Commit Graph

272 Commits

Author SHA1 Message Date
Dave Thaler
04efaebd72 bpf, docs: Address comments from IETF Area Directors
This patch does the following to address IETF feedback:

* Remove mention of "program type" and reference future
  docs (and mention platform-specific docs exist) for
  helper functions and BTF. Addresses Roman Danyliw's
  comments based on GENART review from Ines Robles [0].

* Add reference for endianness as requested by John
  Scudder [1].

* Added bit numbers to top of 32-bit wide format diagrams
  as requested by Paul Wouters [2].

* Added more text about why BPF doesn't stand for anything, based
  on text from ebpf.io [3], as requested by Eric Vyncke and
  Gunter Van de Velde [4].

* Replaced "htobe16" (and similar) and the direction-specific
  description with just "be16" (and similar) and a direction-agnostic
  description, to match the direction-agnostic description in
  the Byteswap Instructions section. Based on feedback from Eric
  Vyncke [5].

[0] https://mailarchive.ietf.org/arch/msg/bpf/DvDgDWOiwk05OyNlWlAmELZFPlM/

[1] https://mailarchive.ietf.org/arch/msg/bpf/eKNXpU4jCLjsbZDSw8LjI29M3tM/

[2] https://mailarchive.ietf.org/arch/msg/bpf/hGk8HkYxeZTpdu9qW_MvbGKj7WU/

[3] https://ebpf.io/what-is-ebpf/#what-do-ebpf-and-bpf-stand-for

[4] https://mailarchive.ietf.org/arch/msg/bpf/i93lzdN3ewnzzS_JMbinCIYxAIU/

[5] https://mailarchive.ietf.org/arch/msg/bpf/KBWXbMeDcSrq4vsKR_KkBbV6hI4/

Acked-by: David Vernet <void@manifault.com>
Signed-off-by: Dave Thaler <dthaler1968@googlemail.com>
Link: https://lore.kernel.org/r/20240623150453.10613-1-dthaler1968@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-06-23 09:10:26 -07:00
Mykyta Yatsenko
eb4e772627 libbpf: Configure log verbosity with env variable
Configure logging verbosity by setting LIBBPF_LOG_LEVEL environment
variable, which is applied only to default logger. Once user set their
custom logging callback, it is up to them to handle filtering.

Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240524131840.114289-1-yatsenko@meta.com
2024-05-28 16:25:06 -07:00
Dave Thaler
e245ef8a0b bpf, docs: Fix instruction.rst indentation
The table captions patch corrected indented most tables to work with
the table directive for adding a caption but missed two of them.

Signed-off-by: Dave Thaler <dthaler1968@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240526061815.22497-1-dthaler1968@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-05-26 09:58:42 -07:00
Dave Thaler
f980f13e4e bpf, docs: Clarify call local offset
In the Jump instructions section it explains that the offset is
"relative to the instruction following the jump instruction".
But the program-local section confusingly said "referenced by
offset from the call instruction, similar to JA".

This patch updates that sentence with consistent wording, saying
it's relative to the instruction following the call instruction.

Signed-off-by: Dave Thaler <dthaler1968@gmail.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240525153332.21355-1-dthaler1968@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-05-25 10:41:57 -07:00
Dave Thaler
6a6d8b6f00 bpf, docs: Add table captions
As suggested by Ines Robles in his IETF GENART review at
https://datatracker.ietf.org/doc/review-ietf-bpf-isa-02-genart-lc-robles-2024-05-16/

Signed-off-by: Dave Thaler <dthaler1968@gmail.com>
Link: https://lore.kernel.org/r/20240524164618.18894-1-dthaler1968@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-05-25 10:39:31 -07:00
Dave Thaler
4e1215d9a1 bpf, docs: clarify sign extension of 64-bit use of 32-bit imm
imm is defined as a 32-bit signed integer.

{MOV, K, ALU64} says it does "dst = src" (where src is 'imm') and it
does do dst = (s64)imm, which in that sense does sign extend imm. The MOVSX
instruction is explained as sign extending, so added the example of
{MOV, K, ALU64} to make this more clear.

{JLE, K, JMP} says it does "PC += offset if dst <= src" (where src is 'imm',
and the comparison is unsigned). This was apparently ambiguous to some
readers as to whether the comparison was "dst <= (u64)(u32)imm" or
"dst <= (u64)(s64)imm" so added an example to make this more clear.

v1 -> v2: Address comments from Yonghong

Signed-off-by: Dave Thaler <dthaler1968@googlemail.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20240520215255.10595-1-dthaler1968@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-05-25 10:39:03 -07:00
Dave Thaler
a985fdca5e bpf, docs: Use RFC 2119 language for ISA requirements
Per IETF convention and discussion at LSF/MM/BPF, use MUST etc.
keywords as requested by IETF Area Director review.  Also as
requested, indicate that documenting BTF is out of scope of this
document and will be covered by a separate IETF specification.

Added paragraph about the terminology that is required IETF boilerplate
and must be worded exactly as such.

Signed-off-by: Dave Thaler <dthaler1968@googlemail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20240517165855.4688-1-dthaler1968@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-05-25 10:38:35 -07:00
Dave Thaler
4652072e7b bpf, docs: Move sentence about returning R0 to abi.rst
As discussed at LSF/MM/BPF, the sentence about using R0 for returning
values from calls is part of the calling convention and belongs in
abi.rst.  Any further additions or clarifications to this text are left
for future patches on abi.rst.  The current patch is simply to unblock
progression of instruction-set.rst to a standard.

