Commit Graph

275 Commits

Author SHA1 Message Date
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
Yonghong Song
ee932bf940 docs/bpf: Improve documentation for cpu=v4 instructions
Improve documentation for cpu=v4 instructions based on
David's suggestions.

Cc: bpf@ietf.org
Suggested-by: David Vernet <void@manifault.com>
Acked-by: David Vernet <void@manifault.com>
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20230728225105.919595-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-28 16:50:06 -07:00
Yonghong Song
245d4c40c0 docs/bpf: Add documentation for new instructions
Add documentation in instruction-set.rst for new instruction encoding
and their corresponding operations. Also removed the question
related to 'no BPF_SDIV' in bpf_design_QA.rst since we have
BPF_SDIV insn now.

Cc: bpf@ietf.org
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20230728011342.3724411-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-27 18:54:17 -07:00
Jose E. Marchesi
10d78a66a5 bpf, docs: fix BPF_NEG entry in instruction-set.rst
This patch fixes the documentation of the BPF_NEG instruction to
denote that it does not use the source register operand.

Signed-off-by: Jose E. Marchesi <jose.marchesi@oracle.com>
Acked-by: Dave Thaler <dthaler@microsoft.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20230726092543.6362-1-jose.marchesi@oracle.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-27 17:31:49 -07:00
David Vernet
4d496be9ca bpf,docs: Create new standardization subdirectory
The BPF standardization effort is actively underway with the IETF. As
described in the BPF Working Group (WG) charter in [0], there are a
number of proposed documents, some informational and some proposed
standards, that will be drafted as part of the standardization effort.

[0]: https://datatracker.ietf.org/wg/bpf/about/

Though the specific documents that will formally be standardized will
exist as Internet Drafts (I-D) and WG documents in the BPF WG
datatracker page, the source of truth from where those documents will be
generated will reside in the kernel documentation tree (originating in
the bpf-next tree).

Because these documents will be used to generate the I-D and WG
documents which will be standardized with the IETF, they are a bit
special as far as kernel-tree documentation goes:

- They will be dual licensed with LGPL-2.1 OR BSD-2-Clause
- IETF I-D and WG documents (the documents which will actually be
  standardized) will be auto-generated from these documents.

In order to keep things clearly organized in the BPF documentation tree,
and to make it abundantly clear where standards-related documentation
needs to go, we should move standards-relevant documents into a separate
standardization/ subdirectory.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230710183027.15132-1-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-10 18:12:50 -07:00
Dave Thaler
85b0c6d490 bpf, docs: Fix definition of BPF_NEG operation
Instruction is an arithmetic negative, not a bitwise inverse.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20230627213912.951-1-dthaler1968@googlemail.com
2023-06-29 15:58:50 +02:00
Fangrui Song
bbaf1ff06a bpf: Replace deprecated -target with --target= for Clang
The -target option has been deprecated since clang 3.4 in 2013. Therefore, use
the preferred --target=bpf form instead. This also matches how we use --target=
in scripts/Makefile.clang.

Signed-off-by: Fangrui Song <maskray@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: 274b6f0c87
Link: https://lore.kernel.org/bpf/20230624001856.1903733-1-maskray@google.com
2023-06-29 15:46:17 +02:00
David Howells
dc97391e66 sock: Remove ->sendpage*() in favour of sendmsg(MSG_SPLICE_PAGES)
Remove ->sendpage() and ->sendpage_locked().  sendmsg() with
MSG_SPLICE_PAGES should be used instead.  This allows multiple pages and
multipage folios to be passed through.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> # for net/can
cc: Jens Axboe <axboe@kernel.dk>
cc: Matthew Wilcox <willy@infradead.org>
cc: linux-afs@lists.infradead.org
cc: mptcp@lists.linux.dev
cc: rds-devel@oss.oracle.com
cc: tipc-discussion@lists.sourceforge.net
cc: virtualization@lists.linux-foundation.org
Link: https://lore.kernel.org/r/20230623225513.2732256-16-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-24 15:50:13 -07:00
Anton Protopopov
fbc5669de6 bpf, docs: Document existing macros instead of deprecated
The BTF_TYPE_SAFE_NESTED macro was replaced by the BTF_TYPE_SAFE_TRUSTED,
BTF_TYPE_SAFE_RCU, and BTF_TYPE_SAFE_RCU_OR_NULL macros. Fix the docs
correspondingly.

Fixes: 6fcd486b3a ("bpf: Refactor RCU enforcement in the verifier.")
Signed-off-by: Anton Protopopov <aspsk@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20230622095424.1024244-1-aspsk@isovalent.com
2023-06-22 19:47:32 +02:00
Anton Protopopov
2404dd01b5 bpf, docs: BPF Iterator Document
Fix the description of the seq_info field of the bpf_iter_reg structure which
was wrong due to an accidental copy/paste of the previous field's description.

Fixes: 8972e18a43 ("bpf, docs: BPF Iterator Document")
Signed-off-by: Anton Protopopov <aspsk@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20230622095407.1024053-1-aspsk@isovalent.com
2023-06-22 19:44:22 +02:00
David Vernet
25085b4e92 bpf/docs: Update documentation for new cpumask kfuncs
We recently added the bpf_cpumask_first_and() kfunc, and changed
bpf_cpumask_any() / bpf_cpumask_any_and() to
bpf_cpumask_any_distribute() and bpf_cpumask_any_distribute_and()
respectively. This patch adds an entry for the bpf_cpumask_first_and()
kfunc, and updates the documentation for the *any* kfuncs to the new
names.

Signed-off-by: David Vernet <void@manifault.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20230610035053.117605-5-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-06-12 15:09:11 -07:00
Dave Thaler
8819495a75 bpf, docs: Shift operations are defined to use a mask
Update the documentation regarding shift operations to explain the
use of a mask, since otherwise shifting by a value out of range
(like negative) is undefined.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20230509180845.1236-1-dthaler1968@googlemail.com
2023-05-17 16:18:33 +02:00
Jakub Kicinski
a0e35a648f bpf-next-for-netdev
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
pull-request: bpf-next 2023-05-16

We've added 57 non-merge commits during the last 19 day(s) which contain
a total of 63 files changed, 3293 insertions(+), 690 deletions(-).

The main changes are:

1) Add precision propagation to verifier for subprogs and callbacks,
   from Andrii Nakryiko.

2) Improve BPF's {g,s}setsockopt() handling with wrong option lengths,
   from Stanislav Fomichev.

3) Utilize pahole v1.25 for the kernel's BTF generation to filter out
   inconsistent function prototypes, from Alan Maguire.

4) Various dyn-pointer verifier improvements to relax restrictions,
   from Daniel Rosenberg.

5) Add a new bpf_task_under_cgroup() kfunc for designated task,
   from Feng Zhou.

6) Unblock tests for arm64 BPF CI after ftrace supporting direct call,
   from Florent Revest.

7) Add XDP hint kfunc metadata for RX hash/timestamp for igc,
   from Jesper Dangaard Brouer.

8) Add several new dyn-pointer kfuncs to ease their usability,
   from Joanne Koong.

9) Add in-depth LRU internals description and dot function graph,
   from Joe Stringer.

10) Fix KCSAN report on bpf_lru_list when accessing node->ref,
    from Martin KaFai Lau.

11) Only dump unprivileged_bpf_disabled log warning upon write,
    from Kui-Feng Lee.

12) Extend test_progs to directly passing allow/denylist file,
    from Stephen Veiss.

13) Fix BPF trampoline memleak upon failure attaching to fentry,
    from Yafang Shao.

14) Fix emitting struct bpf_tcp_sock type in vmlinux BTF,
    from Yonghong Song.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (57 commits)
  bpf: Fix memleak due to fentry attach failure
  bpf: Remove bpf trampoline selector
  bpf, arm64: Support struct arguments in the BPF trampoline
  bpftool: JIT limited misreported as negative value on aarch64
  bpf: fix calculation of subseq_idx during precision backtracking
  bpf: Remove anonymous union in bpf_kfunc_call_arg_meta
  bpf: Document EFAULT changes for sockopt
  selftests/bpf: Correctly handle optlen > 4096
  selftests/bpf: Update EFAULT {g,s}etsockopt selftests
  bpf: Don't EFAULT for {g,s}setsockopt with wrong optlen
  libbpf: fix offsetof() and container_of() to work with CO-RE
  bpf: Address KCSAN report on bpf_lru_list
  bpf: Add --skip_encoding_btf_inconsistent_proto, --btf_gen_optimized to pahole flags for v1.25
  selftests/bpf: Accept mem from dynptr in helper funcs
  bpf: verifier: Accept dynptr mem as mem in helpers
  selftests/bpf: Check overflow in optional buffer
  selftests/bpf: Test allowing NULL buffer in dynptr slice
  bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)
  selftests/bpf: Add testcase for bpf_task_under_cgroup
  bpf: Add bpf_task_under_cgroup() kfunc
  ...
====================

Link: https://lore.kernel.org/r/20230515225603.27027-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-16 19:50:05 -07:00
Stanislav Fomichev
6b6a23d5d8 bpf: Document EFAULT changes for sockopt
And add examples for how to correctly handle large optlens.
This is less relevant now when we don't EFAULT anymore, but
that's still the correct thing to do.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20230511170456.1759459-5-sdf@google.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-05-13 16:55:46 -07:00
Daniel Rosenberg
3bda08b636 bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)
bpf_dynptr_slice(_rw) uses a user provided buffer if it can not provide
a pointer to a block of contiguous memory. This buffer is unused in the
case of local dynptrs, and may be unused in other cases as well. There
is no need to require the buffer, as the kfunc can just return NULL if
it was needed and not provided.

This adds another kfunc annotation, __opt, which combines with __sz and
__szk to allow the buffer associated with the size to be NULL. If the
buffer is NULL, the verifier does not check that the buffer is of
sufficient size.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Link: https://lore.kernel.org/r/20230506013134.2492210-2-drosen@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-06 16:42:57 -07:00
Will Hawkins
6953518629 bpf, docs: Update llvm_relocs.rst with typo fixes
Correct a few typographical errors and fix some mistakes in examples.

