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  1. 18 12月, 2018 4 次提交
    • Y
      bpf: enable cgroup local storage map pretty print with kind_flag · ffa0c1cf
      由 Yonghong Song 提交于 
      Commit 970289fc0a83 ("bpf: add bpffs pretty print for cgroup
local storage maps") added bpffs pretty print for cgroup
local storage maps. The commit worked for struct without kind_flag
set.

This patch refactored and made pretty print also work
with kind_flag set for the struct.
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NYonghong Song <yhs@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      ffa0c1cf
    • Y
      bpf: btf: fix struct/union/fwd types with kind_flag · 9d5f9f70
      由 Yonghong Song 提交于 
      This patch fixed two issues with BTF. One is related to
struct/union bitfield encoding and the other is related to
forward type.

Issue #1 and solution:

======================

Current btf encoding of bitfield follows what pahole generates.
For each bitfield, pahole will duplicate the type chain and
put the bitfield size at the final int or enum type.
Since the BTF enum type cannot encode bit size,
pahole workarounds the issue by generating
an int type whenever the enum bit size is not 32.

For example,
  -bash-4.4$ cat t.c
  typedef int ___int;
  enum A { A1, A2, A3 };
  struct t {
    int a[5];
    ___int b:4;
    volatile enum A c:4;
  } g;
  -bash-4.4$ gcc -c -O2 -g t.c
The current kernel supports the following BTF encoding:
  $ pahole -JV t.o
  [1] TYPEDEF ___int type_id=2
  [2] INT int size=4 bit_offset=0 nr_bits=32 encoding=SIGNED
  [3] ENUM A size=4 vlen=3
        A1 val=0
        A2 val=1
        A3 val=2
  [4] STRUCT t size=24 vlen=3
        a type_id=5 bits_offset=0
        b type_id=9 bits_offset=160
        c type_id=11 bits_offset=164
  [5] ARRAY (anon) type_id=2 index_type_id=2 nr_elems=5
  [6] INT sizetype size=8 bit_offset=0 nr_bits=64 encoding=(none)
  [7] VOLATILE (anon) type_id=3
  [8] INT int size=1 bit_offset=0 nr_bits=4 encoding=(none)
  [9] TYPEDEF ___int type_id=8
  [10] INT (anon) size=1 bit_offset=0 nr_bits=4 encoding=SIGNED
  [11] VOLATILE (anon) type_id=10

Two issues are in the above:
  . by changing enum type to int, we lost the original
    type information and this will not be ideal later
    when we try to convert BTF to a header file.
  . the type duplication for bitfields will cause
    BTF bloat. Duplicated types cannot be deduplicated
    later if the bitfield size is different.

To fix this issue, this patch implemented a compatible
change for BTF struct type encoding:
  . the bit 31 of struct_type->info, previously reserved,
    now is used to indicate whether bitfield_size is
    encoded in btf_member or not.
  . if bit 31 of struct_type->info is set,
    btf_member->offset will encode like:
      bit 0 - 23: bit offset
      bit 24 - 31: bitfield size
    if bit 31 is not set, the old behavior is preserved:
      bit 0 - 31: bit offset

So if the struct contains a bit field, the maximum bit offset
will be reduced to (2^24 - 1) instead of MAX_UINT. The maximum
bitfield size will be 256 which is enough for today as maximum
bitfield in compiler can be 128 where int128 type is supported.

This kernel patch intends to support the new BTF encoding:
  $ pahole -JV t.o
  [1] TYPEDEF ___int type_id=2
  [2] INT int size=4 bit_offset=0 nr_bits=32 encoding=SIGNED
  [3] ENUM A size=4 vlen=3
        A1 val=0
        A2 val=1
        A3 val=2
  [4] STRUCT t kind_flag=1 size=24 vlen=3
        a type_id=5 bitfield_size=0 bits_offset=0
        b type_id=1 bitfield_size=4 bits_offset=160
        c type_id=7 bitfield_size=4 bits_offset=164
  [5] ARRAY (anon) type_id=2 index_type_id=2 nr_elems=5
  [6] INT sizetype size=8 bit_offset=0 nr_bits=64 encoding=(none)
  [7] VOLATILE (anon) type_id=3

