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diff --git a/Documentation/bpf/btf.rst b/Documentation/bpf/btf.rst
index 29396e6943b0..8820360d00da 100644
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+++ b/Documentation/bpf/btf.rst
@@ -578,6 +578,7 @@ For line_info, the line number and column number are defined as below:
#define BPF_LINE_INFO_LINE_COL(line_col) ((line_col) & 0x3ff)
3.4 BPF_{PROG,MAP}_GET_NEXT_ID
+==============================
In kernel, every loaded program, map or btf has a unique id. The id won't
change during the lifetime of a program, map, or btf.
@@ -587,6 +588,7 @@ each command, to user space, for bpf program or maps, respectively, so an
inspection tool can inspect all programs and maps.
3.5 BPF_{PROG,MAP}_GET_FD_BY_ID
+===============================
An introspection tool cannot use id to get details about program or maps.
A file descriptor needs to be obtained first for reference-counting purpose.