Signed-off-by: Will Hawkins <hawkinsw@obs.cr>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20230428023015.1698072-2-hawkinsw@obs.cr
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-05-05 08:20:39 -07:00
Linus Torvalds
8c1318e438 lsm/stable-6.4 PR 20230428
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Merge tag 'lsm-pr-20230428' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm

Pull lsm fix from Paul Moore:
 "A single Documentation/LSM fix to update the LSM hook documentation
  references from lsm_hooks.h to security.c"

* tag 'lsm-pr-20230428' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm:
  lsm: move hook comments docs to security/security.c
2023-04-29 10:17:05 -07:00
Randy Dunlap
6d2ed65318 lsm: move hook comments docs to security/security.c
Fix one kernel-doc warning, but invesigating that led to other
kernel-doc movement (lsm_hooks.h to security.c) that needs to be
fixed also.

include/linux/lsm_hooks.h:1: warning: no structured comments found

Fixes: e261301c85 ("lsm: move the remaining LSM hook comments to security/security.c")
Fixes: 1cd2aca64a ("lsm: move the io_uring hook comments to security/security.c")
Fixes: 452b670c72 ("lsm: move the perf hook comments to security/security.c")
Fixes: 55e853201a ("lsm: move the bpf hook comments to security/security.c")
Fixes: b14faf9c94 ("lsm: move the audit hook comments to security/security.c")
Fixes: 1427ddbe5c ("lsm: move the binder hook comments to security/security.c")
Fixes: 43fad28218 ("lsm: move the sysv hook comments to security/security.c")
Fixes: ecc419a445 ("lsm: move the key hook comments to security/security.c")
Fixes: 742b99456e ("lsm: move the xfrm hook comments to security/security.c")
Fixes: ac318aed54 ("lsm: move the Infiniband hook comments to security/security.c")
Fixes: 4a49f592e9 ("lsm: move the SCTP hook comments to security/security.c")
Fixes: 6b6bbe8c02 ("lsm: move the socket hook comments to security/security.c")
Fixes: 2c2442fd46 ("lsm: move the AF_UNIX hook comments to security/security.c")
Fixes: 2bcf51bf2f ("lsm: move the netlink hook comments to security/security.c")
Fixes: 130c53bfee ("lsm: move the task hook comments to security/security.c")
Fixes: a0fd6480de ("lsm: move the file hook comments to security/security.c")
Fixes: 9348944b77 ("lsm: move the kernfs hook comments to security/security.c")
Fixes: 916e32584d ("lsm: move the inode hook comments to security/security.c")
Fixes: 08526a902c ("lsm: move the filesystem hook comments to security/security.c")
Fixes: 36819f1855 ("lsm: move the fs_context hook comments to security/security.c")
Fixes: 1661372c91 ("lsm: move the program execution hook comments to security/security.c")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Paul Moore <paul@paul-moore.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: linux-security-module@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: KP Singh <kpsingh@kernel.org>
Cc: bpf@vger.kernel.org
Signed-off-by: Paul Moore <paul@paul-moore.com>
2023-04-28 11:58:34 -04:00
Joe Stringer
1a986518b8 docs/bpf: Add LRU internals description and graph
Extend the bpf hashmap docs to include a brief description of the
internals of the LRU map type (setting appropriate API expectations),
including the original commit message from Martin and a variant on the
graph that I had presented during my Linux Plumbers Conference 2022
talk on "Pressure feedback for LRU map types"[0].

The node names in the dot file correspond roughly to the functions
where the logic for those decisions or steps is defined, to help
curious developers to cross-reference and update this logic if the
details of the LRU implementation ever differ from this description.

  [0] https://lpc.events/event/16/contributions/1368/

Signed-off-by: Joe Stringer <joe@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20230422172054.3355436-2-joe@isovalent.com
2023-04-27 14:20:44 +02:00
Joe Stringer
af0335d292 docs/bpf: Add table to describe LRU properties
Depending on the map type and flags for LRU, different properties are
global or percpu. Add a table to describe these.

Signed-off-by: Joe Stringer <joe@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20230422172054.3355436-1-joe@isovalent.com
2023-04-27 14:20:29 +02:00
David Vernet
530474e6d0 bpf,docs: Remove KF_KPTR_GET from documentation
A prior patch removed KF_KPTR_GET from the kernel. Now that it's no
longer accessible to kfunc authors, this patch removes it from the BPF
kfunc documentation.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230416084928.326135-4-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-16 08:51:24 -07:00
Jakub Kicinski
c2865b1122 bpf-next-for-netdev
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Daniel Borkmann says:

====================
pull-request: bpf-next 2023-04-13

We've added 260 non-merge commits during the last 36 day(s) which contain
a total of 356 files changed, 21786 insertions(+), 11275 deletions(-).

The main changes are:

1) Rework BPF verifier log behavior and implement it as a rotating log
   by default with the option to retain old-style fixed log behavior,
   from Andrii Nakryiko.

2) Adds support for using {FOU,GUE} encap with an ipip device operating
   in collect_md mode and add a set of BPF kfuncs for controlling encap
   params, from Christian Ehrig.

3) Allow BPF programs to detect at load time whether a particular kfunc
   exists or not, and also add support for this in light skeleton,
   from Alexei Starovoitov.

4) Optimize hashmap lookups when key size is multiple of 4,
   from Anton Protopopov.

5) Enable RCU semantics for task BPF kptrs and allow referenced kptr
   tasks to be stored in BPF maps, from David Vernet.

6) Add support for stashing local BPF kptr into a map value via
   bpf_kptr_xchg(). This is useful e.g. for rbtree node creation
   for new cgroups, from Dave Marchevsky.

7) Fix BTF handling of is_int_ptr to skip modifiers to work around
   tracing issues where a program cannot be attached, from Feng Zhou.

8) Migrate a big portion of test_verifier unit tests over to
   test_progs -a verifier_* via inline asm to ease {read,debug}ability,
   from Eduard Zingerman.

9) Several updates to the instruction-set.rst documentation
   which is subject to future IETF standardization
   (https://lwn.net/Articles/926882/), from Dave Thaler.

10) Fix BPF verifier in the __reg_bound_offset's 64->32 tnum sub-register
    known bits information propagation, from Daniel Borkmann.

11) Add skb bitfield compaction work related to BPF with the overall goal
    to make more of the sk_buff bits optional, from Jakub Kicinski.

12) BPF selftest cleanups for build id extraction which stand on its own
    from the upcoming integration work of build id into struct file object,
    from Jiri Olsa.

13) Add fixes and optimizations for xsk descriptor validation and several
    selftest improvements for xsk sockets, from Kal Conley.

14) Add BPF links for struct_ops and enable switching implementations
    of BPF TCP cong-ctls under a given name by replacing backing
    struct_ops map, from Kui-Feng Lee.

15) Remove a misleading BPF verifier env->bypass_spec_v1 check on variable
    offset stack read as earlier Spectre checks cover this,
    from Luis Gerhorst.

16) Fix issues in copy_from_user_nofault() for BPF and other tracers
    to resemble copy_from_user_nmi() from safety PoV, from Florian Lehner
    and Alexei Starovoitov.

17) Add --json-summary option to test_progs in order for CI tooling to
    ease parsing of test results, from Manu Bretelle.

18) Batch of improvements and refactoring to prep for upcoming
    bpf_local_storage conversion to bpf_mem_cache_{alloc,free} allocator,
    from Martin KaFai Lau.

19) Improve bpftool's visual program dump which produces the control
    flow graph in a DOT format by adding C source inline annotations,
    from Quentin Monnet.

20) Fix attaching fentry/fexit/fmod_ret/lsm to modules by extracting
    the module name from BTF of the target and searching kallsyms of
    the correct module, from Viktor Malik.

21) Improve BPF verifier handling of '<const> <cond> <non_const>'
    to better detect whether in particular jmp32 branches are taken,
    from Yonghong Song.

22) Allow BPF TCP cong-ctls to write app_limited of struct tcp_sock.
    A built-in cc or one from a kernel module is already able to write
    to app_limited, from Yixin Shen.

Conflicts:

Documentation/bpf/bpf_devel_QA.rst
  b7abcd9c65 ("bpf, doc: Link to submitting-patches.rst for general patch submission info")
  0f10f647f4 ("bpf, docs: Use internal linking for link to netdev subsystem doc")
https://lore.kernel.org/all/20230307095812.236eb1be@canb.auug.org.au/

include/net/ip_tunnels.h
  bc9d003dc4 ("ip_tunnel: Preserve pointer const in ip_tunnel_info_opts")
  ac931d4cde ("ipip,ip_tunnel,sit: Add FOU support for externally controlled ipip devices")
https://lore.kernel.org/all/20230413161235.4093777-1-broonie@kernel.org/

net/bpf/test_run.c
  e5995bc7e2 ("bpf, test_run: fix crashes due to XDP frame overwriting/corruption")
  294635a816 ("bpf, test_run: fix &xdp_frame misplacement for LIVE_FRAMES")
https://lore.kernel.org/all/20230320102619.05b80a98@canb.auug.org.au/
====================

Link: https://lore.kernel.org/r/20230413191525.7295-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-13 16:43:38 -07:00
David Vernet
ec48599abe bpf,docs: Remove references to bpf_cgroup_kptr_get()
The bpf_cgroup_kptr_get() kfunc has been removed, and
bpf_cgroup_acquire() / bpf_cgroup_release() now have the same semantics
as bpf_task_acquire() / bpf_task_release(). This patch updates the BPF
documentation to reflect this.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230411041633.179404-3-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-12 12:57:54 -07:00
Dave Thaler
16b7c970cc bpf, docs: Add docs on extended 64-bit immediate instructions
Add docs on extended 64-bit immediate instructions, including six instructions
previously undocumented.  Include a brief description of maps and variables,
as used by those instructions.

V1 -> V2: rebased on top of latest master

V2 -> V3: addressed comments from Alexei

V3 -> V4: addressed comments from David Vernet

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Link: https://lore.kernel.org/r/20230326054946.2331-1-dthaler1968@googlemail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-02 17:02:54 -07:00
David Vernet
db9d479ab5 bpf,docs: Update documentation to reflect new task kfuncs
Now that struct task_struct objects are RCU safe, and bpf_task_acquire()
can return NULL, we should update the BPF task kfunc documentation to
reflect the current state of the API.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230331195733.699708-4-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-01 09:07:20 -07:00
Dave Thaler
8cfee11071 bpf, docs: Add extended call instructions
Add extended call instructions.  Uses the term "program-local" for
call by offset.  And there are instructions for calling helper functions
by "address" (the old way of using integer values), and for calling
helper functions by BTF ID (for kfuncs).

