tree: https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git core/softirq head: 63b8d46d609dc61be3e1fe8c46f56b7f2350f6d2 commit: 444494ab87f33eb9582dd3bc54c488b55ed601a2 [7/8] softirq,rcu: Use softirq_needs_break() config: x86_64-randconfig-r021-20200914 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project b2c32c90bab09a6e2c1f370429db26017a182143) 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 444494ab87f33eb9582dd3bc54c488b55ed601a2 # 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 errors (new ones prefixed by >>): In file included from kernel/rcu/tree.c:4458: rcu_do_batch(rdp); ~~~~~~~~~~~~ ^ kernel/rcu/tree.c:2371:13: note: 'rcu_do_batch' declared here static void rcu_do_batch(struct softirq_action *h, struct rcu_data *rdp) ^ 1 error generated. # https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git/commit/?... git remote add peterz-queue https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git git fetch --no-tags peterz-queue core/softirq git checkout 444494ab87f33eb9582dd3bc54c488b55ed601a2 vim +2070 kernel/rcu/tree_plugin.h fbce7497ee5af8 kernel/rcu/tree_plugin.h Paul E. McKenney 2014-06-24 2054 fbce7497ee5af8 kernel/rcu/tree_plugin.h Paul E. McKenney 2014-06-24 2055 /* 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2056 * Invoke any ready callbacks from the corresponding no-CBs CPU, 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2057 * then, if there are no more, wait for more to appear. fbce7497ee5af8 kernel/rcu/tree_plugin.h Paul E. McKenney 2014-06-24 2058 */ 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2059 static void nocb_cb_wait(struct rcu_data *rdp) fbce7497ee5af8 kernel/rcu/tree_plugin.h Paul E. McKenney 2014-06-24 2060 { 1d5a81c18dc68f kernel/rcu/tree_plugin.h Paul E. McKenney 2019-07-15 2061 unsigned long cur_gp_seq; 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2062 unsigned long flags; 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2063 bool needwake_gp = false; 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2064 struct rcu_node *rnp = rdp->mynode; 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2065 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2066 local_irq_save(flags); 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2067 rcu_momentary_dyntick_idle(); 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2068 local_irq_restore(flags); 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2069 local_bh_disable(); 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 @2070 rcu_do_batch(rdp); 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2071 local_bh_enable(); 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2072 lockdep_assert_irqs_enabled(); 81c0b3d724f419 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-28 2073 rcu_nocb_lock_irqsave(rdp, flags); 1d5a81c18dc68f kernel/rcu/tree_plugin.h Paul E. McKenney 2019-07-15 2074 if (rcu_segcblist_nextgp(&rdp->cblist, &cur_gp_seq) && 1d5a81c18dc68f kernel/rcu/tree_plugin.h Paul E. McKenney 2019-07-15 2075 rcu_seq_done(&rnp->gp_seq, cur_gp_seq) && 1d5a81c18dc68f kernel/rcu/tree_plugin.h Paul E. McKenney 2019-07-15 2076 raw_spin_trylock_rcu_node(rnp)) { /* irqs already disabled. */ 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2077 needwake_gp = rcu_advance_cbs(rdp->mynode, rdp); 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2078 raw_spin_unlock_rcu_node(rnp); /* irqs remain disabled. */ 523bddd553c09a kernel/rcu/tree_plugin.h Paul E. McKenney 2019-06-01 2079 } 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2080 if (rcu_segcblist_ready_cbs(&rdp->cblist)) { 81c0b3d724f419 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-28 2081 rcu_nocb_unlock_irqrestore(rdp, flags); 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2082 if (needwake_gp) 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2083 rcu_gp_kthread_wake(); 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2084 return; 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2085 } 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2086 f7c9a9b664fb32 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-04-01 2087 trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("CBSleep")); 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2088 WRITE_ONCE(rdp->nocb_cb_sleep, true); 81c0b3d724f419 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-28 2089 rcu_nocb_unlock_irqrestore(rdp, flags); 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2090 if (needwake_gp) 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2091 rcu_gp_kthread_wake(); 12f54c3a841010 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-03-29 2092 swait_event_interruptible_exclusive(rdp->nocb_cb_wq, 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2093 !READ_ONCE(rdp->nocb_cb_sleep)); 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2094 if (!smp_load_acquire(&rdp->nocb_cb_sleep)) { /* VVV */ 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2095 /* ^^^ Ensure CB invocation follows _sleep test. */ 5d6742b37727e1 kernel/rcu/tree_plugin.h Paul E. McKenney 2019-05-15 2096 return; 69a79bb12a8102 kernel/rcutree_plugin.h Paul E. McKenney 2013-08-15 2097 } 73a860cd58a1eb kernel/rcu/tree_plugin.h Paul E. McKenney 2014-08-14 2098 WARN_ON(signal_pending(current)); 88d1bead858d88 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-07-04 2099 trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("WokeEmpty")); 3fbfbf7a3b66ec kernel/rcutree_plugin.h Paul E. McKenney 2012-08-19 2100 } 3fbfbf7a3b66ec kernel/rcutree_plugin.h Paul E. McKenney 2012-08-19 2101 :::::: The code at line 2070 was first introduced by commit :::::: 5d6742b37727e111f4755155e59c5319cf5caa7b rcu/nocb: Use rcu_segcblist for no-CBs CPUs :::::: TO: Paul E. McKenney <paulmck(a)linux.ibm.com&gt; :::::: CC: Paul E. McKenney <paulmck(a)linux.ibm.com&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org