tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git tty-test head: bb57c5de81c6feaad869acce7c38b1049115ac75 commit: bb57c5de81c6feaad869acce7c38b1049115ac75 [9/9] tty: move some internal tty lock enums and functions out of tty.h config: s390-randconfig-r032-20210407 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project c060945b23a1c54d4b2a053ff4b093a2277b303d) 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 s390 cross compiling tool for clang build # apt-get install binutils-s390x-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git/commit/?id=bb57c5de81c6feaad869acce7c38b1049115ac75 git remote add driver-core https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git git fetch --no-tags driver-core tty-test git checkout bb57c5de81c6feaad869acce7c38b1049115ac75 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=s390 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All errors (new ones prefixed by >>): >> drivers/tty/tty_buffer.c:604:40: error: use of undeclared identifier 'TTY_LOCK_SLAVE' lockdep_set_subclass(&port->buf.lock, TTY_LOCK_SLAVE); ^ 1 error generated. -- >> drivers/tty/tty_mutex.c:59:43: error: use of undeclared identifier 'TTY_LOCK_SLAVE' lockdep_set_subclass(&tty->legacy_mutex, TTY_LOCK_SLAVE); ^ 1 error generated. vim +/TTY_LOCK_SLAVE +604 drivers/tty/tty_buffer.c 1d1d14da12e79a Peter Hurley 2015-01-17 600 1d1d14da12e79a Peter Hurley 2015-01-17 601 /* slave ptys can claim nested buffer lock when handling BRK and INTR */ 1d1d14da12e79a Peter Hurley 2015-01-17 602 void tty_buffer_set_lock_subclass(struct tty_port *port) 1d1d14da12e79a Peter Hurley 2015-01-17 603 { 1d1d14da12e79a Peter Hurley 2015-01-17 @604 lockdep_set_subclass(&port->buf.lock, TTY_LOCK_SLAVE); 1d1d14da12e79a Peter Hurley 2015-01-17 605 } e176058f0de53c Peter Hurley 2015-10-17 606 :::::: The code at line 604 was first introduced by commit :::::: 1d1d14da12e79a6c05fbe1a975401f0f56c93316 pty: Fix buffer flush deadlock :::::: TO: Peter Hurley :::::: CC: Greg Kroah-Hartman --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org