TO: Wanpeng Li <wanpengli(a)tencent.com&gt; CC: "Greg Kroah-Hartman" <gregkh(a)linuxfoundation.org&gt; CC: Paolo Bonzini <pbonzini(a)redhat.com&gt; tree: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-4.14.y head: e1f7d50ae3a3ec342e87a9b1ce6787bfb8b3c08b commit: 859cc323167050bcda865415c1716ec9518947f0 [8373/9999] Revert "locking/pvqspinlock: Don't wait if vCPU is preempted" config: x86_64-randconfig-a006-20210620 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project d1baf2895467735ab14f4b3415fce204c0cc8e7f) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install x86_64 cross compiling tool for clang build # apt-get install binutils-x86-64-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.gi... git remote add linux-stable-rc https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git git fetch --no-tags linux-stable-rc linux-4.14.y git checkout 859cc323167050bcda865415c1716ec9518947f0 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): In file included from kernel/locking/qspinlock.c:532: kernel/locking/qspinlock_paravirt.h:470:1: warning: no previous prototype for function '__pv_queued_spin_unlock_slowpath' [-Wmissing-prototypes] __pv_queued_spin_unlock_slowpath(struct qspinlock *lock, u8 locked) ^ kernel/locking/qspinlock_paravirt.h:469:11: note: declare 'static' if the function is not intended to be used outside of this translation unit __visible void ^ static 1 warning generated. kernel/locking/qspinlock.o: warning: objtool: native_queued_spin_lock_slowpath() falls through to next function __pv_queued_spin_unlock_slowpath() --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org