diff options
| author | Nathan Chancellor <nathan@kernel.org> | 2022-11-07 10:07:11 -0700 |
|---|---|---|
| committer | Martin KaFai Lau <martin.lau@kernel.org> | 2022-11-07 16:07:35 -0800 |
| commit | a679120edfcf3d63f066f53afd425d51b480e533 (patch) | |
| tree | 9c566f63cad883bea64a115d0bca0ef0f631ddb5 /kernel | |
| parent | c86df29d11dfba27c0a1f5039cd6fe387fbf4239 (diff) | |
bpf: Add explicit cast to 'void *' for __BPF_DISPATCHER_UPDATE()
When building with clang:
kernel/bpf/dispatcher.c:126:33: error: pointer type mismatch ('void *' and 'unsigned int (*)(const void *, const struct bpf_insn *, bpf_func_t)' (aka 'unsigned int (*)(const void *, const struct bpf_insn *, unsigned int (*)(const void *, const struct bpf_insn *))')) [-Werror,-Wpointer-type-mismatch]
__BPF_DISPATCHER_UPDATE(d, new ?: &bpf_dispatcher_nop_func);
~~~ ^ ~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/bpf.h:1045:54: note: expanded from macro '__BPF_DISPATCHER_UPDATE'
__static_call_update((_d)->sc_key, (_d)->sc_tramp, (_new))
^~~~
1 error generated.
The warning is pointing out that the type of new ('void *') and
&bpf_dispatcher_nop_func are not compatible, which could have side
effects coming out of a conditional operator due to promotion rules.
Add the explicit cast to 'void *' to make it clear that this is
expected, as __BPF_DISPATCHER_UPDATE() expands to a call to
__static_call_update(), which expects a 'void *' as its final argument.
Fixes: c86df29d11df ("bpf: Convert BPF_DISPATCHER to use static_call() (not ftrace)")
Link: https://github.com/ClangBuiltLinux/linux/issues/1755
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: "kernelci.org bot" <bot@kernelci.org>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Björn Töpel <bjorn@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221107170711.42409-1-nathan@kernel.org
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/dispatcher.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/bpf/dispatcher.c b/kernel/bpf/dispatcher.c index 7dfb8d0d5202..c19719f48ce0 100644 --- a/kernel/bpf/dispatcher.c +++ b/kernel/bpf/dispatcher.c @@ -123,7 +123,7 @@ static void bpf_dispatcher_update(struct bpf_dispatcher *d, int prev_num_progs) return; } - __BPF_DISPATCHER_UPDATE(d, new ?: &bpf_dispatcher_nop_func); + __BPF_DISPATCHER_UPDATE(d, new ?: (void *)&bpf_dispatcher_nop_func); if (new) d->image_off = noff; |