Issue #2 and solution:
======================

Current forward type in BTF does not specify whether the original
type is struct or union. This will not work for type pretty print
and BTF-to-header-file conversion as struct/union must be specified.
  $ cat tt.c
  struct t;
  union u;
  int foo(struct t *t, union u *u) { return 0; }
  $ gcc -c -g -O2 tt.c
  $ pahole -JV tt.o
  [1] INT int size=4 bit_offset=0 nr_bits=32 encoding=SIGNED
  [2] FWD t type_id=0
  [3] PTR (anon) type_id=2
  [4] FWD u type_id=0
  [5] PTR (anon) type_id=4

To fix this issue, similar to issue #1, type->info bit 31
is used. If the bit is set, it is union type. Otherwise, it is
a struct type.

  $ pahole -JV tt.o
  [1] INT int size=4 bit_offset=0 nr_bits=32 encoding=SIGNED
  [2] FWD t kind_flag=0 type_id=0
  [3] PTR (anon) kind_flag=0 type_id=2
  [4] FWD u kind_flag=1 type_id=0
  [5] PTR (anon) kind_flag=0 type_id=4

Pahole/LLVM change:
===================

The new kind_flag functionality has been implemented in pahole
and llvm:
  https://github.com/yonghong-song/pahole/tree/bitfield
  https://github.com/yonghong-song/llvm/tree/bitfield

Note that pahole hasn't implemented func/func_proto kind
and .BTF.ext. So to print function signature with bpftool,
the llvm compiler should be used.

Fixes: 69b693f0 ("bpf: btf: Introduce BPF Type Format (BTF)")
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NYonghong Song <yhs@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      9d5f9f70
    • Y
      bpf: btf: refactor btf_int_bits_seq_show() · f97be3ab
      由 Yonghong Song 提交于 
      Refactor function btf_int_bits_seq_show() by creating
function btf_bitfield_seq_show() which has no dependence
on btf and btf_type. The function btf_bitfield_seq_show()
will be in later patch to directly dump bitfield member values.
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NYonghong Song <yhs@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      f97be3ab
    • D
      bpf: remove useless version check for prog load · 6c4fc209
      由 Daniel Borkmann 提交于 
      Existing libraries and tracing frameworks work around this kernel
version check by automatically deriving the kernel version from
uname(3) or similar such that the user does not need to do it
manually; these workarounds also make the version check useless
at the same time.

Moreover, most other BPF tracing types enabling bpf_probe_read()-like
functionality have /not/ adapted this check, and in general these
days it is well understood anyway that all the tracing programs are
not stable with regards to future kernels as kernel internal data
structures are subject to change from release to release.

Back at last netconf we discussed [0] and agreed to remove this
check from bpf_prog_load() and instead document it here in the uapi
header that there is no such guarantee for stable API for these
programs.

  [0] http://vger.kernel.org/netconf2018_files/DanielBorkmann_netconf2018.pdfSigned-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NQuentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
      6c4fc209
  3. 15 12月, 2018 14 次提交
  5. 14 12月, 2018 2 次提交
  7. 13 12月, 2018 13 次提交
  9. 12 12月, 2018 2 次提交
  11. 11 12月, 2018 5 次提交
    • D
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next · addb0679
      由 David S. Miller 提交于 
      Daniel Borkmann says:

====================
pull-request: bpf-next 2018-12-11

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

It has three minor merge conflicts, resolutions:

1) tools/testing/selftests/bpf/test_verifier.c

 Take first chunk with alignment_prevented_execution.

2) net/core/filter.c

  [...]
  case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
  case bpf_ctx_range(struct __sk_buff, wire_len):
        return false;
  [...]

3) include/uapi/linux/bpf.h

  Take the second chunk for the two cases each.

The main changes are:

1) Add support for BPF line info via BTF and extend libbpf as well
   as bpftool's program dump to annotate output with BPF C code to
   facilitate debugging and introspection, from Martin.

2) Add support for BPF_ALU | BPF_ARSH | BPF_{K,X} in interpreter
   and all JIT backends, from Jiong.

3) Improve BPF test coverage on archs with no efficient unaligned
   access by adding an "any alignment" flag to the BPF program load
   to forcefully disable verifier alignment checks, from David.

4) Add a new bpf_prog_test_run_xattr() API to libbpf which allows for
   proper use of BPF_PROG_TEST_RUN with data_out, from Lorenz.