V1 -> V2: addressed comments from David Vernet

V2 -> V3: make descriptions in table consistent with updated names

V3 -> V4: addressed comments from Alexei

V4 -> V5: fixed alignment

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230326033117.1075-1-dthaler1968@googlemail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 20:58:36 -07:00
David Vernet
6c831c4684 bpf: Treat KF_RELEASE kfuncs as KF_TRUSTED_ARGS
KF_RELEASE kfuncs are not currently treated as having KF_TRUSTED_ARGS,
even though they have a superset of the requirements of KF_TRUSTED_ARGS.
Like KF_TRUSTED_ARGS, KF_RELEASE kfuncs require a 0-offset argument, and
don't allow NULL-able arguments. Unlike KF_TRUSTED_ARGS which require
_either_ an argument with ref_obj_id > 0, _or_ (ref->type &
BPF_REG_TRUSTED_MODIFIERS) (and no unsafe modifiers allowed), KF_RELEASE
only allows for ref_obj_id > 0.  Because KF_RELEASE today doesn't
automatically imply KF_TRUSTED_ARGS, some of these requirements are
enforced in different ways that can make the behavior of the verifier
feel unpredictable. For example, a KF_RELEASE kfunc with a NULL-able
argument will currently fail in the verifier with a message like, "arg#0
is ptr_or_null_ expected ptr_ or socket" rather than "Possibly NULL
pointer passed to trusted arg0". Our intention is the same, but the
semantics are different due to implemenetation details that kfunc authors
and BPF program writers should not need to care about.

Let's make the behavior of the verifier more consistent and intuitive by
having KF_RELEASE kfuncs imply the presence of KF_TRUSTED_ARGS. Our
eventual goal is to have all kfuncs assume KF_TRUSTED_ARGS by default
anyways, so this takes us a step in that direction.

Note that it does not make sense to assume KF_TRUSTED_ARGS for all
KF_ACQUIRE kfuncs. KF_ACQUIRE kfuncs can have looser semantics than
KF_RELEASE, with e.g. KF_RCU | KF_RET_NULL. We may want to have
KF_ACQUIRE imply KF_TRUSTED_ARGS _unless_ KF_RCU is specified, but that
can be left to another patch set, and there are no such subtleties to
address for KF_RELEASE.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230325213144.486885-4-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 16:56:22 -07:00
Sreevani Sreejith
08ff1c9f3e bpf, docs: Libbpf overview documentation
This patch documents overview of libbpf, including its features for
developing BPF programs.

Signed-off-by: Sreevani Sreejith <ssreevani@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20230315195405.2051559-1-ssreevani@meta.com
2023-03-18 10:17:39 -07:00
Bagas Sanjaya
0f10f647f4 bpf, docs: Use internal linking for link to netdev subsystem doc
Commit d56b0c461d ("bpf, docs: Fix link to netdev-FAQ target")
attempts to fix linking problem to undefined "netdev-FAQ" label
introduced in 287f4fa99a ("docs: Update references to netdev-FAQ")
by changing internal cross reference to netdev subsystem documentation
(Documentation/process/maintainer-netdev.rst) to external one at
docs.kernel.org. However, the linking problem is still not
resolved, as the generated link points to non-existent netdev-FAQ
section of the external doc, which when clicked, will instead going
to the top of the doc.

Revert back to internal linking by simply mention the doc path while
massaging the leading text to the link, since the netdev subsystem
doc contains no FAQs but rather general information about the subsystem.

Fixes: d56b0c461d ("bpf, docs: Fix link to netdev-FAQ target")
Fixes: 287f4fa99a ("docs: Update references to netdev-FAQ")
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230314074449.23620-1-bagasdotme@gmail.com
2023-03-17 13:58:57 +01:00
David Vernet
fec2c6d14f bpf,docs: Remove bpf_cpumask_kptr_get() from documentation
Now that the kfunc no longer exists, we can remove it and instead
describe how RCU can be used to get a struct bpf_cpumask from a map
value. This patch updates the BPF documentation accordingly.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230316054028.88924-6-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-16 12:28:30 -07:00
Dave Thaler
b9fe8e8d03 bpf, docs: Add signed comparison example
Improve clarity by adding an example of a signed comparison instruction

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Acked-by: David Vernet <void@manifault.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/20230310233814.4641-1-dthaler1968@googlemail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-13 22:10:45 -07:00
Dave Thaler
c1f9e14e3b bpf, docs: Explain helper functions
Add brief text about existence of helper functions, with details to go in
separate psABI text.

Note that text about runtime functions (kfuncs) is part of a separate patch,
not this one.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Link: https://lore.kernel.org/r/20230308205303.1308-1-dthaler1968@googlemail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-10 13:02:00 -08:00
Jakub Kicinski
d0ddf5065f Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Documentation/bpf/bpf_devel_QA.rst
  b7abcd9c65 ("bpf, doc: Link to submitting-patches.rst for general patch submission info")
  d56b0c461d ("bpf, docs: Fix link to netdev-FAQ target")
https://lore.kernel.org/all/20230307095812.236eb1be@canb.auug.org.au/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-09 22:22:11 -08:00
Bagas Sanjaya
b7abcd9c65 bpf, doc: Link to submitting-patches.rst for general patch submission info
The link for patch submission information in general refers to index
page for "Working with the kernel development community" section of
kernel docs, whereas the link should have been
Documentation/process/submitting-patches.rst instead.

Fix it by replacing the index target with the appropriate doc.

Fixes: 5422283848 ("bpf, doc: convert bpf_devel_QA.rst to use RST formatting")
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230228074523.11493-3-bagasdotme@gmail.com
2023-03-06 16:44:39 +01:00
Bagas Sanjaya
32db18d606 bpf, doc: Do not link to docs.kernel.org for kselftest link
The question on how to run BPF selftests have a reference link to kernel
selftest documentation (Documentation/dev-tools/kselftest.rst). However,
it uses external link to the documentation at kernel.org/docs (aka
docs.kernel.org) instead, which requires Internet access.

Fix this and replace the link with internal linking, by using :doc: directive
while keeping the anchor text.

Fixes: b7a27c3aaf ("bpf, doc: howto use/run the BPF selftests")
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230228074523.11493-2-bagasdotme@gmail.com
2023-03-06 16:44:34 +01:00
Alexei Starovoitov
20c09d92fa bpf: Introduce kptr_rcu.
The life time of certain kernel structures like 'struct cgroup' is protected by RCU.
Hence it's safe to dereference them directly from __kptr tagged pointers in bpf maps.
The resulting pointer is MEM_RCU and can be passed to kfuncs that expect KF_RCU.
Derefrence of other kptr-s returns PTR_UNTRUSTED.

For example:
struct map_value {
   struct cgroup __kptr *cgrp;
};

SEC("tp_btf/cgroup_mkdir")
int BPF_PROG(test_cgrp_get_ancestors, struct cgroup *cgrp_arg, const char *path)
{
  struct cgroup *cg, *cg2;

  cg = bpf_cgroup_acquire(cgrp_arg); // cg is PTR_TRUSTED and ref_obj_id > 0
  bpf_kptr_xchg(&v->cgrp, cg);

  cg2 = v->cgrp; // This is new feature introduced by this patch.
  // cg2 is PTR_MAYBE_NULL | MEM_RCU.
  // When cg2 != NULL, it's a valid cgroup, but its percpu_ref could be zero

  if (cg2)
    bpf_cgroup_ancestor(cg2, level); // safe to do.
}

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20230303041446.3630-4-alexei.starovoitov@gmail.com
2023-03-03 17:42:20 +01:00
Alexei Starovoitov
03b77e17ae bpf: Rename __kptr_ref -> __kptr and __kptr -> __kptr_untrusted.
__kptr meant to store PTR_UNTRUSTED kernel pointers inside bpf maps.
The concept felt useful, but didn't get much traction,
since bpf_rdonly_cast() was added soon after and bpf programs received
a simpler way to access PTR_UNTRUSTED kernel pointers
without going through restrictive __kptr usage.

Rename __kptr_ref -> __kptr and __kptr -> __kptr_untrusted to indicate
its intended usage.
The main goal of __kptr_untrusted was to read/write such pointers
directly while bpf_kptr_xchg was a mechanism to access refcnted
kernel pointers. The next patch will allow RCU protected __kptr access
with direct read. At that point __kptr_untrusted will be deprecated.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20230303041446.3630-2-alexei.starovoitov@gmail.com
2023-03-03 17:42:20 +01:00
David Vernet
cacad346f6 bpf, docs: Fix final bpf docs build failure
maps.rst in the BPF documentation links to the
/userspace-api/ebpf/syscall document
(Documentation/userspace-api/ebpf/syscall.rst). For some reason, if you
try to reference the document with :doc:, the docs build emits the
following warning:

./Documentation/bpf/maps.rst:13: WARNING: \
    unknown document: '/userspace-api/ebpf/syscall'

It appears that other places in the docs tree also don't support using
:doc:. Elsewhere in the BPF documentation, we just reference the kernel
docs page directly. Let's do that here to clean up the last remaining
noise in the docs build.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230302183918.54190-2-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-02 22:36:10 -08:00
David Vernet
d56b0c461d bpf, docs: Fix link to netdev-FAQ target
The BPF devel Q&A documentation page makes frequent reference to the
netdev-QA page via the netdev-FAQ rst link. This link is currently
broken, as is evidenced by the build output when making BPF docs:

./Documentation/bpf/bpf_devel_QA.rst:150: WARNING: undefined label: 'netdev-faq'
./Documentation/bpf/bpf_devel_QA.rst:206: WARNING: undefined label: 'netdev-faq'
./Documentation/bpf/bpf_devel_QA.rst:231: WARNING: undefined label: 'netdev-faq'
./Documentation/bpf/bpf_devel_QA.rst:396: WARNING: undefined label: 'netdev-faq'
./Documentation/bpf/bpf_devel_QA.rst:412: WARNING: undefined label: 'netdev-faq'

Fix the links to point to the actual netdev-faq page.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230302183918.54190-1-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-02 22:36:10 -08:00
David Vernet
db52b587c6 bpf, docs: Fix __uninit kfunc doc section
In commit d96d937d7c ("bpf: Add __uninit kfunc annotation"), the
__uninit kfunc annotation was documented in kfuncs.rst. You have to
fully underline a section in rst, or the build will issue a warning that
the title underline is too short:

./Documentation/bpf/kfuncs.rst:104: WARNING: Title underline too short.

