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author | Paul E. McKenney <paulmck@kernel.org> | 2022-08-02 10:39:12 -0700 |
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committer | Alexei Starovoitov <ast@kernel.org> | 2022-08-04 13:17:24 -0700 |
commit | 62fc770d90ef5a92931deb477c384f82be122a18 (patch) | |
tree | 32eeb350c15080dca3e91d23dcb60ddb72cdc177 /Documentation/bpf | |
parent | b9b738eeafe54d960ccb240fc1b0c5031a0d76f5 (diff) | |
download | linux-stable-62fc770d90ef5a92931deb477c384f82be122a18.tar.gz linux-stable-62fc770d90ef5a92931deb477c384f82be122a18.tar.bz2 linux-stable-62fc770d90ef5a92931deb477c384f82be122a18.zip |
bpf: Update bpf_design_QA.rst to clarify that attaching to functions is not ABI
This patch updates bpf_design_QA.rst to clarify that the ability to
attach a BPF program to an arbitrary function in the kernel does not
make that function become part of the Linux kernel's ABI.
[ paulmck: Apply Daniel Borkmann feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20220802173913.4170192-2-paulmck@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'Documentation/bpf')
-rw-r--r-- | Documentation/bpf/bpf_design_QA.rst | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/Documentation/bpf/bpf_design_QA.rst b/Documentation/bpf/bpf_design_QA.rst index 2ed9128cfbec..a06ae8a828e3 100644 --- a/Documentation/bpf/bpf_design_QA.rst +++ b/Documentation/bpf/bpf_design_QA.rst @@ -279,3 +279,15 @@ cc (congestion-control) implementations. If any of these kernel functions has changed, both the in-tree and out-of-tree kernel tcp cc implementations have to be changed. The same goes for the bpf programs and they have to be adjusted accordingly. + +Q: Attaching to arbitrary kernel functions is an ABI? +----------------------------------------------------- +Q: BPF programs can be attached to many kernel functions. Do these +kernel functions become part of the ABI? + +A: NO. + +The kernel function prototypes will change, and BPF programs attaching to +them will need to change. The BPF compile-once-run-everywhere (CO-RE) +should be used in order to make it easier to adapt your BPF programs to +different versions of the kernel. |