In contrast, the restriction of register numbers to the range 0-10
is untouched, left in the instruction-set.rst definition of the
src_reg and dst_reg fields.

Signed-off-by: Dave Thaler <dthaler1968@googlemail.com>
Link: https://lore.kernel.org/r/20240517153445.3914-1-dthaler1968@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-05-25 10:37:49 -07:00
Puranjay Mohan
7a8030057f bpf, docs: Fix the description of 'src' in ALU instructions
An ALU instruction's source operand can be the value in the source
register or the 32-bit immediate value encoded in the instruction. This
is controlled by the 's' bit of the 'opcode'.

The current description explicitly uses the phrase 'value of the source
register' when defining the meaning of 'src'.

Change the description to use 'source operand' in place of 'value of the
source register'.

Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Acked-by: Dave Thaler <dthaler1968@gmail.com>
Link: https://lore.kernel.org/r/20240514130303.113607-1-puranjay@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-05-15 09:34:54 -07:00
Dave Thaler
07801a24e2 bpf, docs: Clarify PC use in instruction-set.rst
This patch elaborates on the use of PC by expanding the PC acronym,
explaining the units, and the relative position to which the offset
applies.

Signed-off-by: Dave Thaler <dthaler1968@googlemail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20240426231126.5130-1-dthaler1968@gmail.com
2024-04-29 11:54:42 +02:00
Dave Thaler
e51b907d40 bpf, docs: Add introduction for use in the ISA Internet Draft
The proposed intro paragraph text is derived from the first paragraph
of the IETF BPF WG charter at https://datatracker.ietf.org/wg/bpf/about/

Signed-off-by: Dave Thaler <dthaler1968@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20240422190942.24658-1-dthaler1968@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-04-25 19:15:21 -07:00
Dave Thaler
735f5b8a7c bpf, docs: Fix formatting nit in instruction-set.rst
Other places that had pseudocode were prefixed with ::
so as to appear in a literal block, but one place was inconsistent.
This patch fixes that inconsistency.

Signed-off-by: Dave Thaler <dthaler1968@googlemail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20240419213826.7301-1-dthaler1968@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-04-21 10:09:12 -07:00
Dave Thaler
db50040d09 bpf, docs: Clarify helper ID and pointer terms in instruction-set.rst
Per IETF 119 meeting discussion and mailing list discussion at
https://mailarchive.ietf.org/arch/msg/bpf/2JwWQwFdOeMGv0VTbD0CKWwAOEA/
the following changes are made.

First, say call by "static ID" rather than call by "address"

Second, change "pointer" to "address"

Signed-off-by: Dave Thaler <dthaler1968@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20240419203617.6850-1-dthaler1968@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-04-21 10:08:56 -07:00
Dave Thaler
00d5d22a5b bpf, docs: Editorial nits in instruction-set.rst
This patch addresses a number of editorial nits including
spelling, punctuation, grammar, and wording consistency issues
in instruction-set.rst.

Signed-off-by: Dave Thaler <dthaler1968@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20240405155245.3618-1-dthaler1968@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-04-05 10:42:30 -07:00
Dave Thaler
0ef05e258b bpf, docs: Rename legacy conformance group to packet
There could be other legacy conformance groups in the future,
so use a more descriptive name.  The status of the conformance
group in the IANA registry is what designates it as legacy,
not the name of the group.

Signed-off-by: Dave Thaler <dthaler1968@gmail.com>
Link: https://lore.kernel.org/r/20240302012229.16452-1-dthaler1968@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2024-03-04 14:31:06 +01:00
Dave Thaler
4e73e1bc1a bpf, docs: Use IETF format for field definitions in instruction-set.rst
In preparation for publication as an IETF RFC, the WG chairs asked me
to convert the document to use IETF packet format for field layout, so
this patch attempts to make it consistent with other IETF documents.

Some fields that are not byte aligned were previously inconsistent
in how values were defined.  Some were defined as the value of the
byte containing the field (like 0x20 for a field holding the high
four bits of the byte), and others were defined as the value of the
field itself (like 0x2).  This PR makes them be consistent in using
just the values of the field itself, which is IETF convention.

As a result, some of the defines that used BPF_* would no longer
match the value in the spec, and so this patch also drops the BPF_*
prefix to avoid confusion with the defines that are the full-byte
equivalent values.  For consistency, BPF_* is then dropped from
other fields too.  BPF_<foo> is thus the Linux implementation-specific
define for <foo> as it appears in the BPF ISA specification.

The syntax BPF_ADD | BPF_X | BPF_ALU only worked for full-byte
values so the convention {ADD, X, ALU} is proposed for referring
to field values instead.

Also replace the redundant "LSB bits" with "least significant bits".