2.2.2 __uninit Annotation
--------------------

This patch fixes that title underline.

Fixes: d96d937d7c ("bpf: Add __uninit kfunc annotation")
Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230301194910.602738-2-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-01 16:00:10 -08:00
Joanne Koong
d96d937d7c bpf: Add __uninit kfunc annotation
This patch adds __uninit as a kfunc annotation.

This will be useful for scenarios such as for example in dynptrs,
indicating whether the dynptr should be checked by the verifier as an
initialized or an uninitialized dynptr.

Without this annotation, the alternative would be needing to hard-code
in the verifier the specific kfunc to indicate that arg should be
treated as an uninitialized arg.

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Link: https://lore.kernel.org/r/20230301154953.641654-7-joannelkoong@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-01 09:55:24 -08:00
Jose E. Marchesi
ae256f9547 bpf, docs: Document BPF insn encoding in term of stored bytes
[Changes from V4:
- s/regs:16/regs:8 in figure.]

[Changes from V3:
- Back to src_reg and dst_reg, since they denote register numbers
  as opposed to the values stored in these registers.]

[Changes from V2:
- Use src and dst consistently in the document.
- Use a more graphical depiction of the 128-bit instruction.
- Remove `Where:' fragment.
- Clarify that unused bits are reserved and shall be zeroed.]

[Changes from V1:
- Use rst literal blocks for figures.
- Avoid using | in the basic instruction/pseudo instruction figure.
- Rebased to today's bpf-next master branch.]

This patch modifies instruction-set.rst so it documents the encoding
of BPF instructions in terms of how the bytes are stored (be it in an
ELF file or as bytes in a memory buffer to be loaded into the kernel
or some other BPF consumer) as opposed to how the instruction looks
like once loaded.

This is hopefully easier to understand by implementors looking to
generate and/or consume bytes conforming BPF instructions.

The patch also clarifies that the unused bytes in a pseudo-instruction
shall be cleared with zeros.

Signed-off-by: Jose E. Marchesi <jose.marchesi@oracle.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/87h6v6i0da.fsf_-_@oracle.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-28 09:55:18 -08:00
Bagas Sanjaya
a07484c083 bpf, docs: Fix link to BTF doc
Ross reported broken link to BTF documentation
(Documentation/bpf/btf.rst) in Documentation/bpf/bpf_devel_QA.rst. The
link in question is written using external link syntax, with the target
refers to BTF doc in reST source (btf.rst), which doesn't exist in
resulting HTML output.

Fix the link by replacing external link syntax with simply writing out
the target doc, which the link will be generated to the correct HTML doc
target.

Fixes: 6736aa793c ("selftests/bpf: Add general instructions for test execution")
Reported-by: Ross Zwisler <zwisler@google.com>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Ross Zwisler <zwisler@google.com>
Link: https://lore.kernel.org/linux-doc/Y++09LKx25dtR4Ow@google.com/
Link: https://lore.kernel.org/bpf/20230222083530.26136-1-bagasdotme@gmail.com
2023-02-27 21:54:14 +01:00
Tejun Heo
332ea1f697 bpf: Add bpf_cgroup_from_id() kfunc
cgroup ID is an userspace-visible 64bit value uniquely identifying a given
cgroup. As the IDs are used widely, it's useful to be able to look up the
matching cgroups. Add bpf_cgroup_from_id().

v2: Separate out selftest into its own patch as suggested by Alexei.

Signed-off-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/Y/bBaG96t0/gQl9/@slm.duckdns.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-23 08:33:05 -08:00
Dave Thaler
746ce76712 bpf, docs: Add explanation of endianness
Document the discussion from the email thread on the IETF bpf list,
where it was explained that the raw format varies by endianness
of the processor.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230220223742.1347-1-dthaler1968@googlemail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-22 14:04:55 -08:00
Bagas Sanjaya
e2d323a1f0 Documentation: bpf: Add missing line break separator in node_data struct code block
Stephen Rothwell reported htmldocs warning when merging bpf-next tree,
which was the same warning as reported by kernel test robot:

Documentation/bpf/graph_ds_impl.rst:62: ERROR: Error in "code-block" directive:
maximum 1 argument(s) allowed, 12 supplied.

The error is due to Sphinx confuses node_data struct declaration with
code-block directive option.

Fix the warning by separating the code-block marker with node_data struct
declaration.

Link: https://lore.kernel.org/linux-next/20230215144505.4751d823@canb.auug.org.au/
Link: https://lore.kernel.org/linux-doc/202302151123.wUE5FYFx-lkp@intel.com/
Fixes: c31315c3aa ("bpf, documentation: Add graph documentation for non-owning refs")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Link: https://lore.kernel.org/r/20230215123253.41552-3-bagasdotme@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-15 08:43:51 -08:00
Dave Marchevsky
c31315c3aa bpf, documentation: Add graph documentation for non-owning refs
It is difficult to intuit the semantics of owning and non-owning
references from verifier code. In order to keep the high-level details
from being lost in the mailing list, this patch adds documentation
explaining semantics and details.

The target audience of doc added in this patch is folks working on BPF
internals, as there's focus on "what should the verifier do here". Via
reorganization or copy-and-paste, much of the content can probably be
repurposed for BPF program writer audience as well.

Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/r/20230214004017.2534011-9-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-13 19:40:53 -08:00
Dave Thaler
d00d5b82f0 bpf, docs: Add note about type convention
Add explanation about use of "u64", "u32", etc. as
the type convention used in BPF documentation.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230127014706.1005-1-dthaler1968@googlemail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-08 09:25:26 -08:00
Toke Høiland-Jørgensen
27b53b7364 bpf/docs: Update design QA to be consistent with kfunc lifecycle docs
Cong pointed out that there are some inconsistencies between the BPF design
QA and the lifecycle expectations documentation we added for kfuncs. Let's
update the QA file to be consistent with the kfunc docs, and add references
where it makes sense. Also document that modules may export kfuncs now.

v3:
- Grammar nit + ack from David

v2:
- Fix repeated word (s/defined defined/defined/)

Reported-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20230208164143.286392-1-toke@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-08 09:24:16 -08:00
Dave Thaler
a92adde8d3 bpf, docs: Use consistent names for the same field
Use consistent names for the same field, e.g., 'dst' vs 'dst_reg'.
Previously a mix of terms were used for the same thing in various cases.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230127224555.916-1-dthaler1968@googlemail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-07 18:45:43 -08:00
David Vernet
16c294a6aa bpf/docs: Document kfunc lifecycle / stability expectations
BPF kernel <-> kernel API stability has been discussed at length over
the last several weeks and months. Now that we've largely aligned over
kfuncs being the way forward, and BPF helpers being considered
functionally frozen, it's time to document the expectations for kfunc
lifecycles and stability so that everyone (BPF users, kfunc developers,
and maintainers) are all aligned, and have a crystal-clear understanding
of the expectations surrounding kfuncs.

To do that, this patch adds that documentation to the main kfuncs
documentation page via a new 'kfunc lifecycle expectations' section. The
patch describes how decisions are made in the kernel regarding whether
to include, keep, deprecate, or change / remove a kfunc. As described
very overtly in the patch itself, but likely worth highlighting here:

"kfunc stability" does not mean, nor ever will mean, "BPF APIs may block
development elsewhere in the kernel".

Rather, the intention and expectation is for kfuncs to be treated like
EXPORT_SYMBOL_GPL symbols in the kernel. The goal is for kfuncs to be a
safe and valuable option for maintainers and kfunc developers to extend
the kernel, without tying anyone's hands, or imposing any kind of
restrictions on maintainers in the same way that UAPI changes do.

In addition to the 'kfunc lifecycle expectations' section, this patch
also adds documentation for a new KF_DEPRECATED kfunc flag which kfunc
authors or maintainers can choose to add to kfuncs if and when they
decide to deprecate them. Note that as described in the patch itself, a
kfunc need not be deprecated before being changed or removed -- this
flag is simply provided as an available deprecation mechanism for those
that want to provide a deprecation story / timeline to their users.
When necessary, kfuncs may be changed or removed to accommodate changes
elsewhere in the kernel without any deprecation at all.

Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Co-developed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230203155727.793518-2-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-03 09:01:29 -08:00
Eduard Zingerman
cb6018485c docs/bpf: Add description of register liveness tracking algorithm
This is a followup for [1], adds an overview for the register liveness
tracking, covers the following points:
- why register liveness tracking is useful;
- how register parentage chains are constructed;
- how liveness marks are applied using the parentage chains.

[1] https://lore.kernel.org/bpf/CAADnVQKs2i1iuZ5SUGuJtxWVfGYR9kDgYKhq3rNV+kBLQCu7rA@mail.gmail.com/

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Reviewed-by: Edward Cree <ecree.xilinx@gmail.com>
Link: https://lore.kernel.org/r/20230202125713.821931-2-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-02 20:21:59 -08:00
David Vernet
98e6ab7a04 bpf: Document usage of the new __bpf_kfunc macro
Now that the __bpf_kfunc macro has been added to linux/btf.h, include a
blurb about it in the kfuncs.rst file. In order for the macro to
successfully render with .. kernel-doc, we'll also need to add it to the
c_id_attributes array.

Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20230201173016.342758-3-void@manifault.com
2023-02-02 00:25:14 +01:00
Randy Dunlap
1d3cab43f4 Documentation: bpf: correct spelling
Correct spelling problems for Documentation/bpf/ as reported
by codespell.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: bpf@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Link: https://lore.kernel.org/r/20230128195046.13327-1-rdunlap@infradead.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-28 12:22:20 -08:00
David Vernet
027bdec893 bpf/docs: Document the nocast aliasing behavior of ___init
When comparing BTF IDs for pointers being passed to kfunc arguments, the
verifier will allow pointer types that are equivalent according to the C
standard. For example, for:

struct bpf_cpumask {
	cpumask_t cpumask;
	refcount_t usage;
};

The verifier will allow a struct bpf_cpumask * to be passed to a kfunc
that takes a const struct cpumask * (cpumask_t is a typedef of struct
cpumask). The exception to this rule is if a type is suffixed with
___init, such as:

struct nf_conn___init {
	struct nf_conn ct;
};

The verifier will _not_ allow a struct nf_conn___init * to be passed to
a kfunc that expects a struct nf_conn *. This patch documents this
behavior in the kfuncs documentation page.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230125143816.721952-8-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-25 07:57:50 -08:00
David Vernet
d94cbde218 bpf/docs: Document how nested trusted fields may be defined
A prior change defined a new BTF_TYPE_SAFE_NESTED macro in the verifier
which allows developers to specify when a pointee field in a struct type
should inherit its parent pointer's trusted status. This patch updates
the kfuncs documentation to specify this macro and how it can be used.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230125143816.721952-7-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-25 07:57:50 -08:00
David Vernet
bdbda39584 bpf/docs: Document cpumask kfuncs in a new file
Now that we've added a series of new cpumask kfuncs, we should document
them so users can easily use them. This patch adds a new cpumasks.rst
file to document them.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230125143816.721952-6-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-25 07:57:50 -08:00
Dave Thaler
0eb9d19e22 bpf, docs: Fix modulo zero, division by zero, overflow, and underflow
Fix modulo zero, division by zero, overflow, and underflow. Also clarify how
a negative immediate value is used in unsigned division.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230124001218.827-1-dthaler1968@googlemail.com
2023-01-24 16:46:40 +01:00
Jakub Kicinski
d75858ef10 bpf-next-for-netdev
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
bpf-next 2023-01-04

We've added 45 non-merge commits during the last 21 day(s) which contain
a total of 50 files changed, 1454 insertions(+), 375 deletions(-).

The main changes are:

1) Fixes, improvements and refactoring of parts of BPF verifier's
   state equivalence checks, from Andrii Nakryiko.

2) Fix a few corner cases in libbpf's BTF-to-C converter in particular
   around padding handling and enums, also from Andrii Nakryiko.

3) Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better
  support decap on GRE tunnel devices not operating in collect metadata,
  from Christian Ehrig.

4) Improve x86 JIT's codegen for PROBE_MEM runtime error checks,
   from Dave Marchevsky.

5) Remove the need for trace_printk_lock for bpf_trace_printk
   and bpf_trace_vprintk helpers, from Jiri Olsa.

6) Add proper documentation for BPF_MAP_TYPE_SOCK{MAP,HASH} maps,
   from Maryam Tahhan.

7) Improvements in libbpf's btf_parse_elf error handling, from Changbin Du.

8) Bigger batch of improvements to BPF tracing code samples,
   from Daniel T. Lee.

9) Add LoongArch support to libbpf's bpf_tracing helper header,
   from Hengqi Chen.

10) Fix a libbpf compiler warning in perf_event_open_probe on arm32,
    from Khem Raj.

11) Optimize bpf_local_storage_elem by removing 56 bytes of padding,
    from Martin KaFai Lau.

12) Use pkg-config to locate libelf for resolve_btfids build,
    from Shen Jiamin.

13) Various libbpf improvements around API documentation and errno
    handling, from Xin Liu.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (45 commits)
  libbpf: Return -ENODATA for missing btf section
  libbpf: Add LoongArch support to bpf_tracing.h
  libbpf: Restore errno after pr_warn.
  libbpf: Added the description of some API functions
  libbpf: Fix invalid return address register in s390
  samples/bpf: Use BPF_KSYSCALL macro in syscall tracing programs
  samples/bpf: Fix tracex2 by using BPF_KSYSCALL macro
  samples/bpf: Change _kern suffix to .bpf with syscall tracing program
  samples/bpf: Use vmlinux.h instead of implicit headers in syscall tracing program
  samples/bpf: Use kyscall instead of kprobe in syscall tracing program
  bpf: rename list_head -> graph_root in field info types
  libbpf: fix errno is overwritten after being closed.
  bpf: fix regs_exact() logic in regsafe() to remap IDs correctly
  bpf: perform byte-by-byte comparison only when necessary in regsafe()
  bpf: reject non-exact register type matches in regsafe()
  bpf: generalize MAYBE_NULL vs non-MAYBE_NULL rule
  bpf: reorganize struct bpf_reg_state fields
  bpf: teach refsafe() to take into account ID remapping
  bpf: Remove unused field initialization in bpf's ctl_table
  selftests/bpf: Add jit probe_mem corner case tests to s390x denylist
  ...
====================

Link: https://lore.kernel.org/r/20230105000926.31350-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-04 20:21:25 -08:00
Maryam Tahhan
cafb92d719 docs: BPF_MAP_TYPE_SOCK[MAP|HASH]
Add documentation for BPF_MAP_TYPE_SOCK[MAP|HASH]
including kernel versions introduced, usage
and examples.

Signed-off-by: Maryam Tahhan <mtahhan@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20221219095512.26534-1-mtahhan@redhat.com
2022-12-20 15:54:05 -08:00
Donald Hunter
d2b497a973 docs/bpf: Reword docs for BPF_MAP_TYPE_SK_STORAGE
Improve the grammar of the function descriptions and highlight
that the key is a socket fd.

Fixes: f3212ad5b7 ("docs/bpf: Add documentation for BPF_MAP_TYPE_SK_STORAGE")
Reported-by: Martin KaFai Lau <martin.lau@linux.dev>
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20221212101600.56026-1-donald.hunter@gmail.com
2022-12-14 18:35:41 +01:00
Donald Hunter
f3212ad5b7 docs/bpf: Add documentation for BPF_MAP_TYPE_SK_STORAGE
Add documentation for the BPF_MAP_TYPE_SK_STORAGE including
kernel version introduced, usage and examples.

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20221209112401.69319-1-donald.hunter@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-09 09:42:16 -08:00
David Vernet
36aa10ffd6 bpf/docs: Document struct cgroup * kfuncs
bpf_cgroup_acquire(), bpf_cgroup_release(), bpf_cgroup_kptr_get(), and
bpf_cgroup_ancestor(), are kfuncs that were recently added to
kernel/bpf/helpers.c. These are "core" kfuncs in that they're available
for use in any tracepoint or struct_ops BPF program. Though they have no
ABI stability guarantees, we should still document them. This patch adds
a struct cgroup * subsection to the Core kfuncs section which describes
each of these kfuncs.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20221207204911.873646-3-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 17:11:24 -08:00
David Vernet
25c5e92d19 bpf/docs: Document struct task_struct * kfuncs
bpf_task_acquire(), bpf_task_release(), and bpf_task_from_pid() are
kfuncs that were recently added to kernel/bpf/helpers.c. These are
"core" kfuncs in that they're available for use for any tracepoint or
struct_ops BPF program. Though they have no ABI stability guarantees, we
should still document them. This patch adds a new Core kfuncs section to
the BPF kfuncs doc, and adds entries for all of these task kfuncs.

Note that bpf_task_kptr_get() is not documented, as it still returns
NULL while we're working to resolve how it can use RCU to ensure struct
task_struct * lifetime.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20221207204911.873646-2-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 17:09:13 -08:00
Sreevani Sreejith
8972e18a43 bpf, docs: BPF Iterator Document
Document that describes how BPF iterators work, how to use iterators,
and how to pass parameters in BPF iterators.

Acked-by: David Vernet <void@manifault.com>
Signed-off-by: Sreevani Sreejith <psreep@gmail.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221202221710.320810-2-ssreevani@meta.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-04 16:41:22 -08:00
Yonghong Song
f536256498 docs/bpf: Add KF_RCU documentation
Add proper KF_RCU documentation in kfuncs.rst.

Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221203184613.478967-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-04 12:52:40 -08:00
Zheng Yejian
bc067cacb6 bpf, docs: Correct the example of BPF_XOR
Refer to description of BPF_XOR, dst_reg should be used but not src_reg
in the examples.

Fixes: be3193cded ("bpf, docs: Add subsections for ALU and JMP instructions")
Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221129134558.2757043-1-zhengyejian1@huawei.com
2022-12-02 21:27:32 +01:00
Maryam Tahhan
2b3e8f6f5b docs/bpf: Add BPF_MAP_TYPE_XSKMAP documentation
Add documentation for BPF_MAP_TYPE_XSKMAP including kernel version introduced,
usage and examples.

Signed-off-by: Maryam Tahhan <mtahhan@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221123090043.83945-1-mtahhan@redhat.com
2022-11-25 00:33:14 +01:00
Rong Tao
b74344cbed docs/bpf: Update btf selftests program and add link
Commit c64779e24e88("selftests/bpf: Merge most of test_btf into test_progs")
renamed the BTF selftest from 'test_btf.c' to 'prog_tests/btf.c'.

Signed-off-by: Rong Tao <rongtao@cestc.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/tencent_1FA6904156E8E599CAE4ABDBE80F22830106@qq.com
2022-11-25 00:00:15 +01:00
Donald Hunter
539886a32a docs/bpf: Fix sphinx warnings in BPF map docs
Fix duplicate C declaration warnings when using sphinx >= 3.1.

Reported-by: Akira Yokosawa <akiyks@gmail.com>
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Akira Yokosawa <akiyks@gmail.com>
Link: https://lore.kernel.org/bpf/ed4dac84-1b12-5c58-e4de-93ab9ac67c09@gmail.com
Link: https://lore.kernel.org/bpf/20221122143933.91321-1-donald.hunter@gmail.com
2022-11-24 01:05:04 +01:00
Donald Hunter
264c21867a docs/bpf: Document BPF_MAP_TYPE_BLOOM_FILTER
Add documentation for BPF_MAP_TYPE_BLOOM_FILTER including kernel
BPF helper usage, userspace usage and examples.

