tree: https://git.kernel.org/pub/scm/linux/kernel/git/jfern/linux.git rcu-segcb head: fb866e723f8f64bc4f1e6d19add6a4ff285fcc02 commit: 6c20fe430956a44bc2034f58d55678fb8e8cff19 [3/7] rcu/trace: Add name of the source for gp_seq config: x86_64-randconfig-s021-20200618 (attached as .config) compiler: gcc-9 (Debian 9.3.0-13) 9.3.0 reproduce: # apt-get install sparse # sparse version: v0.6.2-rc1-10-gc17b1b06-dirty git checkout 6c20fe430956a44bc2034f58d55678fb8e8cff19 # save the attached .config to linux build tree make W=1 C=1 ARCH=x86_64 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; sparse warnings: (new ones prefixed by >>) kernel/rcu/tree.c:1279:13: sparse: sparse: context imbalance in 'rcu_start_this_gp' - different lock contexts for basic block kernel/rcu/tree.c:1733:9: sparse: sparse: context imbalance in 'rcu_gp_init' - different lock contexts for basic block kernel/rcu/tree.c:2495:9: sparse: sparse: context imbalance in 'force_qs_rnp' - different lock contexts for basic block kernel/rcu/tree.c:2549:25: sparse: sparse: context imbalance in 'rcu_force_quiescent_state' - unexpected unlock arch/x86/include/asm/paravirt.h:765:9: sparse: sparse: context imbalance in 'kfree_call_rcu' - different lock contexts for basic block kernel/rcu/tree_exp.h:189:9: sparse: sparse: context imbalance in '__rcu_report_exp_rnp' - different lock contexts for basic block vim +792 kernel/rcu/tree_plugin.h f41d911f8c49a5 kernel/rcutree_plugin.h Paul E. McKenney 2009-08-22 779 45975c7d21a1c0 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-07-02 780 /* 90326f0521a880 kernel/rcu/tree_plugin.h Sebastian Andrzej Siewior 2019-10-15 781 * Note a quiescent state for PREEMPTION=n. Because we do not need to know 45975c7d21a1c0 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-07-02 782 * how many quiescent states passed, just if there was at least one since 45975c7d21a1c0 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-07-02 783 * the start of the grace period, this just sets a flag. The caller must 45975c7d21a1c0 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-07-02 784 * have disabled preemption. 45975c7d21a1c0 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-07-02 785 */ 45975c7d21a1c0 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-07-02 786 static void rcu_qs(void) d28139c4e96713 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-06-28 787 { 45975c7d21a1c0 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-07-02 788 RCU_LOCKDEP_WARN(preemptible(), "rcu_qs() invoked with preemption enabled!!!"); 45975c7d21a1c0 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-07-02 789 if (!__this_cpu_read(rcu_data.cpu_no_qs.s)) 45975c7d21a1c0 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-07-02 790 return; 45975c7d21a1c0 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-07-02 @791 trace_rcu_grace_period(TPS("rcu_sched"), 45975c7d21a1c0 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-07-02 @792 __this_cpu_read(rcu_data.gp_seq), TPS("cpuqs")); 45975c7d21a1c0 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-07-02 793 __this_cpu_write(rcu_data.cpu_no_qs.b.norm, false); 45975c7d21a1c0 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-07-02 794 if (!__this_cpu_read(rcu_data.cpu_no_qs.b.exp)) 45975c7d21a1c0 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-07-02 795 return; 45975c7d21a1c0 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-07-02 796 __this_cpu_write(rcu_data.cpu_no_qs.b.exp, false); 63d4c8c97948b0 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-07-03 797 rcu_report_exp_rdp(this_cpu_ptr(&rcu_data)); d28139c4e96713 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-06-28 798 } d28139c4e96713 kernel/rcu/tree_plugin.h Paul E. McKenney 2018-06-28 799 :::::: The code at line 792 was first introduced by commit :::::: 45975c7d21a1c0aba97e3d8007e2a7c123145748 rcu: Define RCU-sched API in terms of RCU for Tree RCU PREEMPT builds :::::: TO: Paul E. McKenney <paulmck(a)linux.vnet.ibm.com&gt; :::::: CC: Paul E. McKenney <paulmck(a)linux.vnet.ibm.com&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org