A preview of what the resulting Internet Draft would look like can
be seen at:
https://htmlpreview.github.io/?https://raw.githubusercontent.com/dthaler/ebp
f-docs-1/format/draft-ietf-bpf-isa.html

v1->v2: Fix sphinx issue as recommended by David Vernet

Signed-off-by: Dave Thaler <dthaler1968@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20240301222337.15931-1-dthaler1968@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-03-02 21:40:14 -08:00
Kees Cook
896880ff30 bpf: Replace bpf_lpm_trie_key 0-length array with flexible array
Replace deprecated 0-length array in struct bpf_lpm_trie_key with
flexible array. Found with GCC 13:

../kernel/bpf/lpm_trie.c:207:51: warning: array subscript i is outside array bounds of 'const __u8[0]' {aka 'const unsigned char[]'} [-Warray-bounds=]
  207 |                                        *(__be16 *)&key->data[i]);
      |                                                   ^~~~~~~~~~~~~
../include/uapi/linux/swab.h:102:54: note: in definition of macro '__swab16'
  102 | #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x))
      |                                                      ^
../include/linux/byteorder/generic.h:97:21: note: in expansion of macro '__be16_to_cpu'
   97 | #define be16_to_cpu __be16_to_cpu
      |                     ^~~~~~~~~~~~~
../kernel/bpf/lpm_trie.c:206:28: note: in expansion of macro 'be16_to_cpu'
  206 |                 u16 diff = be16_to_cpu(*(__be16 *)&node->data[i]
^
      |                            ^~~~~~~~~~~
In file included from ../include/linux/bpf.h:7:
../include/uapi/linux/bpf.h:82:17: note: while referencing 'data'
   82 |         __u8    data[0];        /* Arbitrary size */
      |                 ^~~~

And found at run-time under CONFIG_FORTIFY_SOURCE:

  UBSAN: array-index-out-of-bounds in kernel/bpf/lpm_trie.c:218:49
  index 0 is out of range for type '__u8 [*]'

Changing struct bpf_lpm_trie_key is difficult since has been used by
userspace. For example, in Cilium:

	struct egress_gw_policy_key {
	        struct bpf_lpm_trie_key lpm_key;
	        __u32 saddr;
	        __u32 daddr;
	};

While direct references to the "data" member haven't been found, there
are static initializers what include the final member. For example,
the "{}" here:

        struct egress_gw_policy_key in_key = {
                .lpm_key = { 32 + 24, {} },
                .saddr   = CLIENT_IP,
                .daddr   = EXTERNAL_SVC_IP & 0Xffffff,
        };

To avoid the build time and run time warnings seen with a 0-sized
trailing array for struct bpf_lpm_trie_key, introduce a new struct
that correctly uses a flexible array for the trailing bytes,
struct bpf_lpm_trie_key_u8. As part of this, include the "header"
portion (which is just the "prefixlen" member), so it can be used
by anything building a bpf_lpr_trie_key that has trailing members that
aren't a u8 flexible array (like the self-test[1]), which is named
struct bpf_lpm_trie_key_hdr.

Unfortunately, C++ refuses to parse the __struct_group() helper, so
it is not possible to define struct bpf_lpm_trie_key_hdr directly in
struct bpf_lpm_trie_key_u8, so we must open-code the union directly.

Adjust the kernel code to use struct bpf_lpm_trie_key_u8 through-out,
and for the selftest to use struct bpf_lpm_trie_key_hdr. Add a comment
to the UAPI header directing folks to the two new options.

Reported-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Closes: https://paste.debian.net/hidden/ca500597/
Link: https://lore.kernel.org/all/202206281009.4332AA33@keescook/ [1]
Link: https://lore.kernel.org/bpf/20240222155612.it.533-kees@kernel.org
2024-02-29 22:52:43 +01:00
Dave Thaler
89ee838130 bpf, docs: specify which BPF_ABS and BPF_IND fields were zero
Specifying which fields were unused allows IANA to only list as deprecated
instructions that were actually used, leaving the rest as unassigned and
possibly available for future use for something else.

Signed-off-by: Dave Thaler <dthaler1968@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20240221175419.16843-1-dthaler1968@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-02-22 09:11:49 -08:00
Dave Thaler
c1bb68f6b2 bpf, docs: Fix typos in instruction-set.rst
* "BPF ADD" should be "BPF_ADD".
* "src" should be "src_reg" in several places.  The latter is the field name
  in the instruction.  The former refers to the value of the register, or the
  immediate.
* Add '' around field names in one sentence, for consistency with the rest
  of the document.

Signed-off-by: Dave Thaler <dthaler1968@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20240221173535.16601-1-dthaler1968@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-02-22 09:07:37 -08:00
Dave Thaler
dc8543b597 bpf, docs: Update ISA document title
* Use "Instruction Set Architecture (ISA)" instead of "Instruction Set
  Specification"
* Remove version number

As previously discussed on the mailing list at
https://mailarchive.ietf.org/arch/msg/bpf/SEpn3OL9TabNRn-4rDX9A6XVbjM/

Signed-off-by: Dave Thaler <dthaler1968@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20240208221449.12274-1-dthaler1968@gmail.com
2024-02-13 23:14:15 +01:00
Dave Thaler
563918a0e3 bpf, docs: Fix typos in instructions-set.rst
* "imm32" should just be "imm"
* Add blank line to fix formatting error reported by Stephen Rothwell [0]

[0]: https://lore.kernel.org/bpf/20240206153301.4ead0bad@canb.auug.org.au/T/#u

Signed-off-by: Dave Thaler <dthaler1968@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20240206045146.4965-1-dthaler1968@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-02-06 07:44:59 -08:00
Dave Thaler
2d9a925d0f bpf, docs: Expand set of initial conformance groups
This patch attempts to update the ISA specification according
to the latest mailing list discussion about conformance groups,
in a way that is intended to be consistent with IANA registry
processes and IETF 118 WG meeting discussion.

