linux-stable.git/Documentation/bpf, branch v5.2

bpf: btf: fix the brackets of BTF_INT_OFFSET()

2019-05-14T08:05:18+00:00

'VAL' should be protected by the brackets.

v2:
* Squash the fix for Documentation/bpf/btf.rst

Fixes: 69b693f0aefa ("bpf: btf: Introduce BPF Type Format (BTF)")
Signed-off-by: Gary Lin 
Signed-off-by: Daniel Borkmann

docs/btf: fix the missing section marks

2019-05-09T22:59:59+00:00

The section titles of 3.4 and 3.5 are not marked correctly.

Signed-off-by: Gary Lin 
Signed-off-by: Alexei Starovoitov

bpf: document the verifier limits

2019-04-22T22:39:12+00:00

Document the verifier limits.

Signed-off-by: Alexei Starovoitov 
Acked-by: Yonghong Song 
Signed-off-by: Daniel Borkmann

bpf: move BPF_PROG_TYPE_FLOW_DISSECTOR documentation to a new common place

2019-04-18T23:59:42+00:00

In commit da7031491786 ("bpf: Document BPF_PROG_TYPE_CGROUP_SYSCTL")
Andrey proposes to put per-prog type docs under Documentation/bpf/

Let's move flow dissector documentation there as well.

Signed-off-by: Stanislav Fomichev 
Signed-off-by: Alexei Starovoitov

bpf: Document BPF_PROG_TYPE_CGROUP_SYSCTL

2019-04-18T23:05:36+00:00

Add documentation for BPF_PROG_TYPE_CGROUP_SYSCTL, including general
info, attach type, context, return code, helpers, example and usage
considerations.

A separate file prog_cgroup_sysctl.rst is added to Documentation/bpf/.

In the future more program types can be documented in their own
prog_.rst files.

Another way to place program type specific documentation would be to
group program types somehow (e.g. cgroup.rst for all cgroup-bpf
programs), but it may not scale well since some program types may belong
to different groups, e.g. BPF_PROG_TYPE_CGROUP_SKB can be documented
together with either cgroup-bpf programs or programs that access skb.

The new file is added to the index and verified by `make htmldocs` /
sanity-check by lynx.

Signed-off-by: Andrey Ignatov 
Acked-by: Yonghong Song 
Signed-off-by: Alexei Starovoitov

Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

2019-04-12T00:00:05+00:00

Daniel Borkmann says:

====================
pull-request: bpf-next 2019-04-12

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Improve BPF verifier scalability for large programs through two
   optimizations: i) remove verifier states that are not useful in pruning,
   ii) stop walking parentage chain once first LIVE_READ is seen. Combined
   gives approx 20x speedup. Increase limits for accepting large programs
   under root, and add various stress tests, from Alexei.

2) Implement global data support in BPF. This enables static global variables
   for .data, .rodata and .bss sections to be properly handled which allows
   for more natural program development. This also opens up the possibility
   to optimize program workflow by compiling ELFs only once and later only
   rewriting section data before reload, from Daniel and with test cases and
   libbpf refactoring from Joe.

3) Add config option to generate BTF type info for vmlinux as part of the
   kernel build process. DWARF debug info is converted via pahole to BTF.
   Latter relies on libbpf and makes use of BTF deduplication algorithm which
   results in 100x savings compared to DWARF data. Resulting .BTF section is
   typically about 2MB in size, from Andrii.

4) Add BPF verifier support for stack access with variable offset from
   helpers and add various test cases along with it, from Andrey.

5) Extend bpf_skb_adjust_room() growth BPF helper to mark inner MAC header
   so that L2 encapsulation can be used for tc tunnels, from Alan.

6) Add support for input __sk_buff context in BPF_PROG_TEST_RUN so that
   users can define a subset of allowed __sk_buff fields that get fed into
   the test program, from Stanislav.

7) Add bpf fs multi-dimensional array tests for BTF test suite and fix up
   various UBSAN warnings in bpftool, from Yonghong.

8) Generate a pkg-config file for libbpf, from Luca.

9) Dump program's BTF id in bpftool, from Prashant.

10) libbpf fix to use smaller BPF log buffer size for AF_XDP's XDP
    program, from Magnus.

11) kallsyms related fixes for the case when symbols are not present in
    BPF selftests and samples, from Daniel
====================

Signed-off-by: David S. Miller

bpf: add specification for BTF Var and DataSec kinds

2019-04-10T00:05:46+00:00

This adds the BTF specification and UAPI bits for supporting BTF Var
and DataSec kinds. This is following LLVM upstream commit ac4082b77e07
("[BPF] Add BTF Var and DataSec Support") which has been merged recently.
Var itself is for describing a global variable and DataSec to describe
ELF sections e.g. data/bss/rodata sections that hold one or multiple
global variables.

Signed-off-by: Daniel Borkmann 
Acked-by: Martin KaFai Lau 
Signed-off-by: Alexei Starovoitov

bpf, doc: fix BTF docs reflow of bullet list

2019-03-26T20:13:42+00:00

Section 2.2.1 BTF_KIND_INT a bullet list was collapsed due to
text reflow in commit 9ab5305dbe3f ("docs/btf: reflow text to
fill up to 78 characters").

This patch correct the mistake. Also adjust next bullet list,
which is used for comparison, to get rendered the same way.

Fixes: 9ab5305dbe3f ("docs/btf: reflow text to fill up to 78 characters")
Link: https://www.kernel.org/doc/html/latest/bpf/btf.html#btf-kind-int
Signed-off-by: Jesper Dangaard Brouer 
Acked-by: Andrii Nakryiko 
Signed-off-by: Alexei Starovoitov

docs/bpf: minor casing/punctuation fixes

2019-03-01T23:40:04+00:00

Fix few casing and punctuation glitches.

Signed-off-by: Andrii Nakryiko 
Signed-off-by: Daniel Borkmann

docs/btf: reflow text to fill up to 78 characters

2019-03-01T23:40:04+00:00

Reflow paragraphs to more fully and evenly fill 78 character lines.

Signed-off-by: Andrii Nakryiko 
Acked-by: Yonghong Song 
Signed-off-by: Daniel Borkmann