Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Alexei Starovoitov says:

====================
pull-request: bpf-next 2023-07-13

We've added 67 non-merge commits during the last 15 day(s) which contain
a total of 106 files changed, 4444 insertions(+), 619 deletions(-).

The main changes are:

1) Fix bpftool build in presence of stale vmlinux.h,
   from Alexander Lobakin.

2) Introduce bpf_me_mcache_free_rcu() and fix OOM under stress,
   from Alexei Starovoitov.

3) Teach verifier actual bounds of bpf_get_smp_processor_id()
   and fix perf+libbpf issue related to custom section handling,
   from Andrii Nakryiko.

4) Introduce bpf map element count, from Anton Protopopov.

5) Check skb ownership against full socket, from Kui-Feng Lee.

6) Support for up to 12 arguments in BPF trampoline, from Menglong Dong.

7) Export rcu_request_urgent_qs_task, from Paul E. McKenney.

8) Fix BTF walking of unions, from Yafang Shao.

9) Extend link_info for kprobe_multi and perf_event links,
   from Yafang Shao.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (67 commits)
  selftests/bpf: Add selftest for PTR_UNTRUSTED
  bpf: Fix an error in verifying a field in a union
  selftests/bpf: Add selftests for nested_trust
  bpf: Fix an error around PTR_UNTRUSTED
  selftests/bpf: add testcase for TRACING with 6+ arguments
  bpf, x86: allow function arguments up to 12 for TRACING
  bpf, x86: save/restore regs with BPF_DW size
  bpftool: Use "fallthrough;" keyword instead of comments
  bpf: Add object leak check.
  bpf: Convert bpf_cpumask to bpf_mem_cache_free_rcu.
  bpf: Introduce bpf_mem_free_rcu() similar to kfree_rcu().
  selftests/bpf: Improve test coverage of bpf_mem_alloc.
  rcu: Export rcu_request_urgent_qs_task()
  bpf: Allow reuse from waiting_for_gp_ttrace list.
  bpf: Add a hint to allocated objects.
  bpf: Change bpf_mem_cache draining process.
  bpf: Further refactor alloc_bulk().
  bpf: Factor out inc/dec of active flag into helpers.
  bpf: Refactor alloc_bulk().
  bpf: Let free_all() return the number of freed elements.
  ...
====================

Link: https://lore.kernel.org/r/20230714020910.80794-1-alexei.starovoitov@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

7 files changed, 32 insertions, 14 deletions

diff --git a/Documentation/bpf/bpf_devel_QA.rst b/Documentation/bpf/bpf_devel_QA.rst
index 609b71f5747d..de27e1620821 100644
--- a/Documentation/bpf/bpf_devel_QA.rst
+++ b/Documentation/bpf/bpf_devel_QA.rst
@@ -635,12 +635,12 @@ test coverage.
 
 Q: clang flag for target bpf?
 -----------------------------
-Q: In some cases clang flag ``-target bpf`` is used but in other cases the
+Q: In some cases clang flag ``--target=bpf`` is used but in other cases the
 default clang target, which matches the underlying architecture, is used.
 What is the difference and when I should use which?
 
 A: Although LLVM IR generation and optimization try to stay architecture
-independent, ``-target <arch>`` still has some impact on generated code:
+independent, ``--target=<arch>`` still has some impact on generated code:
 
 - BPF program may recursively include header file(s) with file scope
   inline assembly codes. The default target can handle this well,
@@ -658,7 +658,7 @@ independent, ``-target <arch>`` still has some impact on generated code:
   The clang option ``-fno-jump-tables`` can be used to disable
   switch table generation.
 
-- For clang ``-target bpf``, it is guaranteed that pointer or long /
+- For clang ``--target=bpf``, it is guaranteed that pointer or long /
   unsigned long types will always have a width of 64 bit, no matter
   whether underlying clang binary or default target (or kernel) is
   32 bit. However, when native clang target is used, then it will
@@ -668,7 +668,7 @@ independent, ``-target <arch>`` still has some impact on generated code:
   while the BPF LLVM back end still operates in 64 bit. The native
   target is mostly needed in tracing for the case of walking ``pt_regs``
   or other kernel structures where CPU's register width matters.
-  Otherwise, ``clang -target bpf`` is generally recommended.
+  Otherwise, ``clang --target=bpf`` is generally recommended.
 
 You should use default target when:
 
@@ -685,7 +685,7 @@ when:
   into these structures is verified by the BPF verifier and may result
   in verification failures if the native architecture is not aligned with
   the BPF architecture, e.g. 64-bit. An example of this is
-  BPF_PROG_TYPE_SK_MSG require ``-target bpf``
+  BPF_PROG_TYPE_SK_MSG require ``--target=bpf``
 