It does the following:
* Split basic into base32 and base64 for 32-bit vs 64-bit base
  instructions
* Split division/multiplication/modulo instructions out of base groups
* Split atomic instructions out of base groups

There may be additional changes as discussion continues,
but there seems to be consensus on the principles above.

v1->v2: fixed typo pointed out by David Vernet

v2->v3: Moved multiplication to same groups as division/modulo

Signed-off-by: Dave Thaler <dthaler1968@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20240202221110.3872-1-dthaler1968@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-02-05 14:44:45 -08:00
Dave Thaler
088a464ed5 bpf, docs: Clarify which legacy packet instructions existed
As discussed on the BPF IETF mailing list (see link), this patch updates
the "Legacy BPF Packet access instructions" section to clarify which
instructions are deprecated (vs which were never defined and so are not
deprecated).

Signed-off-by: Dave Thaler <dthaler1968@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Acked-by: David Vernet <void@manifault.com>
Link: https://mailarchive.ietf.org/arch/msg/bpf/5LnnKm093cGpOmDI9TnLQLBXyys
Link: https://lore.kernel.org/bpf/20240131033759.3634-1-dthaler1968@gmail.com
2024-02-01 11:32:13 +01:00
Daniel Xu
6f3189f38a bpf: treewide: Annotate BPF kfuncs in BTF
This commit marks kfuncs as such inside the .BTF_ids section. The upshot
of these annotations is that we'll be able to automatically generate
kfunc prototypes for downstream users. The process is as follows:

1. In source, use BTF_KFUNCS_START/END macro pair to mark kfuncs
2. During build, pahole injects into BTF a "bpf_kfunc" BTF_DECL_TAG for
   each function inside BTF_KFUNCS sets
3. At runtime, vmlinux or module BTF is made available in sysfs
4. At runtime, bpftool (or similar) can look at provided BTF and
   generate appropriate prototypes for functions with "bpf_kfunc" tag

To ensure future kfunc are similarly tagged, we now also return error
inside kfunc registration for untagged kfuncs. For vmlinux kfuncs,
we also WARN(), as initcall machinery does not handle errors.

Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Acked-by: Benjamin Tissoires <bentiss@kernel.org>
Link: https://lore.kernel.org/r/e55150ceecbf0a5d961e608941165c0bee7bc943.1706491398.git.dxu@dxuuu.xyz
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-01-31 20:40:56 -08:00
Yonghong Song
ced33f2cfa docs/bpf: Improve documentation of 64-bit immediate instructions
For 64-bit immediate instruction, 'BPF_IMM | BPF_DW | BPF_LD' and
src_reg=[0-6], the current documentation describes the 64-bit
immediate is constructed by:

  imm64 = (next_imm << 32) | imm

But actually imm64 is only used when src_reg=0. For all other
variants (src_reg != 0), 'imm' and 'next_imm' have separate special
encoding requirement and imm64 cannot be easily used to describe
instruction semantics.

This patch clarifies that 64-bit immediate instructions use
two 32-bit immediate values instead of a 64-bit immediate value,
so later describing individual 64-bit immediate instructions
becomes less confusing.

Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Dave Thaler <dthaler1968@gmail.com>
Link: https://lore.kernel.org/bpf/20240127194629.737589-1-yonghong.song@linux.dev
2024-01-29 16:54:33 +01:00
Dave Thaler
e48f0f4a9b bpf, docs: Clarify definitions of various instructions
Clarify definitions of several instructions:

* BPF_NEG does not support BPF_X
* BPF_CALL does not support BPF_JMP32 or BPF_X
* BPF_EXIT does not support BPF_X
* BPF_JA does not support BPF_X (was implied but not explicitly stated)

Also fix a typo in the wide instruction figure where the field is
actually named "opcode" not "code".

Signed-off-by: Dave Thaler <dthaler1968@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/bpf/20240126040050.8464-1-dthaler1968@gmail.com
2024-01-26 19:05:38 +01:00
Dave Thaler
20e109ea98 bpf, docs: Clarify that MOVSX is only for BPF_X not BPF_K
Per discussion on the mailing list at
https://mailarchive.ietf.org/arch/msg/bpf/uQiqhURdtxV_ZQOTgjCdm-seh74/
the MOVSX operation is only defined to support register extension.

The document didn't previously state this and incorrectly implied
that one could use an immediate value.

Signed-off-by: Dave Thaler <dthaler1968@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240118232954.27206-1-dthaler1968@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-01-23 15:10:08 -08:00
Yonghong Song
88031b929c docs/bpf: Fix an incorrect statement in verifier.rst
In verifier.rst, I found an incorrect statement (maybe a typo) in section
'Liveness marks tracking'. Basically, the wrong register is attributed
to have a read mark. This may confuse the user.

Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240111052136.3440417-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-01-23 14:40:23 -08:00
Dave Thaler
81777efbf5 Introduce concept of conformance groups
The discussion of what the actual conformance groups should be
is still in progress, so this is just part 1 which only uses
"legacy" for deprecated instructions and "basic" for everything
else.  Subsequent patches will add more groups as discussion
continues.

