cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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bpftool-link.rst (2883B)

      1.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
      2
      3================
      4bpftool-link
      5================
      6-------------------------------------------------------------------------------
      7tool for inspection and simple manipulation of eBPF links
      8-------------------------------------------------------------------------------
      9
     10:Manual section: 8
     11
     12.. include:: substitutions.rst
     13
     14SYNOPSIS
     15========
     16
     17	**bpftool** [*OPTIONS*] **link** *COMMAND*
     18
     19	*OPTIONS* := { |COMMON_OPTIONS| | { **-f** | **--bpffs** } | { **-n** | **--nomount** } }
     20
     21	*COMMANDS* := { **show** | **list** | **pin** | **help** }
     22
     23LINK COMMANDS
     24=============
     25
     26|	**bpftool** **link { show | list }** [*LINK*]
     27|	**bpftool** **link pin** *LINK* *FILE*
     28|	**bpftool** **link detach** *LINK*
     29|	**bpftool** **link help**
     30|
     31|	*LINK* := { **id** *LINK_ID* | **pinned** *FILE* }
     32
     33
     34DESCRIPTION
     35===========
     36	**bpftool link { show | list }** [*LINK*]
     37		  Show information about active links. If *LINK* is
     38		  specified show information only about given link,
     39		  otherwise list all links currently active on the system.
     40
     41		  Output will start with link ID followed by link type and
     42		  zero or more named attributes, some of which depend on type
     43		  of link.
     44
     45		  Since Linux 5.8 bpftool is able to discover information about
     46		  processes that hold open file descriptors (FDs) against BPF
     47		  links. On such kernels bpftool will automatically emit this
     48		  information as well.
     49
     50	**bpftool link pin** *LINK* *FILE*
     51		  Pin link *LINK* as *FILE*.
     52
     53		  Note: *FILE* must be located in *bpffs* mount. It must not
     54		  contain a dot character ('.'), which is reserved for future
     55		  extensions of *bpffs*.
     56
     57	**bpftool link detach** *LINK*
     58		  Force-detach link *LINK*. BPF link and its underlying BPF
     59		  program will stay valid, but they will be detached from the
     60		  respective BPF hook and BPF link will transition into
     61		  a defunct state until last open file descriptor for that
     62		  link is closed.
     63
     64	**bpftool link help**
     65		  Print short help message.
     66
     67OPTIONS
     68=======
     69	.. include:: common_options.rst
     70
     71	-f, --bpffs
     72		  When showing BPF links, show file names of pinned
     73		  links.
     74
     75	-n, --nomount
     76		  Do not automatically attempt to mount any virtual file system
     77		  (such as tracefs or BPF virtual file system) when necessary.
     78
     79EXAMPLES
     80========
     81**# bpftool link show**
     82
     83::
     84
     85    10: cgroup  prog 25
     86            cgroup_id 614  attach_type egress
     87            pids test_progs(223)
     88
     89**# bpftool --json --pretty link show**
     90
     91::
     92
     93    [{
     94            "type": "cgroup",
     95            "prog_id": 25,
     96            "cgroup_id": 614,
     97            "attach_type": "egress",
     98            "pids": [{
     99                    "pid": 223,
    100                    "comm": "test_progs"
    101                }
    102            ]
    103        }
    104    ]
    105
    106|
    107| **# bpftool link pin id 10 /sys/fs/bpf/link**
    108| **# ls -l /sys/fs/bpf/**
    109
    110::
    111
    112    -rw------- 1 root root 0 Apr 23 21:39 link