5) Extend tc BPF programs to use a new __sk_buff field called wire_len
   for more accurate accounting of packets going to wire, from Petar.

6) Improve bpftool to allow dumping the trace pipe from it and add
   several improvements in bash completion and map/prog dump,
   from Quentin.

7) Optimize arm64 BPF JIT to always emit movn/movk/movk sequence for
   kernel addresses and add a dedicated BPF JIT backend allocator,
   from Ard.

8) Add a BPF helper function for IR remotes to report mouse movements,
   from Sean.

9) Various cleanups in BPF prog dump e.g. to make UAPI bpf_prog_info
   member naming consistent with existing conventions, from Yonghong
   and Song.

10) Misc cleanups and improvements in allowing to pass interface name
    via cmdline for xdp1 BPF example, from Matteo.

11) Fix a potential segfault in BPF sample loader's kprobes handling,
    from Daniel T.

12) Fix SPDX license in libbpf's README.rst, from Andrey.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      addb0679
    • D
      neighbor: gc_list changes should be protected by table lock · 8cc196d6
      由 David Ahern 提交于 
      Adding and removing neighbor entries to / from the gc_list need to be
done while holding the table lock; a couple of places were missed in the
original patch.

Move the list_add_tail in neigh_alloc to ___neigh_create where the lock
is already obtained. Since neighbor entries should rarely be moved
to/from PERMANENT state, add lock/unlock around the gc_list changes in
neigh_change_state rather than extending the lock hold around all
neighbor updates.

Fixes: 58956317 ("neighbor: Improve garbage collection")
Reported-by: NAndrei Vagin <avagin@gmail.com>
Reported-by: syzbot+6cc2fd1d3bdd2e007363@syzkaller.appspotmail.com
Reported-by: syzbot+35e87b87c00f386b041f@syzkaller.appspotmail.com
Reported-by: syzbot+b354d1fb59091ea73c37@syzkaller.appspotmail.com
Reported-by: syzbot+3ddead5619658537909b@syzkaller.appspotmail.com
Reported-by: syzbot+424d47d5c456ce8b2bbe@syzkaller.appspotmail.com
Reported-by: syzbot+e4d42eb35f6a27b0a628@syzkaller.appspotmail.com
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      8cc196d6
    • D
      Merge tag 'mlx5e-updates-2018-12-10' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux · 93698321
      由 David S. Miller 提交于 
      Saeed Mahameed:

====================
mlx5e-updates-2018-12-10 (gre)

This patch set adds GRE offloading support to Mellanox ethernet driver.

Patches 1-5 replace the existing egdev mechanism with the new TC indirect
block binds mechanism that was introduced by Netronome:
7f76fa36 ("net: sched: register callbacks for indirect tc block binds")

Patches 6-9 add GRE offloading support along with some required
refactoring work.

Patch 10, Add netif_is_gretap()/netif_is_ip6gretap()
 - Changed the is_gretap_dev and is_ip6gretap_dev logic from structure
   comparison to string comparison of the rtnl_link_ops kind field.

Patch 11, add GRE offloading support to mlx5.

Patch 12 removes the egdev mechanism from TC as it is no longer used by
any of the drivers.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      93698321
    • O
      net/sched: Remove egdev mechanism · 69bd4840
      由 Oz Shlomo 提交于 
      The egdev mechanism was replaced by the TC indirect block notifications
platform.
Signed-off-by: NOz Shlomo <ozsh@mellanox.com>
Reviewed-by: NEli Britstein <elibr@mellanox.com>
Reviewed-by: NJiri Pirko <jiri@mellanox.com>
Cc: John Hurley <john.hurley@netronome.com>
Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NSaeed Mahameed <saeedm@mellanox.com>
      69bd4840
    • O
      net/mlx5e: Add GRE protocol offloading · df2ef3bf
      由 Oz Shlomo 提交于 
      Add HW offloading support for TC flower filters configured on
gretap/ip6gretap net devices.
Signed-off-by: NOz Shlomo <ozsh@mellanox.com>
Reviewed-by: NEli Britstein <elibr@mellanox.com>
Signed-off-by: NSaeed Mahameed <saeedm@mellanox.com>
      df2ef3bf