queue-5.1/tools-bpftool-move-set_max_rlimit-before-__bpf_objec.patch

   1 From b9f2becf900b7cf3e9e361263701af44c87ccd50 Mon Sep 17 00:00:00 2001
   2 From: Yonghong Song <yhs@fb.com>
   3 Date: Thu, 16 May 2019 10:17:31 -0700
   4 Subject: tools/bpftool: move set_max_rlimit() before
   5  __bpf_object__open_xattr()
   6
   7 [ Upstream commit ac4e0e055fee5751c78bba1fc9ce508a6874d916 ]
   8
   9 For a host which has a lower rlimit for max locked memory (e.g., 64KB),
  10 the following error occurs in one of our production systems:
  11   # /usr/sbin/bpftool prog load /paragon/pods/52877437/home/mark.o \
  12     /sys/fs/bpf/paragon_mark_21 type cgroup/skb \
  13     map idx 0 pinned /sys/fs/bpf/paragon_map_21
  14   libbpf: Error in bpf_object__probe_name():Operation not permitted(1).
  15     Couldn't load basic 'r0 = 0' BPF program.
  16   Error: failed to open object file
  17
  18 The reason is due to low locked memory during bpf_object__probe_name()
  19 which probes whether program name is supported in kernel or not
  20 during __bpf_object__open_xattr().
  21
  22 bpftool program load already tries to relax mlock rlimit before
  23 bpf_object__load(). Let us move set_max_rlimit() before
  24 __bpf_object__open_xattr(), which fixed the issue here.
  25
  26 Fixes: 47eff61777c7 ("bpf, libbpf: introduce bpf_object__probe_caps to test BPF capabilities")
  27 Signed-off-by: Yonghong Song <yhs@fb.com>
  28 Signed-off-by: Alexei Starovoitov <ast@kernel.org>
  29 Signed-off-by: Sasha Levin <sashal@kernel.org>
  30 ---
  31  tools/bpf/bpftool/prog.c | 4 ++--
  32  1 file changed, 2 insertions(+), 2 deletions(-)
  33
  34 diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
  35 index d2be5a06c339..ed8ef5c82256 100644
  36 --- a/tools/bpf/bpftool/prog.c
  37 +++ b/tools/bpf/bpftool/prog.c
  38 @@ -873,6 +873,8 @@ static int load_with_options(int argc, char **argv, bool first_prog_only)
  39                 }
  40         }
  41
  42 +       set_max_rlimit();
  43 +
  44         obj = __bpf_object__open_xattr(&attr, bpf_flags);
  45         if (IS_ERR_OR_NULL(obj)) {
  46                 p_err("failed to open object file");
  47 @@ -952,8 +954,6 @@ static int load_with_options(int argc, char **argv, bool first_prog_only)
  48                 goto err_close_obj;
  49         }
  50
  51 -       set_max_rlimit();
  52 -
  53         err = bpf_object__load(obj);
  54         if (err) {
  55                 p_err("failed to load object file");
  56 --
  57 2.20.1
  58