Hi "Joel, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on linus/master] [also build test WARNING on v5.19-rc3 next-20220622] [cannot apply to paulmck-rcu/dev] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/intel-lab-lkp/linux/commits/Joel-Fernandes-Google/Implement-call_rcu_lazy-and-miscellaneous-fixes/20220623-065447 base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git de5c208d533a46a074eb46ea17f672cc005a7269 config: riscv-nommu_k210_defconfig (https://download.01.org/0day-ci/archive/20220623/202206230916.2YtpR3sO-lkp@xxxxxxxxx/config) compiler: riscv64-linux-gcc (GCC) 11.3.0 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://github.com/intel-lab-lkp/linux/commit/543ee31928d1cff057320ff64603283a34fe0052 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Joel-Fernandes-Google/Implement-call_rcu_lazy-and-miscellaneous-fixes/20220623-065447 git checkout 543ee31928d1cff057320ff64603283a34fe0052 # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.3.0 make.cross W=1 O=build_dir ARCH=riscv SHELL=/bin/bash kernel/rcu/ If you fix the issue, kindly add following tag where applicable Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): kernel/rcu/tree.c:3103: warning: Function parameter or member 'lazy' not described in '__call_rcu_common' >> kernel/rcu/tree.c:3103: warning: expecting prototype for call_rcu(). Prototype was for __call_rcu_common() instead vim +3103 kernel/rcu/tree.c b2b00ddf193bf83 kernel/rcu/tree.c Paul E. McKenney 2019-10-30 3060 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3061 /** 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3062 * call_rcu() - Queue an RCU callback for invocation after a grace period. 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3063 * @head: structure to be used for queueing the RCU updates. 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3064 * @func: actual callback function to be invoked after the grace period 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3065 * 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3066 * The callback function will be invoked some time after a full grace 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3067 * period elapses, in other words after all pre-existing RCU read-side 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3068 * critical sections have completed. However, the callback function 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3069 * might well execute concurrently with RCU read-side critical sections 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3070 * that started after call_rcu() was invoked. 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3071 * 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3072 * RCU read-side critical sections are delimited by rcu_read_lock() 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3073 * and rcu_read_unlock(), and may be nested. In addition, but only in 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3074 * v5.0 and later, regions of code across which interrupts, preemption, 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3075 * or softirqs have been disabled also serve as RCU read-side critical 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3076 * sections. This includes hardware interrupt handlers, softirq handlers, 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3077 * and NMI handlers. 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3078 * 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3079 * Note that all CPUs must agree that the grace period extended beyond 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3080 * all pre-existing RCU read-side critical section. On systems with more 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3081 * than one CPU, this means that when "func()" is invoked, each CPU is 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3082 * guaranteed to have executed a full memory barrier since the end of its 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3083 * last RCU read-side critical section whose beginning preceded the call 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3084 * to call_rcu(). It also means that each CPU executing an RCU read-side 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3085 * critical section that continues beyond the start of "func()" must have 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3086 * executed a memory barrier after the call_rcu() but before the beginning 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3087 * of that RCU read-side critical section. Note that these guarantees 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3088 * include CPUs that are offline, idle, or executing in user mode, as 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3089 * well as CPUs that are executing in the kernel. 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3090 * 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3091 * Furthermore, if CPU A invoked call_rcu() and CPU B invoked the 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3092 * resulting RCU callback function "func()", then both CPU A and CPU B are 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3093 * guaranteed to execute a full memory barrier during the time interval 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3094 * between the call to call_rcu() and the invocation of "func()" -- even 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3095 * if CPU A and CPU B are the same CPU (but again only if the system has 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3096 * more than one CPU). 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3097 * 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3098 * Implementation of these memory-ordering guarantees is described here: 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3099 * Documentation/RCU/Design/Memory-Ordering/Tree-RCU-Memory-Ordering.rst. 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3100 */ 543ee31928d1cff kernel/rcu/tree.c Joel Fernandes (Google 2022-06-22 3101) static void 543ee31928d1cff kernel/rcu/tree.c Joel Fernandes (Google 2022-06-22 3102) __call_rcu_common(struct rcu_head *head, rcu_callback_t func, bool lazy) 64db4cfff99c04c kernel/rcutree.c Paul E. McKenney 2008-12-18 @3103 { b4b7914a6a73fc1 kernel/rcu/tree.c Paul E. McKenney 2020-12-08 3104 static atomic_t doublefrees; 64db4cfff99c04c kernel/rcutree.c Paul E. McKenney 2008-12-18 3105 unsigned long flags; 64db4cfff99c04c kernel/rcutree.c Paul E. McKenney 2008-12-18 3106 struct rcu_data *rdp; 5d6742b37727e11 kernel/rcu/tree.c Paul E. McKenney 2019-05-15 3107 bool was_alldone; 64db4cfff99c04c kernel/rcutree.c Paul E. McKenney 2008-12-18 3108 b8f2ed538477d9a kernel/rcu/tree.c Paul E. McKenney 2016-08-23 3109 /* Misaligned rcu_head! */ b8f2ed538477d9a kernel/rcu/tree.c Paul E. McKenney 2016-08-23 3110 WARN_ON_ONCE((unsigned long)head & (sizeof(void *) - 1)); b8f2ed538477d9a kernel/rcu/tree.c Paul E. McKenney 2016-08-23 3111 ae15018456c44b7 kernel/rcutree.c Paul E. McKenney 2013-04-23 3112 if (debug_rcu_head_queue(head)) { fa3c66476975abf kernel/rcu/tree.c Paul E. McKenney 2017-05-03 3113 /* fa3c66476975abf kernel/rcu/tree.c Paul E. McKenney 2017-05-03 3114 * Probable double call_rcu(), so leak the callback. fa3c66476975abf kernel/rcu/tree.c Paul E. McKenney 2017-05-03 3115 * Use rcu:rcu_callback trace event to find the previous 1fe09ebe7a9c990 kernel/rcu/tree.c Paul E. McKenney 2021-12-18 3116 * time callback was passed to call_rcu(). fa3c66476975abf kernel/rcu/tree.c Paul E. McKenney 2017-05-03 3117 */ b4b7914a6a73fc1 kernel/rcu/tree.c Paul E. McKenney 2020-12-08 3118 if (atomic_inc_return(&doublefrees) < 4) { b4b7914a6a73fc1 kernel/rcu/tree.c Paul E. McKenney 2020-12-08 3119 pr_err("%s(): Double-freed CB %p->%pS()!!! ", __func__, head, head->func); b4b7914a6a73fc1 kernel/rcu/tree.c Paul E. McKenney 2020-12-08 3120 mem_dump_obj(head); b4b7914a6a73fc1 kernel/rcu/tree.c Paul E. McKenney 2020-12-08 3121 } 7d0ae8086b82831 kernel/rcu/tree.c Paul E. McKenney 2015-03-03 3122 WRITE_ONCE(head->func, rcu_leak_callback); ae15018456c44b7 kernel/rcutree.c Paul E. McKenney 2013-04-23 3123 return; ae15018456c44b7 kernel/rcutree.c Paul E. McKenney 2013-04-23 3124 } 64db4cfff99c04c