 
 .. Links
diff --git a/Documentation/bpf/btf.rst b/Documentation/bpf/btf.rst
index 7cd7c5415a99..f32db1f44ae9 100644
--- a/Documentation/bpf/btf.rst
+++ b/Documentation/bpf/btf.rst
@@ -990,7 +990,7 @@ format.::
     } g2;
     int main() { return 0; }
     int test() { return 0; }
-    -bash-4.4$ clang -c -g -O2 -target bpf t2.c
+    -bash-4.4$ clang -c -g -O2 --target=bpf t2.c
     -bash-4.4$ readelf -S t2.o
       ......
       [ 8] .BTF              PROGBITS         0000000000000000  00000247
@@ -1000,7 +1000,7 @@ format.::
       [10] .rel.BTF.ext      REL              0000000000000000  000007e0
            0000000000000040  0000000000000010          16     9     8
       ......
-    -bash-4.4$ clang -S -g -O2 -target bpf t2.c
+    -bash-4.4$ clang -S -g -O2 --target=bpf t2.c
     -bash-4.4$ cat t2.s
       ......
             .section        .BTF,"",@progbits
diff --git a/Documentation/bpf/index.rst b/Documentation/bpf/index.rst
index dbb39e8f9889..1ff177b89d66 100644
--- a/Documentation/bpf/index.rst
+++ b/Documentation/bpf/index.rst
@@ -12,9 +12,9 @@ that goes into great technical depth about the BPF Architecture.
 .. toctree::
    :maxdepth: 1
 
-   instruction-set
    verifier
    libbpf/index
+   standardization/index
    btf
    faq
    syscall_api
@@ -29,7 +29,6 @@ that goes into great technical depth about the BPF Architecture.
    bpf_licensing
    test_debug
    clang-notes
-   linux-notes
    other
    redirect
 
diff --git a/Documentation/bpf/llvm_reloc.rst b/Documentation/bpf/llvm_reloc.rst
index e4a777a6a3a2..450e6403fe3d 100644
--- a/Documentation/bpf/llvm_reloc.rst
+++ b/Documentation/bpf/llvm_reloc.rst
@@ -28,7 +28,7 @@ For example, for the following code::
     return g1 + g2 + l1 + l2;
   }
 
-Compiled with ``clang -target bpf -O2 -c test.c``, the following is
+Compiled with ``clang --target=bpf -O2 -c test.c``, the following is
 the code with ``llvm-objdump -dr test.o``::
 
        0:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
@@ -157,7 +157,7 @@ and ``call`` instructions. For example::
     return gfunc(a, b) +  lfunc(a, b) + global;
   }
 
-Compiled with ``clang -target bpf -O2 -c test.c``, we will have
+Compiled with ``clang --target=bpf -O2 -c test.c``, we will have
 following code with `llvm-objdump -dr test.o``::
 
   Disassembly of section .text:
@@ -203,7 +203,7 @@ The following is an example to show how R_BPF_64_ABS64 could be generated::
   int global() { return 0; }
   struct t { void *g; } gbl = { global };
 
-Compiled with ``clang -target bpf -O2 -g -c test.c``, we will see a
+Compiled with ``clang --target=bpf -O2 -g -c test.c``, we will see a
 relocation below in ``.data`` section with command
 ``llvm-readelf -r test.o``::
 
diff --git a/Documentation/bpf/standardization/index.rst b/Documentation/bpf/standardization/index.rst
new file mode 100644
index 000000000000..09c6ba055fd7
--- /dev/null
+++ b/Documentation/bpf/standardization/index.rst
@@ -0,0 +1,18 @@
+.. SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+
+===================
+BPF Standardization
+===================
+
+This directory contains documents that are being iterated on as part of the BPF
+standardization effort with the IETF. See the `IETF BPF Working Group`_ page
+for the working group charter, documents, and more.
+
+.. toctree::
+   :maxdepth: 1
+
+   instruction-set
+   linux-notes
+
+.. Links:
+.. _IETF BPF Working Group: https://datatracker.ietf.org/wg/bpf/about/
diff --git a/Documentation/bpf/instruction-set.rst b/Documentation/bpf/standardization/instruction-set.rst
index 6644842cd3ea..751e657973f0 100644
--- a/Documentation/bpf/instruction-set.rst
+++ b/Documentation/bpf/standardization/instruction-set.rst
@@ -165,7 +165,7 @@ BPF_OR    0x40   dst \|= src
 BPF_AND   0x50   dst &= src
 BPF_LSH   0x60   dst <<= (src & mask)
 BPF_RSH   0x70   dst >>= (src & mask)
-BPF_NEG   0x80   dst = ~src
+BPF_NEG   0x80   dst = -src
 BPF_MOD   0x90   dst = (src != 0) ? (dst % src) : dst
 BPF_XOR   0xa0   dst ^= src
 BPF_MOV   0xb0   dst = src
diff --git a/Documentation/bpf/linux-notes.rst b/Documentation/bpf/standardization/linux-notes.rst
index 508d009d3bed..00d2693de025 100644
--- a/Documentation/bpf/linux-notes.rst
+++ b/Documentation/bpf/standardization/linux-notes.rst
@@ -45,7 +45,8 @@ On Linux, this integer is a BTF ID.
 Legacy BPF Packet access instructions
 =====================================
 
-As mentioned in the `ISA standard documentation <instruction-set.rst#legacy-bpf-packet-access-instructions>`_,
+As mentioned in the `ISA standard documentation
+<instruction-set.html#legacy-bpf-packet-access-instructions>`_,
 Linux has special eBPF instructions for access to packet data that have been
 carried over from classic BPF to retain the performance of legacy socket
 filters running in the eBPF interpreter.