Documentation/bpf/llvm_reloc.rst

7 This document describes LLVM BPF backend relocation types.
9 Relocation Record
12 LLVM BPF backend records each relocation with the following 16-byte
18     Elf64_Xword   r_info;    // Relocation type and symbol index.
55   Relocation section '.rel.text' at offset 0x190 contains 4 entries:
62 Each relocation is represented by ``Offset`` (8 bytes) and ``Info`` (8 bytes).
63 For example, the first relocation corresponds to the first instruction
64 (Offset 0x0) and the corresponding ``Info`` indicates the relocation type
81 Similarly, the second relocation is at ``.text`` offset ``0x18``, instruction 3,
83 The second relocation resolves to global variable ``g2`` which has a symbol
103 Different Relocation Types
106 Six relocation types are supported. The following is an overview and
117 For example, ``R_BPF_64_64`` relocation type is used for ``ld_imm64`` instruction.
120 data bitsize is 32 (4 bytes). The relocation can be resolved with
125 In another case, ``R_BPF_64_ABS64`` relocation type is used for normal 64-bit data.
127 bitsize is 64 (8 bytes). The relocation can be resolved with
194 The first relocation corresponds to ``gfunc(a, b)`` where ``gfunc`` has a value of 0,
196 The second relocation corresponds to ``lfunc(a, b)`` where ``lfunc`` has a section
198 The third relocation corresponds to ld_imm64 of ``global``, which has a section
207 relocation below in ``.data`` section with command
210   Relocation section '.rel.data' at offset 0x458 contains 1 entries:
214 The relocation says the first 8-byte of ``.data`` section should be
220   Relocation section '.rel.debug_info' at offset 0x468 contains 13 entries:
235   Relocation section '.rel.BTF' at offset 0x538 contains 1 entries:
239   Relocation section '.rel.BTF.ext' at offset 0x548 contains 2 entries:
251 of CO-RE specific relocation records. These relocation records are not
266 Relocation kinds
284 The complete list of relocation kinds is represented by the following enum:
347 CO-RE Relocation Record
350 Relocation record is encoded as the following structure:
362   associated with this relocation;
368   String interpretation depends on specific relocation kind:
414 CO-RE Relocation Examples
464 All relocation kinds could be requested via built-in functions.