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Joanne Koong <joannelkoong@gmail.com>
Link: https://lore.kernel.org/bpf/20221123141151.54556-1-donald.hunter@gmail.com
2022-11-23 22:47:32 +01:00
Maryam Tahhan
c645eee4d3 docs/bpf: Fix sphinx warnings for devmap
Sphinx version >=3.1 warns about duplicate function declarations in the
DEVMAP documentation. This is because the function name is the same for
kernel and user space BPF progs but the parameters and return types
they take is what differs. This patch moves from using the ``c:function::``
directive to using the ``code-block:: c`` directive. The patches also fix
the indentation for the text associated with the "new" code block delcarations.
The missing support of c:namespace-push:: and c:namespace-pop:: directives by
helper scripts for kernel documentation prevents using the ``c:function::``
directive with proper namespacing.

Signed-off-by: Maryam Tahhan <mtahhan@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221123092321.88558-3-mtahhan@redhat.com
2022-11-23 22:40:27 +01:00
Maryam Tahhan
3685b0dc0d docs/bpf: Fix sphinx warnings for cpumap
Sphinx version >=3.1 warns about duplicate function declarations in the
CPUMAP documentation. This is because the function name is the same for
kernel and user space BPF progs but the parameters and return types
they take is what differs. This patch moves from using the ``c:function::``
directive to using the ``code-block:: c`` directive. The patches also fix
the indentation for the text associated with the "new" code block delcarations.
The missing support of c:namespace-push:: and c:namespace-pop:: directives by
helper scripts for kernel documentation prevents using the ``c:function::``
directive with proper namespacing.

Signed-off-by: Maryam Tahhan <mtahhan@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221123092321.88558-2-mtahhan@redhat.com
2022-11-23 22:38:53 +01:00
Donald Hunter
c742cb7c3e docs/bpf: Add table of BPF program types to libbpf docs
Extend the libbpf documentation with a table of program types,
attach points and ELF section names.

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20221121121734.98329-1-donald.hunter@gmail.com
2022-11-23 13:31:20 -08:00
David Vernet
3f00c52393 bpf: Allow trusted pointers to be passed to KF_TRUSTED_ARGS kfuncs
Kfuncs currently support specifying the KF_TRUSTED_ARGS flag to signal
to the verifier that it should enforce that a BPF program passes it a
"safe", trusted pointer. Currently, "safe" means that the pointer is
either PTR_TO_CTX, or is refcounted. There may be cases, however, where
the kernel passes a BPF program a safe / trusted pointer to an object
that the BPF program wishes to use as a kptr, but because the object
does not yet have a ref_obj_id from the perspective of the verifier, the
program would be unable to pass it to a KF_ACQUIRE | KF_TRUSTED_ARGS
kfunc.

The solution is to expand the set of pointers that are considered
trusted according to KF_TRUSTED_ARGS, so that programs can invoke kfuncs
with these pointers without getting rejected by the verifier.

There is already a PTR_UNTRUSTED flag that is set in some scenarios,
such as when a BPF program reads a kptr directly from a map
without performing a bpf_kptr_xchg() call. These pointers of course can
and should be rejected by the verifier. Unfortunately, however,
PTR_UNTRUSTED does not cover all the cases for safety that need to
be addressed to adequately protect kfuncs. Specifically, pointers
obtained by a BPF program "walking" a struct are _not_ considered
PTR_UNTRUSTED according to BPF. For example, say that we were to add a
kfunc called bpf_task_acquire(), with KF_ACQUIRE | KF_TRUSTED_ARGS, to
acquire a struct task_struct *. If we only used PTR_UNTRUSTED to signal
that a task was unsafe to pass to a kfunc, the verifier would mistakenly
allow the following unsafe BPF program to be loaded:

SEC("tp_btf/task_newtask")
int BPF_PROG(unsafe_acquire_task,
             struct task_struct *task,
             u64 clone_flags)
{
        struct task_struct *acquired, *nested;

        nested = task->last_wakee;

        /* Would not be rejected by the verifier. */
        acquired = bpf_task_acquire(nested);
        if (!acquired)
                return 0;

        bpf_task_release(acquired);
        return 0;
}

To address this, this patch defines a new type flag called PTR_TRUSTED
which tracks whether a PTR_TO_BTF_ID pointer is safe to pass to a
KF_TRUSTED_ARGS kfunc or a BPF helper function. PTR_TRUSTED pointers are
passed directly from the kernel as a tracepoint or struct_ops callback
argument. Any nested pointer that is obtained from walking a PTR_TRUSTED
pointer is no longer PTR_TRUSTED. From the example above, the struct
task_struct *task argument is PTR_TRUSTED, but the 'nested' pointer
obtained from 'task->last_wakee' is not PTR_TRUSTED.

A subsequent patch will add kfuncs for storing a task kfunc as a kptr,
and then another patch will add selftests to validate.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20221120051004.3605026-3-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-20 09:16:21 -08:00
Maryam Tahhan
d1e91173cd bpf, docs: DEVMAPs and XDP_REDIRECT
Add documentation for BPF_MAP_TYPE_DEVMAP and BPF_MAP_TYPE_DEVMAP_HASH
including kernel version introduced, usage and examples.

Add documentation that describes XDP_REDIRECT.

Signed-off-by: Maryam Tahhan <mtahhan@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20221115144921.165483-1-mtahhan@redhat.com
2022-11-18 23:16:31 +01:00
Kumar Kartikeya Dwivedi
a50388dbb3 bpf: Support constant scalar arguments for kfuncs
Allow passing known constant scalars as arguments to kfuncs that do not
represent a size parameter. We use mark_chain_precision for the constant
scalar argument to mark it precise. This makes the search pruning
optimization of verifier more conservative for such kfunc calls, and
each non-distinct argument is considered unequivalent.

We will use this support to then expose a bpf_obj_new function where it
takes the local type ID of a type in program BTF, and returns a
PTR_TO_BTF_ID | MEM_ALLOC to the local type, and allows programs to
allocate their own objects.

Each type ID resolves to a distinct type with a possibly distinct size,
hence the type ID constant matters in terms of program safety and its
precision needs to be checked between old and cur states inside regsafe.
The use of mark_chain_precision enables this.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20221118015614.2013203-13-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-17 19:22:13 -08:00
Daniel Müller
383f1a8df8 bpf/docs: Include blank lines between bullet points in bpf_devel_QA.rst
Commit 26a9b433cf ("bpf/docs: Document how to run CI without patch
submission") caused a warning to be generated when compiling the
documentation:

 > bpf_devel_QA.rst:55: WARNING: Unexpected indentation.
 > bpf_devel_QA.rst:56: WARNING: Block quote ends without a blank line

This change fixes the problem by inserting the required blank lines.

Fixes: 26a9b433cf ("bpf/docs: Document how to run CI without patch submission")
Reported-by: Akira Yokosawa <akiyks@gmail.com>
Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Akira Yokosawa <akiyks@gmail.com>
Link: https://lore.kernel.org/bpf/20221116174358.2744613-1-deso@posteo.net
2022-11-17 16:26:42 +01:00
Donald Hunter
e0eb60829a docs/bpf: Fix sample code in MAP_TYPE_ARRAY docs
Remove mistaken & from code example in MAP_TYPE_ARRAY docs

Fixes: 1cfa97b30c ("bpf, docs: Document BPF_MAP_TYPE_ARRAY")
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20221115095910.86407-1-donald.hunter@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-15 21:33:47 -08:00
Daniel Müller
26a9b433cf bpf/docs: Document how to run CI without patch submission
This change documents the process for running the BPF CI before
submitting a patch to the upstream mailing list, similar to what happens
if a patch is send to bpf@vger.kernel.org: it builds kernel and
selftests and runs the latter on different architecture (but it notably
does not cover stylistic checks such as cover letter verification).

Running BPF CI this way can help achieve better test coverage ahead of
patch submission than merely running locally (say, using
tools/testing/selftests/bpf/vmtest.sh), as additional architectures may
be covered as well.

Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221114211501.2068684-1-deso@posteo.net
2022-11-15 15:33:27 +01:00
Kumar Kartikeya Dwivedi
1f6d52f1a8 bpf: Remove local kptr references in documentation
We don't want to commit to a specific name for these. Simply call them
allocated objects coming from bpf_obj_new, which is completely clear in
itself.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20221114191547.1694267-2-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-14 21:52:45 -08:00
Maryam Tahhan
e662c77536 bpf, docs: Fixup cpumap sphinx >= 3.1 warning
Fixup bpf_map_update_elem() declaration to use a single line.

Reported-by: Akira Yokosawa <akiyks@gmail.com>
Signed-off-by: Maryam Tahhan <mtahhan@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Akira Yokosawa <akiyks@gmail.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221113103327.3287482-1-mtahhan@redhat.com
2022-11-14 19:10:57 +01:00
Dave Tucker
1cfa97b30c bpf, docs: Document BPF_MAP_TYPE_ARRAY
Add documentation for the BPF_MAP_TYPE_ARRAY including kernel version
introduced, usage and examples. Also document BPF_MAP_TYPE_PERCPU_ARRAY
which is similar.

Co-developed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Dave Tucker <dave@dtucker.co.uk>
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Maryam Tahhan <mtahhan@redhat.com>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Link: https://lore.kernel.org/bpf/20221109174604.31673-2-donald.hunter@gmail.com
2022-11-11 11:37:59 -08:00
Donald Hunter
64488ca57a docs/bpf: Document BPF map types QUEUE and STACK
Add documentation for BPF_MAP_TYPE_QUEUE and BPF_MAP_TYPE_STACK,
including usage and examples.

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20221108093314.44851-1-donald.hunter@gmail.com
2022-11-11 11:34:39 -08:00
Donald Hunter
f720b84811 docs/bpf: Document BPF ARRAY_OF_MAPS and HASH_OF_MAPS
Add documentation for the ARRAY_OF_MAPS and HASH_OF_MAPS map types,
including usage and examples.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20221108102215.47297-1-donald.hunter@gmail.com
2022-11-11 11:32:54 -08:00
Maryam Tahhan
161939abc8 docs/bpf: Document BPF_MAP_TYPE_CPUMAP map
Add documentation for BPF_MAP_TYPE_CPUMAP including
kernel version introduced, usage and examples.