Signed-off-by: Dave Thaler <dthaler1968@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20240108214231.5280-1-dthaler1968@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-01-23 14:40:22 -08:00
Linus Torvalds
5b9b41617b Another moderately busy cycle for documentation, including:
- The minimum Sphinx requirement has been raised to 2.4.4, following a
   warning that was added in 6.2.
 
 - Some reworking of the Documentation/process front page to, hopefully,
   make it more useful.
 
 - Various kernel-doc tweaks to, for example, make it deal properly with
   __counted_by annotations.
 
 - We have also restored a warning for documentation of nonexistent
   structure members that disappeared a while back.  That had the delightful
   consequence of adding some 600 warnings to the docs build.  A sustained
   effort by Randy, Vegard, and myself has addressed almost all of those,
   bringing the documentation back into sync with the code.  The fixes are
   going through the appropriate maintainer trees.
 
 - Various improvements to the HTML rendered docs, including automatic links
   to Git revisions and a nice new pulldown to make translations easy to
   access.
 
 - Speaking of translations, more of those for Spanish and Chinese.
 
 ...plus the usual stream of documentation updates and typo fixes.
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Merge tag 'docs-6.8' of git://git.lwn.net/linux

Pull documentation update from Jonathan Corbet:
 "Another moderately busy cycle for documentation, including:

   - The minimum Sphinx requirement has been raised to 2.4.4, following
     a warning that was added in 6.2

   - Some reworking of the Documentation/process front page to,
     hopefully, make it more useful

   - Various kernel-doc tweaks to, for example, make it deal properly
     with __counted_by annotations

   - We have also restored a warning for documentation of nonexistent
     structure members that disappeared a while back. That had the
     delightful consequence of adding some 600 warnings to the docs
     build. A sustained effort by Randy, Vegard, and myself has
     addressed almost all of those, bringing the documentation back into
     sync with the code. The fixes are going through the appropriate
     maintainer trees

   - Various improvements to the HTML rendered docs, including automatic
     links to Git revisions and a nice new pulldown to make translations
     easy to access

   - Speaking of translations, more of those for Spanish and Chinese

  ... plus the usual stream of documentation updates and typo fixes"

* tag 'docs-6.8' of git://git.lwn.net/linux: (57 commits)
  MAINTAINERS: use tabs for indent of CONFIDENTIAL COMPUTING THREAT MODEL
  A reworked process/index.rst
  ring-buffer/Documentation: Add documentation on buffer_percent file
  Translated the RISC-V architecture boot documentation.
  Docs: remove mentions of fdformat from util-linux
  Docs/zh_CN: Fix the meaning of DEBUG to pr_debug()
  Documentation: move driver-api/dcdbas to userspace-api/
  Documentation: move driver-api/isapnp to userspace-api/
  Documentation/core-api : fix typo in workqueue
  Documentation/trace: Fixed typos in the ftrace FLAGS section
  kernel-doc: handle a void function without producing a warning
  scripts/get_abi.pl: ignore some temp files
  docs: kernel_abi.py: fix command injection
  scripts/get_abi: fix source path leak
  CREDITS, MAINTAINERS, docs/process/howto: Update man-pages' maintainer
  docs: translations: add translations links when they exist
  kernel-doc: Align quick help and the code
  MAINTAINERS: add reviewer for Spanish translations
  docs: ignore __counted_by attribute in structure definitions
  scripts: kernel-doc: Clarify missing struct member description
  ..
2024-01-11 19:46:52 -08:00
David Vernet
a6de18f310 bpf: Add bpf_cpumask_weight() kfunc
It can be useful to query how many bits are set in a cpumask. For
example, if you want to perform special logic for the last remaining
core that's set in a mask. Let's therefore add a new
bpf_cpumask_weight() kfunc which checks how many bits are set in a mask.

Signed-off-by: David Vernet <void@manifault.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20231207210843.168466-2-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-12-09 21:37:33 -08:00
Song Liu
0de267d9ec Documentation/bpf: Add documentation for filesystem kfuncs
Add a brief introduction for file system kfuncs:

  bpf_get_file_xattr()
  bpf_get_fsverity_digest()

The documentation highlights the strategy to avoid recursions of these
kfuncs.

Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20231129234417.856536-4-song@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-12-01 16:21:03 -08:00
Vegard Nossum
86b17aaf2e docs: automarkup: linkify git revs
There aren't a ton of references to commits in the documentation, but
they do exist, and we can use automarkup to linkify them to make them
easier to follow.

Use something like this to find references to commits:

  git grep -P 'commit.*[0-9a-f]{8,}' Documentation/

Also fix a few of these to standardize on the exact format that is
already used in changelogs.

Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20231027115420.205279-1-vegard.nossum@oracle.com
2023-11-17 13:13:24 -07:00
Song Liu
045edee19d bpf: Introduce KF_ARG_PTR_TO_CONST_STR
Similar to ARG_PTR_TO_CONST_STR for BPF helpers, KF_ARG_PTR_TO_CONST_STR
specifies kfunc args that point to const strings. Annotation "__str" is
used to specify kfunc arg of type KF_ARG_PTR_TO_CONST_STR. Also, add
documentation for the "__str" annotation.

bpf_get_file_xattr() will be the first kfunc that uses this type.

Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Link: https://lore.kernel.org/bpf/20231107045725.2278852-4-song@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-11-09 19:07:38 -08:00
Dave Marchevsky
391145ba2a bpf: Add __bpf_kfunc_{start,end}_defs macros
BPF kfuncs are meant to be called from BPF programs. Accordingly, most
kfuncs are not called from anywhere in the kernel, which the
-Wmissing-prototypes warning is unhappy about. We've peppered
__diag_ignore_all("-Wmissing-prototypes", ... everywhere kfuncs are
defined in the codebase to suppress this warning.

This patch adds two macros meant to bound one or many kfunc definitions.
All existing kfunc definitions which use these __diag calls to suppress
-Wmissing-prototypes are migrated to use the newly-introduced macros.
A new __diag_ignore_all - for "-Wmissing-declarations" - is added to the
__bpf_kfunc_start_defs macro based on feedback from Andrii on an earlier
version of this patch [0] and another recent mailing list thread [1].

In the future we might need to ignore different warnings or do other
kfunc-specific things. This change will make it easier to make such
modifications for all kfunc defs.

  [0]: https://lore.kernel.org/bpf/CAEf4BzaE5dRWtK6RPLnjTW-MW9sx9K3Fn6uwqCTChK2Dcb1Xig@mail.gmail.com/
  [1]: https://lore.kernel.org/bpf/ZT+2qCc%2FaXep0%2FLf@krava/

Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Cc: Jiri Olsa <olsajiri@gmail.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Acked-by: Yafang Shao <laoar.shao@gmail.com>
Link: https://lore.kernel.org/r/20231031215625.2343848-1-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-11-01 22:33:53 -07:00
Dave Thaler
0e133a1337 bpf, docs: Define signed modulo as using truncated division
There's different mathematical definitions (truncated, floored, rounded,
etc.) and different languages have chosen different definitions [0][1].
E.g., languages/libraries that follow Knuth use a different mathematical
definition than C uses. This patch specifies which definition BPF uses,
as verified by Eduard [2] and others.

  [0] https://en.wikipedia.org/wiki/Modulo#Variants_of_the_definition
  [1] https://torstencurdt.com/tech/posts/modulo-of-negative-numbers/
  [2] https://lore.kernel.org/bpf/57e6fefadaf3b2995bb259fa8e711c7220ce5290.camel@gmail.com/

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: David Vernet <void@manifault.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20231017203020.1500-1-dthaler1968@googlemail.com
2023-10-19 01:36:12 +02:00
Daan De Meyer
3243fef6a4 documentation/bpf: Document cgroup unix socket address hooks
Update the documentation to mention the new cgroup unix sockaddr
hooks.

Signed-off-by: Daan De Meyer <daan.j.demeyer@gmail.com>
Link: https://lore.kernel.org/r/20231011185113.140426-8-daan.j.demeyer@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-11 17:27:55 -07:00
Quan Tian
558c50cc3b docs/bpf: update out-of-date doc in BPF flow dissector
Commit a5e2151ff9 ("net/ipv6: SKB symmetric hash should incorporate
transport ports") removed the use of FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL
in __skb_get_hash_symmetric(), making the doc out-of-date.

Signed-off-by: Quan Tian <qtian@vmware.com>
Link: https://lore.kernel.org/r/20230911152353.8280-1-qtian@vmware.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-09-13 14:22:57 -07:00
Linus Torvalds
73be7fb14e Including fixes from netfilter and bpf.
Current release - regressions:
 
  - eth: stmmac: fix failure to probe without MAC interface specified
 
 Current release - new code bugs:
 
  - docs: netlink: fix missing classic_netlink doc reference
 
 Previous releases - regressions:
 
  - deal with integer overflows in kmalloc_reserve()
 
  - use sk_forward_alloc_get() in sk_get_meminfo()
 
  - bpf_sk_storage: fix the missing uncharge in sk_omem_alloc
 
  - fib: avoid warn splat in flow dissector after packet mangling
 
  - skb_segment: call zero copy functions before using skbuff frags
 
  - eth: sfc: check for zero length in EF10 RX prefix
 
 Previous releases - always broken:
 
  - af_unix: fix msg_controllen test in scm_pidfd_recv() for
    MSG_CMSG_COMPAT
 
  - xsk: fix xsk_build_skb() dereferencing possible ERR_PTR()
 
  - netfilter:
    - nft_exthdr: fix non-linear header modification
    - xt_u32, xt_sctp: validate user space input
    - nftables: exthdr: fix 4-byte stack OOB write
    - nfnetlink_osf: avoid OOB read
    - one more fix for the garbage collection work from last release
 
  - igmp: limit igmpv3_newpack() packet size to IP_MAX_MTU
 
  - bpf, sockmap: fix preempt_rt splat when using raw_spin_lock_t
 
  - handshake: fix null-deref in handshake_nl_done_doit()
 
  - ip: ignore dst hint for multipath routes to ensure packets
    are hashed across the nexthops
 
  - phy: micrel:
    - correct bit assignments for cable test errata
    - disable EEE according to the KSZ9477 errata
 
 Misc:
 
  - docs/bpf: document compile-once-run-everywhere (CO-RE) relocations
 
  - Revert "net: macsec: preserve ingress frame ordering", it appears
    to have been developed against an older kernel, problem doesn't
    exist upstream
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking updates from Jakub Kicinski:
 "Including fixes from netfilter and bpf.

