tree: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git sched/core head: d74f87f37672e71457bfcc14eca5eeb1d61b6438 commit: c89970202a1153b2fc230e89f90c180bd5bcbcef [28/28] cputime: remove cputime_to_nsecs fallback config: ia64-randconfig-r011-20230111 compiler: ia64-linux-gcc (GCC) 12.1.0 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 # https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=c89970202a1153b2fc230e89f90c180bd5bcbcef git remote add tip https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git git fetch --no-tags tip sched/core git checkout c89970202a1153b2fc230e89f90c180bd5bcbcef # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=ia64 olddefconfig COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=ia64 SHELL=/bin/bash arch/ia64/kernel/ If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot All warnings (new ones prefixed by >>): >> arch/ia64/kernel/time.c:110:6: warning: no previous prototype for 'arch_vtime_task_switch' [-Wmissing-prototypes] 110 | void arch_vtime_task_switch(struct task_struct *prev) | ^~~~~~~~~~~~~~~~~~~~~~ arch/ia64/kernel/time.c:259:6: warning: no previous prototype for 'ia64_init_itm' [-Wmissing-prototypes] 259 | void ia64_init_itm(void) | ^~~~~~~~~~~~~ arch/ia64/kernel/time.c:396:1: warning: no previous prototype for 'time_init' [-Wmissing-prototypes] 396 | time_init (void) | ^~~~~~~~~ vim +/arch_vtime_task_switch +110 arch/ia64/kernel/time.c 5bf412cd769eb5 Frederic Weisbecker 2012-09-08 104 b64f34cdfe5bef Hidetoshi Seto 2008-01-29 105 /* b64f34cdfe5bef Hidetoshi Seto 2008-01-29 106 * Called from the context switch with interrupts disabled, to charge all b64f34cdfe5bef Hidetoshi Seto 2008-01-29 107 * accumulated times to the current process, and to prepare accounting on b64f34cdfe5bef Hidetoshi Seto 2008-01-29 108 * the next process. b64f34cdfe5bef Hidetoshi Seto 2008-01-29 109 */ e3942ba0405236 Frederic Weisbecker 2012-11-14 @110 void arch_vtime_task_switch(struct task_struct *prev) b64f34cdfe5bef Hidetoshi Seto 2008-01-29 111 { b64f34cdfe5bef Hidetoshi Seto 2008-01-29 112 struct thread_info *pi = task_thread_info(prev); baa36046d09ea6 Frederic Weisbecker 2012-06-18 113 struct thread_info *ni = task_thread_info(current); b64f34cdfe5bef Hidetoshi Seto 2008-01-29 114 8388d21468e7e7 Frederic Weisbecker 2017-01-05 115 ni->ac_stamp = pi->ac_stamp; b64f34cdfe5bef Hidetoshi Seto 2008-01-29 116 ni->ac_stime = ni->ac_utime = 0; b64f34cdfe5bef Hidetoshi Seto 2008-01-29 117 } b64f34cdfe5bef Hidetoshi Seto 2008-01-29 118 :::::: The code at line 110 was first introduced by commit :::::: e3942ba04052364d3c6454103362cafd87456010 vtime: Consolidate a bit the ctx switch code :::::: TO: Frederic Weisbecker :::::: CC: Frederic Weisbecker -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests