tree: https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git arm-kill-set_fs-3 head: a817d8974430d0e8da637c85535ab678d1b19f59 commit: a6d32b05893b32de817f317991435715dc78e16d [34/37] vchiq temp config: x86_64-randconfig-a006-20200917 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 1321160a26e7e489baf9b10d6de90a342f898960) 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 git checkout a6d32b05893b32de817f317991435715dc78e16d # 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 >>): if (ret) ^~~ drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c:867:9: note: initialize the variable 'ret' to silence this warning int ret; ^ = 0 1 warning generated. # https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git/commi... git remote add arnd-playground https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git git fetch --no-tags arnd-playground arm-kill-set_fs-3 git checkout a6d32b05893b32de817f317991435715dc78e16d vim +/ret +904 drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c 860 861 static int vchiq_ioc_dequeue_message(struct vchiq_instance *instance, 862 struct vchiq_dequeue_message *args) 863 { 864 struct user_service *user_service; 865 struct vchiq_service *service; 866 struct vchiq_header *header; 867 int ret; 868 869 DEBUG_INITIALISE(g_state.local) 870 DEBUG_TRACE(DEQUEUE_MESSAGE_LINE); 871 service = find_service_for_instance(instance, args->handle); 872 if (!service) 873 return -EINVAL; 874 875 user_service = (struct user_service *)service->base.userdata; 876 if (user_service->is_vchi == 0) { 877 ret = -EINVAL; 878 goto out; 879 } 880 881 spin_lock(&msg_queue_spinlock); 882 if (user_service->msg_remove == user_service->msg_insert) { 883 if (!args->blocking) { 884 spin_unlock(&msg_queue_spinlock); 885 DEBUG_TRACE(DEQUEUE_MESSAGE_LINE); 886 ret = -EWOULDBLOCK; 887 goto out; 888 } 889 user_service->dequeue_pending = 1; 890 do { 891 spin_unlock(&msg_queue_spinlock); 892 DEBUG_TRACE(DEQUEUE_MESSAGE_LINE); 893 if (wait_for_completion_interruptible( 894 &user_service->insert_event)) { 895 vchiq_log_info(vchiq_arm_log_level, 896 "DEQUEUE_MESSAGE interrupted"); 897 ret = -EINTR; 898 goto out; 899 } 900 spin_lock(&msg_queue_spinlock); 901 } while (user_service->msg_remove == 902 user_service->msg_insert); 903 905 goto out; 906 } 907 908 BUG_ON((int)(user_service->msg_insert - 909 user_service->msg_remove) < 0); 910 911 header = user_service->msg_queue[user_service->msg_remove & 912 (MSG_QUEUE_SIZE - 1)]; 913 user_service->msg_remove++; 914 spin_unlock(&msg_queue_spinlock); 915 916 complete(&user_service->remove_event); 917 if (!header) { 918 ret = -ENOTCONN; 919 } else if (header->size <= args->bufsize) { 920 /* Copy to user space if msgbuf is not NULL */ 921 if (!args->buf || (copy_to_user((void __user *)args->buf, 922 header->data, header->size) == 0)) { 923 ret = header->size; 924 vchiq_release_message(service->handle, header); 925 } else 926 ret = -EFAULT; 927 } else { 928 vchiq_log_error(vchiq_arm_log_level, 929 "header %pK: bufsize %x < size %x", 930 header, args->bufsize, header->size); 931 WARN(1, "invalid size\n"); 932 ret = -EMSGSIZE; 933 } 934 DEBUG_TRACE(DEQUEUE_MESSAGE_LINE); 935 out: 936 unlock_service(service); 937 return ret; 938 } 939 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org