  Current release - regressions:

   - eth: stmmac: fix failure to probe without MAC interface specified

  Current release - new code bugs:

   - docs: netlink: fix missing classic_netlink doc reference

  Previous releases - regressions:

   - deal with integer overflows in kmalloc_reserve()

   - use sk_forward_alloc_get() in sk_get_meminfo()

   - bpf_sk_storage: fix the missing uncharge in sk_omem_alloc

   - fib: avoid warn splat in flow dissector after packet mangling

   - skb_segment: call zero copy functions before using skbuff frags

   - eth: sfc: check for zero length in EF10 RX prefix

  Previous releases - always broken:

   - af_unix: fix msg_controllen test in scm_pidfd_recv() for
     MSG_CMSG_COMPAT

   - xsk: fix xsk_build_skb() dereferencing possible ERR_PTR()

   - netfilter:
      - nft_exthdr: fix non-linear header modification
      - xt_u32, xt_sctp: validate user space input
      - nftables: exthdr: fix 4-byte stack OOB write
      - nfnetlink_osf: avoid OOB read
      - one more fix for the garbage collection work from last release

   - igmp: limit igmpv3_newpack() packet size to IP_MAX_MTU

   - bpf, sockmap: fix preempt_rt splat when using raw_spin_lock_t

   - handshake: fix null-deref in handshake_nl_done_doit()

   - ip: ignore dst hint for multipath routes to ensure packets are
     hashed across the nexthops

   - phy: micrel:
      - correct bit assignments for cable test errata
      - disable EEE according to the KSZ9477 errata

  Misc:

   - docs/bpf: document compile-once-run-everywhere (CO-RE) relocations

   - Revert "net: macsec: preserve ingress frame ordering", it appears
     to have been developed against an older kernel, problem doesn't
     exist upstream"

* tag 'net-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (95 commits)
  net: enetc: distinguish error from valid pointers in enetc_fixup_clear_rss_rfs()
  Revert "net: team: do not use dynamic lockdep key"
  net: hns3: remove GSO partial feature bit
  net: hns3: fix the port information display when sfp is absent
  net: hns3: fix invalid mutex between tc qdisc and dcb ets command issue
  net: hns3: fix debugfs concurrency issue between kfree buffer and read
  net: hns3: fix byte order conversion issue in hclge_dbg_fd_tcam_read()
  net: hns3: Support query tx timeout threshold by debugfs
  net: hns3: fix tx timeout issue
  net: phy: Provide Module 4 KSZ9477 errata (DS80000754C)
  netfilter: nf_tables: Unbreak audit log reset
  netfilter: ipset: add the missing IP_SET_HASH_WITH_NET0 macro for ip_set_hash_netportnet.c
  netfilter: nft_set_rbtree: skip sync GC for new elements in this transaction
  netfilter: nf_tables: uapi: Describe NFTA_RULE_CHAIN_ID
  netfilter: nfnetlink_osf: avoid OOB read
  netfilter: nftables: exthdr: fix 4-byte stack OOB write
  selftests/bpf: Check bpf_sk_storage has uncharged sk_omem_alloc
  bpf: bpf_sk_storage: Fix the missing uncharge in sk_omem_alloc
  bpf: bpf_sk_storage: Fix invalid wait context lockdep report
  s390/bpf: Pass through tail call counter in trampolines
  ...
2023-09-07 18:33:07 -07:00
Eduard Zingerman
3888fa134e docs/bpf: Fix "file doesn't exist" warnings in {llvm_reloc,btf}.rst
scripts/documentation-file-ref-check reports warnings for (valid) cross-links
of form:

  :ref:`Documentation/bpf/btf <BTF_Ext_Section>`

Adding extension to the file name helps to avoid the warning, e.g:

  :ref:`Documentation/bpf/btf.rst <BTF_Ext_Section>`

Fixes: be4033d360 ("docs/bpf: Add description for CO-RE relocations")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Closes: https://lore.kernel.org/oe-kbuild-all/202309010804.G3MpXo59-lkp@intel.com
Link: https://lore.kernel.org/bpf/20230901125935.487972-1-eddyz87@gmail.com
2023-09-01 15:56:48 +02:00
Linus Torvalds
cd99b9eb4b Documentation work keeps chugging along; stuff for 6.6 includes:
- Work from Carlos Bilbao to integrate rustdoc output into the generated
   HTML documentation.  This took some work to figure out how to do it
   without slowing the docs build and without creating people who don't have
   Rust installed, but Carlos got there.
 
 - Move the loongarch and mips architecture documentation under
   Documentation/arch/.
 
