[paulmck-rcu:dev.2023.04.26a 35/51] arch/powerpc/kernel/smp.c:1768:1: error: function declared 'noreturn' should not return

[kernel test robot <lkp@intel.com>]

Hi Josh,

FYI, the error/warning still remains.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git dev.2023.04.26a
head:   56b38a90a12f76e463a7381d8cff854926fa2b59
commit: 2b927bfdda366c1719e021cd0e9688baf933c9cf [35/51] objtool: Fix for unreachable instruction warning
config: powerpc-buildonly-randconfig-r003-20230427 (https://download.01.org/0day-ci/archive/20230427/202304271416.DjRKPeoJ-lkp@intel.com/config)
compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project 437b7602e4a998220871de78afcb020b9c14a661)
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 powerpc cross compiling tool for clang build
        # apt-get install binutils-powerpc-linux-gnu
        # https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git/commit/?id=2b927bfdda366c1719e021cd0e9688baf933c9cf
        git remote add paulmck-rcu https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git
        git fetch --no-tags paulmck-rcu dev.2023.04.26a
        git checkout 2b927bfdda366c1719e021cd0e9688baf933c9cf
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=powerpc olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash arch/powerpc/kernel/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202304271416.DjRKPeoJ-lkp@intel.com/

All errors (new ones prefixed by >>):

>> arch/powerpc/kernel/smp.c:1768:1: error: function declared 'noreturn' should not return [-Werror,-Winvalid-noreturn]
   }
   ^
   1 error generated.

Kconfig warnings: (for reference only)
   WARNING: unmet direct dependencies detected for HOTPLUG_CPU
   Depends on [n]: SMP [=y] && (PPC_PSERIES [=n] || PPC_PMAC [=n] || PPC_POWERNV [=n] || FSL_SOC_BOOKE [=n])
   Selected by [y]:
   - PM_SLEEP_SMP [=y] && SMP [=y] && (ARCH_SUSPEND_POSSIBLE [=y] || ARCH_HIBERNATION_POSSIBLE [=y]) && PM_SLEEP [=y]


vim +/noreturn +1768 arch/powerpc/kernel/smp.c

d0174c721900ff Nathan Fontenot        2010-01-14  1754  
1ea21ba231f248 Michael Ellerman       2020-08-19  1755  void arch_cpu_idle_dead(void)
1ea21ba231f248 Michael Ellerman       2020-08-19  1756  {
424ef0160f439f Naveen N. Rao          2018-04-19  1757  	/*
424ef0160f439f Naveen N. Rao          2018-04-19  1758  	 * Disable on the down path. This will be re-enabled by
424ef0160f439f Naveen N. Rao          2018-04-19  1759  	 * start_secondary() via start_secondary_resume() below
424ef0160f439f Naveen N. Rao          2018-04-19  1760  	 */
424ef0160f439f Naveen N. Rao          2018-04-19  1761  	this_cpu_disable_ftrace();
424ef0160f439f Naveen N. Rao          2018-04-19  1762  
39f87561454dc3 Michael Ellerman       2020-08-19  1763  	if (smp_ops->cpu_offline_self)
39f87561454dc3 Michael Ellerman       2020-08-19  1764  		smp_ops->cpu_offline_self();
fa3f82c8bb7acb Benjamin Herrenschmidt 2011-02-10  1765  
fa3f82c8bb7acb Benjamin Herrenschmidt 2011-02-10  1766  	/* If we return, we re-enter start_secondary */
fa3f82c8bb7acb Benjamin Herrenschmidt 2011-02-10  1767  	start_secondary_resume();
abb17f9c3a92c5 Milton Miller          2010-05-19 @1768  }
fa3f82c8bb7acb Benjamin Herrenschmidt 2011-02-10  1769  

:::::: The code at line 1768 was first introduced by commit
:::::: abb17f9c3a92c5acf30e749efdf0419b7f50a5b8 powerpc: Use common cpu_die (fixes SMP+SUSPEND build)

:::::: TO: Milton Miller <miltonm@bga.com>
:::::: CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests