /* "size" is used by INT, ENUM, STRUCT, UNION and ENUM64.
* "size" tells the size of the type it is describing.
*
* "type" is used by PTR, TYPEDEF, VOLATILE, CONST, RESTRICT,
@@ -281,10 +282,10 @@ modes exist:
``struct btf_type`` encoding requirement:
* ``name_off``: 0 or offset to a valid C identifier
- * ``info.kind_flag``: 0
+ * ``info.kind_flag``: 0 for unsigned, 1 for signed
* ``info.kind``: BTF_KIND_ENUM
* ``info.vlen``: number of enum values
- * ``size``: 4
+ * ``size``: 1/2/4/8
``btf_type`` is followed by ``info.vlen`` number of ``struct btf_enum``.::
@@ -297,6 +298,10 @@ The ``btf_enum`` encoding:
* ``name_off``: offset to a valid C identifier
* ``val``: any value
+If the original enum value is signed and the size is less than 4,
+that value will be sign extended into 4 bytes. If the size is 8,
+the value will be truncated into 4 bytes.
+
2.2.7 BTF_KIND_FWD
~~~~~~~~~~~~~~~~~~
@@ -493,7 +498,7 @@ the attribute is applied to a ``struct``/``union`` member or
a ``func`` argument, and ``btf_decl_tag.component_idx`` should be a
valid index (starting from 0) pointing to a member or an argument.
-2.2.17 BTF_KIND_TYPE_TAG
+2.2.18 BTF_KIND_TYPE_TAG
~~~~~~~~~~~~~~~~~~~~~~~~
``struct btf_type`` encoding requirement:
@@ -516,6 +521,32 @@ type_tag, then zero or more const/volatile/restrict/typedef
and finally the base type. The base type is one of
int, ptr, array, struct, union, enum, func_proto and float types.
+2.2.19 BTF_KIND_ENUM64
+~~~~~~~~~~~~~~~~~~~~~~
+
+``struct btf_type`` encoding requirement:
+ * ``name_off``: 0 or offset to a valid C identifier
+ * ``info.kind_flag``: 0 for unsigned, 1 for signed
+ * ``info.kind``: BTF_KIND_ENUM64
+ * ``info.vlen``: number of enum values
+ * ``size``: 1/2/4/8
+
+``btf_type`` is followed by ``info.vlen`` number of ``struct btf_enum64``.::
+
+ struct btf_enum64 {
+ __u32 name_off;
+ __u32 val_lo32;
+ __u32 val_hi32;
+ };
+
+The ``btf_enum64`` encoding:
+ * ``name_off``: offset to a valid C identifier
+ * ``val_lo32``: lower 32-bit value for a 64-bit value
+ * ``val_hi32``: high 32-bit value for a 64-bit value
+
+If the original enum value is signed and the size is less than 8,
+that value will be sign extended into 8 bytes.
+
3. BTF Kernel API
=================
diff --git a/Documentation/bpf/instruction-set.rst b/Documentation/bpf/instruction-set.rst
index 1de6a57c7e1e..9e27fbdb2206 100644
--- a/Documentation/bpf/instruction-set.rst
+++ b/Documentation/bpf/instruction-set.rst
@@ -127,7 +127,7 @@ BPF_XOR | BPF_K | BPF_ALU64 means::
Byte swap instructions
----------------------
-The byte swap instructions use an instruction class of ``BFP_ALU`` and a 4-bit
+The byte swap instructions use an instruction class of ``BPF_ALU`` and a 4-bit
code field of ``BPF_END``.
The byte swap instructions operate on the destination register