tree: https://git.kernel.org/pub/scm/linux/kernel/git/nsaenz/linux-rpi.git wip head: a6f29192b1e2bf93a6ab7c25c854307431124b8b commit: a6f29192b1e2bf93a6ab7c25c854307431124b8b [5/5] mm/page_alloc: Add remote draining support to per-cpu lists config: arm64-randconfig-s031-20211008 (attached as .config) compiler: aarch64-linux-gcc (GCC) 11.2.0 reproduce: wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # apt-get install sparse # sparse version: v0.6.4-dirty # https://git.kernel.org/pub/scm/linux/kernel/git/nsaenz/linux-rpi.git/comm... git remote add nsaenz-rpi https://git.kernel.org/pub/scm/linux/kernel/git/nsaenz/linux-rpi.git git fetch --no-tags nsaenz-rpi wip git checkout a6f29192b1e2bf93a6ab7c25c854307431124b8b # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=arm64 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 >>) mm/page_alloc.c:1467:30: sparse: sparse: incorrect type in assignment (different modifiers) @@ expected struct list_head *list @@ got struct list_head [noderef] * @@ mm/page_alloc.c:1467:30: sparse: expected struct list_head *list mm/page_alloc.c:1467:30: sparse: got struct list_head [noderef] * mm/page_alloc.c:3183:28: sparse: expected struct pcplists [noderef] *lp mm/page_alloc.c:3183:28: sparse: got struct pcplists [noderef] __rcu * mm/page_alloc.c:3188:36: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct pcplists [noderef] *lp @@ got struct pcplists [noderef] __rcu * @@ mm/page_alloc.c:3188:36: sparse: expected struct pcplists [noderef] *lp mm/page_alloc.c:3188:36: sparse: got struct pcplists [noderef] __rcu * mm/page_alloc.c:3369:40: sparse: sparse: incorrect type in argument 2 (different modifiers) @@ expected struct list_head *head @@ got struct list_head [noderef] * @@ mm/page_alloc.c:3369:40: sparse: expected struct list_head *head mm/page_alloc.c:3369:40: sparse: got struct list_head [noderef] * mm/page_alloc.c:5878:28: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct pcplists [noderef] *lp @@ got struct pcplists [noderef] __rcu * @@ mm/page_alloc.c:5878:28: sparse: expected struct pcplists [noderef] *lp mm/page_alloc.c:5878:28: sparse: got struct pcplists [noderef] __rcu * mm/page_alloc.c:5976:28: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct pcplists [noderef] *lp @@ got struct pcplists [noderef] __rcu * @@ mm/page_alloc.c:5976:28: sparse: expected struct pcplists [noderef] *lp mm/page_alloc.c:5976:28: sparse: got struct pcplists [noderef] __rcu * mm/page_alloc.c:6883:17: sparse: expected struct pcplists [noderef] __rcu *lp mm/page_alloc.c:6883:17: sparse: got struct pcplists [noderef] * mm/page_alloc.c:6887:47: sparse: expected struct list_head *list mm/page_alloc.c:6887:47: sparse: got struct list_head [noderef] __rcu * mm/page_alloc.c:6888:50: sparse: sparse: incorrect type in argument 1 (different modifiers) @@ expected struct list_head *list @@ got struct list_head [noderef] * @@ mm/page_alloc.c:6888:50: sparse: expected struct list_head *list mm/page_alloc.c:6888:50: sparse: got struct list_head [noderef] * mm/page_alloc.c:1452:17: sparse: sparse: dereference of noderef expression mm/page_alloc.c:1507:9: sparse: sparse: dereference of noderef expression mm/page_alloc.c:3095:13: sparse: sparse: dereference of noderef expression mm/page_alloc.c:3096:42: sparse: sparse: dereference of noderef expression mm/page_alloc.c:3184:29: sparse: sparse: dereference of noderef expression mm/page_alloc.c:3189:37: sparse: sparse: dereference of noderef expression mm/page_alloc.c:3223:36: sparse: sparse: dereference of noderef expression mm/page_alloc.c:3370:9: sparse: sparse: dereference of noderef expression mm/page_alloc.c:3372:13: sparse: sparse: dereference of noderef expression mm/page_alloc.c:3604:14: sparse: sparse: incorrect type in assignment (different modifiers) @@ expected struct list_head *list @@ got struct list_head [noderef] * @@ mm/page_alloc.c:3604:14: sparse: expected struct list_head *list mm/page_alloc.c:3604:14: sparse: got struct list_head [noderef] * mm/page_alloc.c:3624:25: sparse: sparse: dereference of noderef expression mm/page_alloc.c:3631:17: sparse: sparse: dereference of noderef expression mm/page_alloc.c: