Hi all, I failed to make bpf selftest testcases based on the upstream master branch. And I need help to fix it. After installing the new kernel and modules, I have tried following commands to build bpf testcases: " cd ~/dev/linux/tools/testing/selftests/bpf make " Then error message shows up as follows: " INSTALL bpftool GEN vmlinux.h CLNG-BPF [test_maps] btf__core_reloc_primitives___err_non_ptr.o CLNG-BPF [test_maps] test_global_data.o CLNG-BPF [test_maps] test_global_func8.o CLNG-BPF [test_maps] test_ksyms_btf_null_check.o CLNG-BPF [test_maps] linked_funcs2.o CLNG-BPF [test_maps] bpf_iter_test_kern5.o CLNG-BPF [test_maps] test_static_linked2.o CLNG-BPF [test_maps] test_global_func13.o CLNG-BPF [test_maps] test_cls_redirect_subprogs.o CLNG-BPF [test_maps] test_core_reloc_nesting.o CLNG-BPF [test_maps] tailcall_bpf2bpf1.o CLNG-BPF [test_maps] test_endian.o CLNG-BPF [test_maps] test_cls_redirect.o CLNG-BPF [test_maps] btf__core_reloc_type_based___incompat.o CLNG-BPF [test_maps] test_btf_newkv.o CLNG-BPF [test_maps] pyperf600.o CLNG-BPF [test_maps] test_btf_nokv.o CLNG-BPF [test_maps] atomics.o fatal error: error in backend: line 27: Invalid usage of the XADD return value PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backtrace, preprocessed source, and associated run script. Stack dump: 0. Program arguments: clang -g -D__TARGET_ARCH_x86 -mlittle-endian -I/root/dev/linux/tools/testing/selftests/bpf/tools/include -I/root/dev/linux/tools/testing/selftests/bpf -I/root/dev/linux/tools/include/uapi -I/root/dev/linux/tools/testing/selftests/usr/include -idirafter /usr/local/include -idirafter /usr/lib/llvm-11/lib/clang/11.1.0/include -idirafter /usr/include/x86_64-linux-gnu -idirafter /usr/include -Wno-compare-distinct-pointer-types -DENABLE_ATOMICS_TESTS -O2 -target bpf -c progs/atomics.c -o /root/dev/linux/tools/testing/selftests/bpf/atomics.o -mcpu=v3 1. <eof> parser at end of file 2. Code generation 3. Running pass 'Function Pass Manager' on module 'progs/atomics.c'. 4. Running pass 'BPF PreEmit Checking' on function '@add' #0 0x00007f81ec29ee8f llvm::sys::PrintStackTrace(llvm::raw_ostream&) (/lib/x86_64-linux-gnu/libLLVM-11.so.1+0xbbae8f) #1 0x00007f81ec29d200 llvm::sys::RunSignalHandlers() (/lib/x86_64-linux-gnu/libLLVM-11.so.1+0xbb9200) #2 0x00007f81ec29e5dd llvm::sys::CleanupOnSignal(unsigned long) (/lib/x86_64-linux-gnu/libLLVM-11.so.1+0xbba5dd) #3 0x00007f81ec1e6d2a (/lib/x86_64-linux-gnu/libLLVM-11.so.1+0xb02d2a) #4 0x00007f81ec1e6ccb (/lib/x86_64-linux-gnu/libLLVM-11.so.1+0xb02ccb) #5 0x00007f81ec299d4e (/lib/x86_64-linux-gnu/libLLVM-11.so.1+0xbb5d4e) #6 0x00000000004134f2 (/usr/lib/llvm-11/bin/clang+0x4134f2) #7 0x00007f81ec1f2d4f llvm::report_fatal_error(llvm::Twine const&, bool) (/lib/x86_64-linux-gnu/libLLVM-11.so.1+0xb0ed4f) #8 0x00007f81ec1f2e27 (/lib/x86_64-linux-gnu/libLLVM-11.so.1+0xb0ee27) #9 0x00007f81edd55595 (/lib/x86_64-linux-gnu/libLLVM-11.so.1+0x2671595) #10 0x00007f81ec57339e llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (/lib/x86_64-linux-gnu/libLLVM-11.so.1+0xe8f39e) #11 0x00007f81ec3ae889 llvm::FPPassManager::runOnFunction(llvm::Function&) (/lib/x86_64-linux-gnu/libLLVM-11.so.1+0xcca889) #12 0x00007f81ec3b3eb3 llvm::FPPassManager::runOnModule(llvm::Module&) (/lib/x86_64-linux-gnu/libLLVM-11.so.1+0xccfeb3) #13 0x00007f81ec3aeea0 llvm::legacy::PassManagerImpl::run(llvm::Module&) (/lib/x86_64-linux-gnu/libLLVM-11.so.1+0xccaea0) #14 0x00007f81ea068e96 clang::EmitBackendOutput(clang::DiagnosticsEngine&, clang::HeaderSearchOptions const&, clang::CodeGenOptions const&, clang::TargetOptions const&, clang::LangOptions const&, llvm::DataLayout const&, llvm::Module*, clang::BackendAction, std::unique_ptr<llvm::raw_pwrite_stream, std::default_delete<llvm::raw_pwrite_stream> >) (/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x164de96) #15 0x00007f81ea329a36 (/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x190ea36) #16 0x00007f81e93e9093 clang::ParseAST(clang::Sema&, bool, bool) (/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x9ce093) #17 0x00007f81ea9c9c38 clang::FrontendAction::Execute() (/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x1faec38) #18 0x00007f81ea97ff11 clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x1f64f11) #19 0x00007f81eaa2f6b0 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x20146b0) #20 0x00000000004131bf cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/usr/lib/llvm-11/bin/clang+0x4131bf) #21 0x00000000004115fe (/usr/lib/llvm-11/bin/clang+0x4115fe) #22 0x00007f81ea6a9a02 (/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x1c8ea02) #23 0x00007f81ec1e6cad llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) (/lib/x86_64-linux-gnu/libLLVM-11.so.1+0xb02cad) #24 0x00007f81ea6a8f2f clang::driver::CC1Command::Execute(llvm::ArrayRef<llvm::Optional<llvm::StringRef> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >*, bool*) const (/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x1c8df2f) #25 0x00007f81ea680d5f clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&) const (/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x1c65d5f) #26 0x00007f81ea680f07 clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*> >&) const (/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x1c65f07) #27 0x00007f81ea694a7c clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*> >&) (/lib/x86_64-linux-gnu/libclang-cpp.so.11+0x1c79a7c) #28 0x00000000004110a3 main (/usr/lib/llvm-11/bin/clang+0x4110a3) #29 0x00007f81e855b09b __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409b) #30 0x000000000040e89a _start (/usr/lib/llvm-11/bin/clang+0x40e89a) make: *** [Makefile:470: /root/dev/linux/tools/testing/selftests/bpf/atomics.o] Error 1 " I am using a virtual machine with 8 cpus. The kernel and clang version are: " kernel: 5.14.0-rc3.bm.1-amd64 #4 SMP Sun Aug 1 23:28:24 CST 2021 x86_64 GNU/Linux clang: Debian clang version 11.1.0-++20210622113218+1fdec59bffc1-1~exp1~20210622213839.163 "