Co-developed-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Maryam Tahhan <mtahhan@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20221107165207.2682075-2-mtahhan@redhat.com
2022-11-11 11:32:54 -08:00
Donald Hunter
83177c0dca docs/bpf: Document BPF_MAP_TYPE_LPM_TRIE map
Add documentation for BPF_MAP_TYPE_LPM_TRIE including kernel
BPF helper usage, userspace usage and examples.

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221101114542.24481-2-donald.hunter@gmail.com
2022-11-11 11:32:49 -08:00
Bagas Sanjaya
25906092ed Documentation: bpf: Escape underscore in BPF type name prefix
Sphinx reported unknown target warning:

Documentation/bpf/bpf_design_QA.rst:329: WARNING: Unknown target name: "bpf".

The warning is caused by BPF type name prefix ("bpf_") which is written
without escaping the trailing underscore.

Escape the underscore to fix the warning. While at it, wrap the
containing paragraph in less than 80 characters.

Fixes: 9805af8d8a ("bpf: Document UAPI details for special BPF types")
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: KP Singh <kpsingh@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20221104123913.50610-1-bagasdotme@gmail.com
2022-11-04 16:10:07 -07:00
Kumar Kartikeya Dwivedi
9805af8d8a bpf: Document UAPI details for special BPF types
The kernel recognizes some special BPF types in map values or local
kptrs. Document that only bpf_spin_lock and bpf_timer will preserve
backwards compatibility, and kptr will preserve backwards compatibility
for the operations on the pointer, not the types supported for such
kptrs.

For local kptrs, document that there are no stability guarantees at all.

Finally, document that 'bpf_' namespace is reserved for adding future
special fields, hence BPF programs must not declare types with such
names in their programs and still expect backwards compatibility.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20221103191013.1236066-2-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-03 19:31:13 -07:00
Yonghong Song
d43198017e docs/bpf: Add documentation for new cgroup local storage
Add some descriptions and examples for BPF_MAP_TYPE_CGRP_STORAGE.
Also illustate the major difference between BPF_MAP_TYPE_CGRP_STORAGE
and BPF_MAP_TYPE_CGROUP_STORAGE and recommend to use
BPF_MAP_TYPE_CGRP_STORAGE instead of BPF_MAP_TYPE_CGROUP_STORAGE
in the end.

Acked-by: David Vernet <void@manifault.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221026042922.676383-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-10-25 23:19:20 -07:00
Donald Hunter
fb73a20ebe bpf, docs: Reformat BPF maps page to be more readable
Add a more complete introduction, with links to man pages.
Move toctree of map types above usage notes.
Format usage notes to improve readability.

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20221012152715.25073-1-donald.hunter@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-10-20 18:53:34 -07:00
Linus Torvalds
0326074ff4 Networking changes for 6.1.
Core
 ----
 
  - Introduce and use a single page frag cache for allocating small skb
    heads, clawing back the 10-20% performance regression in UDP flood
    test from previous fixes.
 
  - Run packets which already went thru HW coalescing thru SW GRO.
    This significantly improves TCP segment coalescing and simplifies
    deployments as different workloads benefit from HW or SW GRO.
 
  - Shrink the size of the base zero-copy send structure.
 
  - Move TCP init under a new slow / sleepable version of DO_ONCE().
 
 BPF
 ---
 
  - Add BPF-specific, any-context-safe memory allocator.
 
  - Add helpers/kfuncs for PKCS#7 signature verification from BPF
    programs.
 
  - Define a new map type and related helpers for user space -> kernel
    communication over a ring buffer (BPF_MAP_TYPE_USER_RINGBUF).
 
  - Allow targeting BPF iterators to loop through resources of one
    task/thread.
 
  - Add ability to call selected destructive functions.
    Expose crash_kexec() to allow BPF to trigger a kernel dump.
    Use CAP_SYS_BOOT check on the loading process to judge permissions.
 
  - Enable BPF to collect custom hierarchical cgroup stats efficiently
    by integrating with the rstat framework.
 
  - Support struct arguments for trampoline based programs.
    Only structs with size <= 16B and x86 are supported.
 
  - Invoke cgroup/connect{4,6} programs for unprivileged ICMP ping
    sockets (instead of just TCP and UDP sockets).
 
  - Add a helper for accessing CLOCK_TAI for time sensitive network
    related programs.
 
  - Support accessing network tunnel metadata's flags.
 
  - Make TCP SYN ACK RTO tunable by BPF programs with TCP Fast Open.
 
  - Add support for writing to Netfilter's nf_conn:mark.
 
 Protocols
 ---------
 
  - WiFi: more Extremely High Throughput (EHT) and Multi-Link
    Operation (MLO) work (802.11be, WiFi 7).
 
  - vsock: improve support for SO_RCVLOWAT.
 
  - SMC: support SO_REUSEPORT.
 
  - Netlink: define and document how to use netlink in a "modern" way.
    Support reporting missing attributes via extended ACK.
 
  - IPSec: support collect metadata mode for xfrm interfaces.
 
  - TCPv6: send consistent autoflowlabel in SYN_RECV state
    and RST packets.
 
  - TCP: introduce optional per-netns connection hash table to allow
    better isolation between namespaces (opt-in, at the cost of memory
    and cache pressure).
 
  - MPTCP: support TCP_FASTOPEN_CONNECT.
 
  - Add NEXT-C-SID support in Segment Routing (SRv6) End behavior.
 
  - Adjust IP_UNICAST_IF sockopt behavior for connected UDP sockets.
 
  - Open vSwitch:
    - Allow specifying ifindex of new interfaces.
    - Allow conntrack and metering in non-initial user namespace.
 
  - TLS: support the Korean ARIA-GCM crypto algorithm.
 
  - Remove DECnet support.
 
 Driver API
 ----------
 
  - Allow selecting the conduit interface used by each port
    in DSA switches, at runtime.
 
  - Ethernet Power Sourcing Equipment and Power Device support.
 
  - Add tc-taprio support for queueMaxSDU parameter, i.e. setting
    per traffic class max frame size for time-based packet schedules.
 
  - Support PHY rate matching - adapting between differing host-side
    and link-side speeds.
 
  - Introduce QUSGMII PHY mode and 1000BASE-KX interface mode.
 
  - Validate OF (device tree) nodes for DSA shared ports; make
    phylink-related properties mandatory on DSA and CPU ports.
    Enforcing more uniformity should allow transitioning to phylink.
 
  - Require that flash component name used during update matches one
    of the components for which version is reported by info_get().
 
  - Remove "weight" argument from driver-facing NAPI API as much
    as possible. It's one of those magic knobs which seemed like
    a good idea at the time but is too indirect to use in practice.
 
  - Support offload of TLS connections with 256 bit keys.
 
 New hardware / drivers
 ----------------------
 
  - Ethernet:
    - Microchip KSZ9896 6-port Gigabit Ethernet Switch
    - Renesas Ethernet AVB (EtherAVB-IF) Gen4 SoCs
    - Analog Devices ADIN1110 and ADIN2111 industrial single pair
      Ethernet (10BASE-T1L) MAC+PHY.
    - Rockchip RV1126 Gigabit Ethernet (a version of stmmac IP).
 
  - Ethernet SFPs / modules:
    - RollBall / Hilink / Turris 10G copper SFPs
    - HALNy GPON module
 
  - WiFi:
    - CYW43439 SDIO chipset (brcmfmac)
    - CYW89459 PCIe chipset (brcmfmac)
    - BCM4378 on Apple platforms (brcmfmac)
 
 Drivers
 -------
 
  - CAN:
    - gs_usb: HW timestamp support
 
  - Ethernet PHYs:
    - lan8814: cable diagnostics
 
  - Ethernet NICs:
    - Intel (100G):
      - implement control of FCS/CRC stripping
      - port splitting via devlink
      - L2TPv3 filtering offload
    - nVidia/Mellanox:
      - tunnel offload for sub-functions
      - MACSec offload, w/ Extended packet number and replay
        window offload
      - significantly restructure, and optimize the AF_XDP support,
        align the behavior with other vendors
    - Huawei:
      - configuring DSCP map for traffic class selection
      - querying standard FEC statistics
      - querying SerDes lane number via ethtool
    - Marvell/Cavium:
      - egress priority flow control
      - MACSec offload
    - AMD/SolarFlare:
      - PTP over IPv6 and raw Ethernet
    - small / embedded:
      - ax88772: convert to phylink (to support SFP cages)
      - altera: tse: convert to phylink
      - ftgmac100: support fixed link
      - enetc: standard Ethtool counters
      - macb: ZynqMP SGMII dynamic configuration support
      - tsnep: support multi-queue and use page pool
      - lan743x: Rx IP & TCP checksum offload
      - igc: add xdp frags support to ndo_xdp_xmit
 
  - Ethernet high-speed switches:
    - Marvell (prestera):
      - support SPAN port features (traffic mirroring)
      - nexthop object offloading
    - Microchip (sparx5):
      - multicast forwarding offload
      - QoS queuing offload (tc-mqprio, tc-tbf, tc-ets)
 
  - Ethernet embedded switches:
    - Marvell (mv88e6xxx):
      - support RGMII cmode
    - NXP (felix):
      - standardized ethtool counters
    - Microchip (lan966x):
      - QoS queuing offload (tc-mqprio, tc-tbf, tc-cbs, tc-ets)
      - traffic policing and mirroring
      - link aggregation / bonding offload
      - QUSGMII PHY mode support
 
  - Qualcomm 802.11ax WiFi (ath11k):
    - cold boot calibration support on WCN6750
    - support to connect to a non-transmit MBSSID AP profile
    - enable remain-on-channel support on WCN6750
    - Wake-on-WLAN support for WCN6750
    - support to provide transmit power from firmware via nl80211
    - support to get power save duration for each client
    - spectral scan support for 160 MHz
 
  - MediaTek WiFi (mt76):
    - WiFi-to-Ethernet bridging offload for MT7986 chips
 
  - RealTek WiFi (rtw89):
    - P2P support
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-next-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Jakub Kicinski:
 "Core:

   - Introduce and use a single page frag cache for allocating small skb
     heads, clawing back the 10-20% performance regression in UDP flood
     test from previous fixes.