 - Some more maintainer documentation from Jakub
 
 ...plus the usual assortment of updates, translations, and fixes.
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Merge tag 'docs-6.6' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "Documentation work keeps chugging along; this includes:

   - Work from Carlos Bilbao to integrate rustdoc output into the
     generated HTML documentation. This took some work to figure out how
     to do it without slowing the docs build and without creating people
     who don't have Rust installed, but Carlos got there

   - Move the loongarch and mips architecture documentation under
     Documentation/arch/

   - Some more maintainer documentation from Jakub

  ... plus the usual assortment of updates, translations, and fixes"

* tag 'docs-6.6' of git://git.lwn.net/linux: (56 commits)
  Docu: genericirq.rst: fix irq-example
  input: docs: pxrc: remove reference to phoenix-sim
  Documentation: serial-console: Fix literal block marker
  docs/mm: remove references to hmm_mirror ops and clean typos
  docs/zh_CN: correct regi_chg(),regi_add() to region_chg(),region_add()
  Documentation: Fix typos
  Documentation/ABI: Fix typos
  scripts: kernel-doc: fix macro handling in enums
  scripts: kernel-doc: parse DEFINE_DMA_UNMAP_[ADDR|LEN]
  Documentation: riscv: Update boot image header since EFI stub is supported
  Documentation: riscv: Add early boot document
  Documentation: arm: Add bootargs to the table of added DT parameters
  docs: kernel-parameters: Refer to the correct bitmap function
  doc: update params of memhp_default_state=
  docs: Add book to process/kernel-docs.rst
  docs: sparse: fix invalid link addresses
  docs: vfs: clean up after the iterate() removal
  docs: Add a section on surveys to the researcher guidelines
  docs: move mips under arch
  docs: move loongarch under arch
  ...
2023-08-30 20:05:42 -07:00
David Vernet
7d35eb1a18 bpf, docs: s/eBPF/BPF in standards documents
There isn't really anything other than just "BPF" at this point,
so referring to it as "eBPF" in our standards document just causes
unnecessary confusion. Let's just be consistent and use "BPF".

Suggested-by: Will Hawkins <hawkinsw@obs.cr>
Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230828155948.123405-4-void@manifault.com
2023-08-30 16:36:10 +02:00
David Vernet
deb8840725 bpf, docs: Add abi.rst document to standardization subdirectory
As specified in the IETF BPF charter, the BPF working group has plans to
add one or more informational documents that recommend conventions and
guidelines for producing portable BPF program binaries. The
instruction-set.rst document currently contains a "Registers and calling
convention" subsection which dictates a calling convention that belongs
in an ABI document, rather than an instruction set document. Let's move
it to a new abi.rst document so we can clean it up. The abi.rst document
will of course be significantly changed and expanded upon over time. For
now, it's really just a placeholder which will contain ABI-specific
language that doesn't belong in other documents.

Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230828155948.123405-3-void@manifault.com
2023-08-30 16:35:58 +02:00
David Vernet
aee1720eeb bpf, docs: Move linux-notes.rst to root bpf docs tree
In commit 4d496be9ca ("bpf,docs: Create new standardization
subdirectory"), I added a standardization/ directory to the BPF
documentation, which will contain the docs that will be standardized
as part of the effort with the IETF.

I included linux-notes.rst in that directory, but I shouldn't have. It
doesn't contain anything that will be standardized. Let's move it back
to Documentation/bpf.

Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230828155948.123405-2-void@manifault.com
2023-08-30 16:35:44 +02:00
Eduard Zingerman
be4033d360 docs/bpf: Add description for CO-RE relocations
Add a section on CO-RE relocations to llvm_relo.rst. Describe relevant .BTF.ext
structure, `enum bpf_core_relo_kind` and `struct bpf_core_relo` in some detail.

Description is based on doc-strings from:

  - include/uapi/linux/bpf.h:struct bpf_core_relo
  - tools/lib/bpf/relo_core.c:__bpf_core_types_match()

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/bpf/20230826222912.2560865-2-eddyz87@gmail.com
2023-08-30 09:53:02 +02:00
Will Hawkins
2d71a90f7e bpf, docs: Correct source of offset for program-local call
The offset to use when calculating the target of a program-local call is
in the instruction's imm field, not its offset field.

Signed-off-by: Will Hawkins <hawkinsw@obs.cr>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20230826053258.1860167-1-hawkinsw@obs.cr
2023-08-30 09:49:53 +02:00
Bjorn Helgaas
d56b699d76 Documentation: Fix typos
Fix typos in Documentation.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20230814212822.193684-4-helgaas@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-08-18 11:29:03 -06:00
Will Hawkins
e546a11980 bpf, docs: Fix small typo and define semantics of sign extension
Add additional precision on the semantics of the sign extension
operations in BPF. In addition, fix a very minor typo.

Signed-off-by: Will Hawkins <hawkinsw@obs.cr>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230808212503.197834-1-hawkinsw@obs.cr
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-08-08 16:29:20 -07:00
Will Hawkins
2369e52657 bpf, docs: Formalize type notation and function semantics in ISA standard
Give a single place where the shorthand for types are defined and the
semantics of helper functions are described.

Signed-off-by: Will Hawkins <hawkinsw@obs.cr>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230807140651.122484-1-hawkinsw@obs.cr
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-08-07 15:13:26 -07:00
Yonghong Song
fb213ecbb8 docs/bpf: Fix malformed documentation
Two issues are fixed:
  1. Malformed table due to newly-introduced BPF_MOVSX
  2. Missing reference link for ``Sign-extension load operations``

Fixes: 245d4c40c0 ("docs/bpf: Add documentation for new instructions")
Cc: bpf@ietf.org
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202307291840.Cqhj7uox-lkp@intel.com/
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20230730004251.381307-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-29 18:57:51 -07:00