Re: [PATCH] tracing: ring-buffer: allowlist clang-generated symbols
"Arnd Bergmann" <[email protected]>
| Newsgroups | dev.linux.lists.llvm,org.kernel.vger.linux-kernel,org.kernel.vger.linux-trace-kernel |
|---|---|
| Message-ID | <[email protected]> |
On Tue, Jul 14, 2026, at 23:56, Steven Rostedt wrote: > On Wed, 17 Jun 2026 14:26:36 +0100 Vincent Donnefort <[email protected]> wrote: > >> On Tue, Jun 16, 2026 at 06:42:03PM +0200, Arnd Bergmann wrote: >> > From: Arnd Bergmann <[email protected]> >> > >> > In randconfig build testing using clang-22, I came across two >> > sets of extra symbols in the ring buffer code that may get >> > inserted by the compiler: >> > >> > Unexpected symbols in kernel/trace/simple_ring_buffer.o: >> > U memset >> > >> > Unexpected symbols in kernel/trace/simple_ring_buffer.o: >> > U llvm_gcda_emit_arcs >> > U llvm_gcda_emit_function >> > U llvm_gcda_end_file >> > U llvm_gcda_start_file >> > U llvm_gcda_summary_info >> > U llvm_gcov_init >> > >> > Add all of these to the allowlist. >> > >> > Signed-off-by: Arnd Bergmann <[email protected]> >> > --- >> > kernel/trace/Makefile | 1 + >> > 1 file changed, 1 insertion(+) >> > >> > diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile >> > index f934ff586bd4..aa8564fb8ff4 100644 >> > --- a/kernel/trace/Makefile >> > +++ b/kernel/trace/Makefile >> > @@ -146,6 +146,7 @@ KASAN_SANITIZE_undefsyms_base.o := y >> >> Would "GCOV_PROFILE_undefsyms_base.o := y" work? > > Arnd? Yes, turning off gcov for this file should avoid the llvm_gcda and llvm_gcov symbols, but not the memset() symbol. All the other features that leave annotations are handled by listing the symbol names (__asan __gcov __kasan __kcsan __hwasan __sancov __sanitizer __tsan __ubsan __msan), so I think for consistency it makes sense to treat llvm gcov the same way we handle gcc gcov and the rest. Arnd