kernel/rcutree.c Paul E. McKenney 2008-12-18 3125 head->func = func; 64db4cfff99c04c kernel/rcutree.c Paul E. McKenney 2008-12-18 3126 head->next = NULL; 300c0c5e721834f kernel/rcu/tree.c Jun Miao 2021-11-16 3127 kasan_record_aux_stack_noalloc(head); d818cc76e2b4d5f kernel/rcu/tree.c Zqiang 2021-12-26 3128 local_irq_save(flags); da1df50d16171f4 kernel/rcu/tree.c Paul E. McKenney 2018-07-03 3129 rdp = this_cpu_ptr(&rcu_data); 64db4cfff99c04c kernel/rcutree.c Paul E. McKenney 2008-12-18 3130 64db4cfff99c04c kernel/rcutree.c Paul E. McKenney 2008-12-18 3131 /* Add the callback to our list. */ 5d6742b37727e11 kernel/rcu/tree.c Paul E. McKenney 2019-05-15 3132 if (unlikely(!rcu_segcblist_is_enabled(&rdp->cblist))) { 5d6742b37727e11 kernel/rcu/tree.c Paul E. McKenney 2019-05-15 3133 // This can trigger due to call_rcu() from offline CPU: 5d6742b37727e11 kernel/rcu/tree.c Paul E. McKenney 2019-05-15 3134 WARN_ON_ONCE(rcu_scheduler_active != RCU_SCHEDULER_INACTIVE); 34404ca8fb252cc kernel/rcu/tree.c Paul E. McKenney 2015-01-19 3135 WARN_ON_ONCE(!rcu_is_watching()); 5d6742b37727e11 kernel/rcu/tree.c Paul E. McKenney 2019-05-15 3136 // Very early boot, before rcu_init(). Initialize if needed 5d6742b37727e11 kernel/rcu/tree.c Paul E. McKenney 2019-05-15 3137 // and then drop through to queue the callback. 15fecf89e46a962 kernel/rcu/tree.c Paul E. McKenney 2017-02-08 3138 if (rcu_segcblist_empty(&rdp->cblist)) 15fecf89e46a962 kernel/rcu/tree.c Paul E. McKenney 2017-02-08 3139 rcu_segcblist_init(&rdp->cblist); 143da9c2fc030a5 kernel/rcu/tree.c Paul E. McKenney 2015-01-19 3140 } 77a40f97030b27b kernel/rcu/tree.c Joel Fernandes (Google 2019-08-30 3141) b2b00ddf193bf83 kernel/rcu/tree.c Paul E. McKenney 2019-10-30 3142 check_cb_ovld(rdp); 543ee31928d1cff kernel/rcu/tree.c Joel Fernandes (Google 2022-06-22 3143) if (rcu_nocb_try_bypass(rdp, head, &was_alldone, flags, lazy)) d1b222c6be1f8bf kernel/rcu/tree.c Paul E. McKenney 2019-07-02 3144 return; // Enqueued onto ->nocb_bypass, so just leave. b692dc4adfcff54 kernel/rcu/tree.c Paul E. McKenney 2020-02-11 3145 // If no-CBs CPU gets here, rcu_nocb_try_bypass() acquired ->nocb_lock. 77a40f97030b27b kernel/rcu/tree.c Joel Fernandes (Google 2019-08-30 3146) rcu_segcblist_enqueue(&rdp->cblist, head); c408b215f58f715 kernel/rcu/tree.c Uladzislau Rezki (Sony 2020-05-25 3147) if (__is_kvfree_rcu_offset((unsigned long)func)) c408b215f58f715 kernel/rcu/tree.c Uladzislau Rezki (Sony 2020-05-25 3148) trace_rcu_kvfree_callback(rcu_state.name, head, 3c779dfef2c4524 kernel/rcu/tree.c Paul E. McKenney 2018-07-05 3149 (unsigned long)func, 15fecf89e46a962 kernel/rcu/tree.c Paul E. McKenney 2017-02-08 3150 rcu_segcblist_n_cbs(&rdp->cblist)); d4c08f2ac311a36 kernel/rcutree.c Paul E. McKenney 2011-06-25 3151 else 3c779dfef2c4524 kernel/rcu/tree.c Paul E. McKenney 2018-07-05 3152 trace_rcu_callback(rcu_state.name, head, 15fecf89e46a962 kernel/rcu/tree.c Paul E. McKenney 2017-02-08 3153 rcu_segcblist_n_cbs(&rdp->cblist)); d4c08f2ac311a36 kernel/rcutree.c Paul E. McKenney 2011-06-25 3154 3afe7fa535491ec kernel/rcu/tree.c Joel Fernandes (Google 2020-11-14 3155) trace_rcu_segcb_stats(&rdp->cblist, TPS("SegCBQueued")); 3afe7fa535491ec kernel/rcu/tree.c Joel Fernandes (Google 2020-11-14 3156) 29154c57e35a191 kernel/rcutree.c Paul E. McKenney 2012-05-30 3157 /* Go handle any RCU core processing required. */ 3820b513a2e33d6 kernel/rcu/tree.c Frederic Weisbecker 2020-11-12 3158 if (unlikely(rcu_rdp_is_offloaded(rdp))) { 5d6742b37727e11 kernel/rcu/tree.c Paul E. McKenney 2019-05-15 3159 __call_rcu_nocb_wake(rdp, was_alldone, flags); /* unlocks */ 5d6742b37727e11 kernel/rcu/tree.c Paul E. McKenney 2019-05-15 3160 } else { 5c7d89676bc5196 kernel/rcu/tree.c Paul E. McKenney 2018-07-03 3161 __call_rcu_core(rdp, head, flags); 64db4cfff99c04c kernel/rcutree.c Paul E. McKenney 2008-12-18 3162 local_irq_restore(flags); 64db4cfff99c04c kernel/rcutree.c Paul E. McKenney 2008-12-18 3163 } 5d6742b37727e11 kernel/rcu/tree.c Paul E. McKenney 2019-05-15 3164 } 64db4cfff99c04c kernel/rcutree.c Paul E. McKenney 2008-12-18 3165 -- 0-DAY CI Kernel Test Service https://01.org/lkp