   - Run packets which already went thru HW coalescing thru SW GRO. This
     significantly improves TCP segment coalescing and simplifies
     deployments as different workloads benefit from HW or SW GRO.

   - Shrink the size of the base zero-copy send structure.

   - Move TCP init under a new slow / sleepable version of DO_ONCE().

  BPF:

   - Add BPF-specific, any-context-safe memory allocator.

   - Add helpers/kfuncs for PKCS#7 signature verification from BPF
     programs.

   - Define a new map type and related helpers for user space -> kernel
     communication over a ring buffer (BPF_MAP_TYPE_USER_RINGBUF).

   - Allow targeting BPF iterators to loop through resources of one
     task/thread.

   - Add ability to call selected destructive functions. Expose
     crash_kexec() to allow BPF to trigger a kernel dump. Use
     CAP_SYS_BOOT check on the loading process to judge permissions.

   - Enable BPF to collect custom hierarchical cgroup stats efficiently
     by integrating with the rstat framework.

   - Support struct arguments for trampoline based programs. Only
     structs with size <= 16B and x86 are supported.

   - Invoke cgroup/connect{4,6} programs for unprivileged ICMP ping
     sockets (instead of just TCP and UDP sockets).

   - Add a helper for accessing CLOCK_TAI for time sensitive network
     related programs.

   - Support accessing network tunnel metadata's flags.

   - Make TCP SYN ACK RTO tunable by BPF programs with TCP Fast Open.

   - Add support for writing to Netfilter's nf_conn:mark.

  Protocols:

   - WiFi: more Extremely High Throughput (EHT) and Multi-Link Operation
     (MLO) work (802.11be, WiFi 7).

   - vsock: improve support for SO_RCVLOWAT.

   - SMC: support SO_REUSEPORT.

   - Netlink: define and document how to use netlink in a "modern" way.
     Support reporting missing attributes via extended ACK.

   - IPSec: support collect metadata mode for xfrm interfaces.

   - TCPv6: send consistent autoflowlabel in SYN_RECV state and RST
     packets.

   - TCP: introduce optional per-netns connection hash table to allow
     better isolation between namespaces (opt-in, at the cost of memory
     and cache pressure).

   - MPTCP: support TCP_FASTOPEN_CONNECT.

   - Add NEXT-C-SID support in Segment Routing (SRv6) End behavior.

   - Adjust IP_UNICAST_IF sockopt behavior for connected UDP sockets.

   - Open vSwitch:
      - Allow specifying ifindex of new interfaces.
      - Allow conntrack and metering in non-initial user namespace.

   - TLS: support the Korean ARIA-GCM crypto algorithm.

   - Remove DECnet support.

  Driver API:

   - Allow selecting the conduit interface used by each port in DSA
     switches, at runtime.

   - Ethernet Power Sourcing Equipment and Power Device support.

   - Add tc-taprio support for queueMaxSDU parameter, i.e. setting per
     traffic class max frame size for time-based packet schedules.

   - Support PHY rate matching - adapting between differing host-side
     and link-side speeds.

   - Introduce QUSGMII PHY mode and 1000BASE-KX interface mode.

   - Validate OF (device tree) nodes for DSA shared ports; make
     phylink-related properties mandatory on DSA and CPU ports.
     Enforcing more uniformity should allow transitioning to phylink.

   - Require that flash component name used during update matches one of
     the components for which version is reported by info_get().

   - Remove "weight" argument from driver-facing NAPI API as much as
     possible. It's one of those magic knobs which seemed like a good
     idea at the time but is too indirect to use in practice.

   - Support offload of TLS connections with 256 bit keys.

  New hardware / drivers:

   - Ethernet:
      - Microchip KSZ9896 6-port Gigabit Ethernet Switch
      - Renesas Ethernet AVB (EtherAVB-IF) Gen4 SoCs
      - Analog Devices ADIN1110 and ADIN2111 industrial single pair
        Ethernet (10BASE-T1L) MAC+PHY.
      - Rockchip RV1126 Gigabit Ethernet (a version of stmmac IP).

   - Ethernet SFPs / modules:
      - RollBall / Hilink / Turris 10G copper SFPs
      - HALNy GPON module

   - WiFi:
      - CYW43439 SDIO chipset (brcmfmac)
      - CYW89459 PCIe chipset (brcmfmac)
      - BCM4378 on Apple platforms (brcmfmac)

  Drivers:

   - CAN:
      - gs_usb: HW timestamp support

   - Ethernet PHYs:
      - lan8814: cable diagnostics

   - Ethernet NICs:
      - Intel (100G):
         - implement control of FCS/CRC stripping
         - port splitting via devlink
         - L2TPv3 filtering offload
      - nVidia/Mellanox:
         - tunnel offload for sub-functions
         - MACSec offload, w/ Extended packet number and replay window
           offload
         - significantly restructure, and optimize the AF_XDP support,
           align the behavior with other vendors
      - Huawei:
         - configuring DSCP map for traffic class selection
         - querying standard FEC statistics
         - querying SerDes lane number via ethtool
      - Marvell/Cavium:
         - egress priority flow control
         - MACSec offload
      - AMD/SolarFlare:
         - PTP over IPv6 and raw Ethernet
      - small / embedded:
         - ax88772: convert to phylink (to support SFP cages)
         - altera: tse: convert to phylink
         - ftgmac100: support fixed link
         - enetc: standard Ethtool counters
         - macb: ZynqMP SGMII dynamic configuration support
         - tsnep: support multi-queue and use page pool
         - lan743x: Rx IP & TCP checksum offload
         - igc: add xdp frags support to ndo_xdp_xmit

   - Ethernet high-speed switches:
      - Marvell (prestera):
         - support SPAN port features (traffic mirroring)
         - nexthop object offloading
      - Microchip (sparx5):
         - multicast forwarding offload
         - QoS queuing offload (tc-mqprio, tc-tbf, tc-ets)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - support RGMII cmode
      - NXP (felix):
         - standardized ethtool counters
      - Microchip (lan966x):
         - QoS queuing offload (tc-mqprio, tc-tbf, tc-cbs, tc-ets)
         - traffic policing and mirroring
         - link aggregation / bonding offload
         - QUSGMII PHY mode support

   - Qualcomm 802.11ax WiFi (ath11k):
      - cold boot calibration support on WCN6750
      - support to connect to a non-transmit MBSSID AP profile
      - enable remain-on-channel support on WCN6750
      - Wake-on-WLAN support for WCN6750
      - support to provide transmit power from firmware via nl80211
      - support to get power save duration for each client
      - spectral scan support for 160 MHz

   - MediaTek WiFi (mt76):
      - WiFi-to-Ethernet bridging offload for MT7986 chips

   - RealTek WiFi (rtw89):
      - P2P support"

* tag 'net-next-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1864 commits)
  eth: pse: add missing static inlines
  once: rename _SLOW to _SLEEPABLE
  net: pse-pd: add regulator based PSE driver
  dt-bindings: net: pse-dt: add bindings for regulator based PoDL PSE controller
  ethtool: add interface to interact with Ethernet Power Equipment
  net: mdiobus: search for PSE nodes by parsing PHY nodes.
  net: mdiobus: fwnode_mdiobus_register_phy() rework error handling
  net: add framework to support Ethernet PSE and PDs devices
  dt-bindings: net: phy: add PoDL PSE property
  net: marvell: prestera: Propagate nh state from hw to kernel
  net: marvell: prestera: Add neighbour cache accounting
  net: marvell: prestera: add stub handler neighbour events
  net: marvell: prestera: Add heplers to interact with fib_notifier_info
  net: marvell: prestera: Add length macros for prestera_ip_addr
  net: marvell: prestera: add delayed wq and flush wq on deinit
  net: marvell: prestera: Add strict cleanup of fib arbiter
  net: marvell: prestera: Add cleanup of allocated fib_nodes
  net: marvell: prestera: Add router nexthops ABI
  eth: octeon: fix build after netif_napi_add() changes
  net/mlx5: E-Switch, Return EBUSY if can't get mode lock
  ...
2022-10-04 13:38:03 -07:00
Bagas Sanjaya
736baae643 Documentation: bpf: Add implementation notes documentations to table of contents
Sphinx reported warnings on missing implementation notes documentations in the
table of contents:

Documentation/bpf/clang-notes.rst: WARNING: document isn't included in any toctree
Documentation/bpf/linux-notes.rst: WARNING: document isn't included in any toctree

Add these documentations to the table of contents (index.rst) of BPF
documentation to fix the warnings.

Link: https://lore.kernel.org/linux-doc/202210020749.yfgDZbRL-lkp@intel.com/
Fixes: 6c7aaffb24 ("bpf, docs: Move Clang notes to a separate file")
Fixes: 6166da0a02 ("bpf, docs: Move legacy packet instructions to a separate file")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Link: https://lore.kernel.org/r/20221002032022.24693-1-bagasdotme@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-10-03 09:16:52 -07:00
Alexei Starovoitov
b502a6fb46 bpf, docs: Delete misformatted table.
Delete misformatted table.

Fixes: 6166da0a02 ("bpf, docs: Move legacy packet instructions to a separate file")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-10-01 08:51:26 -07:00
Dave Thaler
5a8921ba96 bpf, docs: Add TOC and fix formatting.
Add TOC and fix formatting.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Link: https://lore.kernel.org/r/20220927185958.14995-5-dthaler1968@googlemail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-30 13:41:36 -07:00
Dave Thaler
ee159bdbdb bpf, docs: Add Clang note about BPF_ALU
Add Clang note about BPF_ALU.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Link: https://lore.kernel.org/r/20220927185958.14995-4-dthaler1968@googlemail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-30 13:41:25 -07:00
Dave Thaler
6c7aaffb24 bpf, docs: Move Clang notes to a separate file
Move Clang notes to a separate file.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Link: https://lore.kernel.org/r/20220927185958.14995-3-dthaler1968@googlemail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-30 13:41:13 -07:00
Dave Thaler
9a0bf21337 bpf, docs: Linux byteswap note
Add Linux byteswap note.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Link: https://lore.kernel.org/r/20220927185958.14995-2-dthaler1968@googlemail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-30 13:40:59 -07:00