note: in included file (through include/linux/mm.h): include/linux/gfp.h:353:27: sparse: sparse: restricted gfp_t degrades to integer include/linux/gfp.h:353:27: sparse: sparse: restricted gfp_t degrades to integer mm/page_alloc.c:3604:14: sparse: sparse: incorrect type in assignment (different modifiers) @@ expected struct list_head *list @@ got struct list_head [noderef] * @@ mm/page_alloc.c:3604:14: sparse: expected struct list_head *list mm/page_alloc.c:3604:14: sparse: got struct list_head [noderef] * mm/page_alloc.c:3624:25: sparse: sparse: dereference of noderef expression mm/page_alloc.c:3631:17: sparse: sparse: dereference of noderef expression include/linux/gfp.h:353:27: sparse: sparse: restricted gfp_t degrades to integer include/linux/gfp.h:353:27: sparse: sparse: restricted gfp_t degrades to integer include/linux/gfp.h:353:27: sparse: sparse: restricted gfp_t degrades to integer include/linux/gfp.h:353:27: sparse: sparse: restricted gfp_t degrades to integer mm/page_alloc.c:5879:37: sparse: sparse: dereference of noderef expression mm/page_alloc.c:5977:37: sparse: sparse: dereference of noderef expression mm/page_alloc.c:5981:17: sparse: sparse: dereference of noderef expression mm/page_alloc.c:5981:17: sparse: sparse: dereference of noderef expression vim +3183 mm/page_alloc.c 3132 3133 /* 3134 * The implementation of drain_all_pages(), exposing an extra parameter to 3135 * drain on all cpus. 3136 * 3137 * drain_all_pages() is optimized to only execute on cpus where pcplists are 3138 * not empty. The check for non-emptiness can however race with a free to 3139 * pcplist that has not yet increased the lp->count from 0 to 1. Callers 3140 * that need the guarantee that every CPU has drained can disable the 3141 * optimizing racy check. 3142 */ 3143 static void __drain_all_pages(struct zone *zone, bool force_all_cpus) 3144 { 3145 struct per_cpu_pages *pcp; 3146 struct zone *z; 3147 int cpu; 3148 3149 /* 3150 * Allocate in the BSS so we won't require allocation in 3151 * direct reclaim path for CONFIG_CPUMASK_OFFSTACK=y 3152 */ 3153 static cpumask_t cpus_with_pcps; 3154 3155 /* 3156 * Do not drain if one is already in progress unless it's specific to 3157 * a zone. Such callers are primarily CMA and memory hotplug and need 3158 * the drain to be complete when the call returns. 3159 */ 3160 if (unlikely(!mutex_trylock(&pcpu_drain_mutex))) { 3161 if (!zone) 3162 return; 3163 mutex_lock(&pcpu_drain_mutex); 3164 } 3165 3166 /* 3167 * We don't care about racing with CPU hotplug event 3168 * as offline notification will cause the notified 3169 * cpu to drain that CPU pcps and on_each_cpu_mask 3170 * disables preemption as part of its processing 3171 */ 3172 for_each_online_cpu(cpu) { 3173 bool has_pcps = false; 3174 struct pcplists *lp; 3175 3176 if (force_all_cpus) { 3177 /* 3178 * The lp->count check is racy, some callers need a 3179 * guarantee that no cpu is missed. 3180 */ 3181 has_pcps = true; 3182 } else if (zone) { 3184 if (lp->count) 3185 has_pcps = true; 3186 } else { 3187 for_each_populated_zone(z) { 3188 lp = READ_ONCE(per_cpu_ptr(z->per_cpu_pageset, cpu)->lp); 3189 if (lp->count) { 3190 has_pcps = true; 3191 break; 3192 } 3193 } 3194 } 3195 3196 if (has_pcps) 3197 cpumask_set_cpu(cpu, &cpus_with_pcps); 3198 else 3199 cpumask_clear_cpu(cpu, &cpus_with_pcps); 3200 } 3201 3202 if (!force_all_cpus && cpumask_empty(&cpus_with_pcps)) 3203 goto exit; 3204 3205 for_each_cpu(cpu, &cpus_with_pcps) { 3206 for_each_populated_zone(z) { 3207 if (zone && zone != z) 3208 continue; 3209 3210 pcp = per_cpu_ptr(z->per_cpu_pageset, cpu); 3211 pcp->drain = rcu_replace_pointer(pcp->lp, pcp->drain, 3212 mutex_is_locked(&pcpu_drain_mutex)); 3213 } 3214 } 3215 3216 synchronize_rcu_expedited(); 3217 3218 for_each_cpu(cpu, &cpus_with_pcps) { 3219 for_each_populated_zone(z) { 3220 int count; 3221 3222 pcp = per_cpu_ptr(z->per_cpu_pageset, cpu); 3223 count = pcp->drain->count; 3224 if (!count) 3225 continue; 3226 3227 free_pcppages_bulk(z, count, pcp, pcp->drain); 3228 } 3229 } 3230 3231 exit: 3232 mutex_unlock(&pcpu_drain_mutex); 3233 } 3234 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org