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| author |   Ilya Leoshkevich <iii@linux.ibm.com> | 2022-07-26 15:40:07 +0200 |
|---|---|---|
| committer |   Daniel Borkmann <daniel@iogearbox.net> | 2022-07-26 16:27:21 +0200 |
| commit | 2d369b4b0044d4f6a3fa4071807f66eced0f2725 (patch) | |
| tree | 230afac9de6950bd483f249788b1045d7a30297a /tools/lib/bpf/bpf_tracing.h | |
| parent | bpf, devmap: Compute proper xdp_frame len redirecting frames (diff) | |
| download | linux-dev-2d369b4b0044d4f6a3fa4071807f66eced0f2725.tar.xz linux-dev-2d369b4b0044d4f6a3fa4071807f66eced0f2725.zip | |
libbpf: Extend BPF_KSYSCALL documentation
Explicitly list known quirks. Mention that socket-related syscalls can be
invoked via socketcall().
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20220726134008.256968-2-iii@linux.ibm.com
Diffstat (limited to '')
| -rw-r--r-- | tools/lib/bpf/bpf_tracing.h | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/tools/lib/bpf/bpf_tracing.h b/tools/lib/bpf/bpf_tracing.h index f4d3e1e2abe2..43ca3aff2292 100644 --- a/tools/lib/bpf/bpf_tracing.h +++ b/tools/lib/bpf/bpf_tracing.h @@ -523,10 +523,17 @@ static __always_inline typeof(name(0)) ____##name(struct pt_regs *ctx, ##args) * Original struct pt_regs * context is preserved as 'ctx' argument. This might * be necessary when using BPF helpers like bpf_perf_event_output(). * - * At the moment BPF_KSYSCALL does not handle all the calling convention - * quirks for mmap(), clone() and compat syscalls transparrently. This may or - * may not change in the future. User needs to take extra measures to handle - * such quirks explicitly, if necessary. + * At the moment BPF_KSYSCALL does not transparently handle all the calling + * convention quirks for the following syscalls: + * + * - mmap(): __ARCH_WANT_SYS_OLD_MMAP. + * - clone(): CONFIG_CLONE_BACKWARDS, CONFIG_CLONE_BACKWARDS2 and + * CONFIG_CLONE_BACKWARDS3. + * - socket-related syscalls: __ARCH_WANT_SYS_SOCKETCALL. + * - compat syscalls. + * + * This may or may not change in the future. User needs to take extra measures + * to handle such quirks explicitly, if necessary. * * This macro relies on BPF CO-RE support and virtual __kconfig externs. */ |