tree: https://github.com/0day-ci/linux/commits/UPDATE-20220111-073805/trondmy-k... head: f1c8b8b2e616895aa0f5be4e53d4cd1ffa751001 commit: f1c8b8b2e616895aa0f5be4e53d4cd1ffa751001 iomap: Address soft lockup in iomap_finish_ioend() date: 54 minutes ago config: um-i386_defconfig (https://download.01.org/0day-ci/archive/20220111/202201110815.jsASX6ar-lk...) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce (this is a W=1 build): # https://github.com/0day-ci/linux/commit/f1c8b8b2e616895aa0f5be4e53d4cd1ff... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review UPDATE-20220111-073805/trondmy-kernel-org/iomap-Address-soft-lockup-in-iomap_finish_ioend/20211231-034313 git checkout f1c8b8b2e616895aa0f5be4e53d4cd1ffa751001 # save the config file to linux build tree mkdir build_dir make W=1 O=build_dir ARCH=um SUBARCH=i386 SHELL=/bin/bash fs/iomap/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): fs/iomap/buffered-io.c: In function 'iomap_finish_ioends': 1093 | trace_printk("pages %u, start sector 0x%llx size %lu pcnt %u", | ~~^ | | | long unsigned int | %u ...... 1096 | ioend->io_size, | ~~~~~~~~~~~~~~ | | | size_t {aka unsigned int} fs/iomap/buffered-io.c:1106:53: warning: format '%lu' expects argument of type 'long unsigned int', but argument 4 has type 'size_t' {aka 'unsigned int'} [-Wformat=] 1106 | trace_printk("pages %u, start sector 0x%llx size %lu pcnt %u", | ~~^ | | | long unsigned int | %u ...... 1109 | ioend->io_size, | ~~~~~~~~~~~~~~ | | | size_t {aka unsigned int} fs/iomap/buffered-io.c: In function 'iomap_ioend_can_merge': fs/iomap/buffered-io.c:1121:33: warning: format '%lu' expects argument of type 'long unsigned int', but argument 4 has type 'size_t' {aka 'unsigned int'} [-Wformat=] 1121 | "off 0x%llx, sect 0x%llx size %lu/0x%lx end 0x%llx, next off 0x%llx sect 0x%llx", | ~~^ | | | long unsigned int | %u ...... 1124 | ioend->io_size, (ioend->io_size >> 9), | ~~~~~~~~~~~~~~ | | | size_t {aka unsigned int} 1121 | "off 0x%llx, sect 0x%llx size %lu/0x%lx end 0x%llx, next off 0x%llx sect 0x%llx", | ~~^ | | | long unsigned int | %x ...... 1124 | ioend->io_size, (ioend->io_size >> 9), | ~~~~~~~~~~~~~~~~~~~~~ | | | size_t {aka unsigned int} vim +1093 fs/iomap/buffered-io.c 1072 1073 /* 1074 * Ioend completion routine for merged bios. This can only be called from task 1075 * contexts as merged ioends can be of unbound length. Hence we have to break up 1076 * the page writeback completion into manageable chunks to avoid long scheduler 1077 * holdoffs. We aim to keep scheduler holdoffs down below 10ms so that we get 1078 * good batch processing throughput without creating adverse scheduler latency 1079 * conditions. 1080 */ 1081 void 1082 iomap_finish_ioends(struct iomap_ioend *ioend, int error) 1083 { 1084 struct list_head tmp; 1085 u32 pages; 1086 1087 might_sleep(); 1088 1089 list_replace_init(&ioend->io_list, &tmp); 1090 pages = iomap_finish_ioend(ioend, error); 1091 1092 while (!list_empty(&tmp)) { 1094 ioend->io_pages, 1095 ioend->io_sector, 1096 ioend->io_size, 1097 pages); 1098 if (pages > 32768) { 1099 cond_resched(); 1100 pages = 0; 1101 } 1102 ioend = list_first_entry(&tmp, struct iomap_ioend, io_list); 1103 list_del_init(&ioend->io_list); 1104 pages += iomap_finish_ioend(ioend, error); 1105 } 1106 trace_printk("pages %u, start sector 0x%llx size %lu pcnt %u", 1107 ioend->io_pages, 1108 ioend->io_sector, 1109 ioend->io_size, 1110 pages); 1111 } 1112 EXPORT_SYMBOL_GPL(iomap_finish_ioends); 1113 1114 /* 1115 * We can merge two adjacent ioends if they have the same set of work to do. 1116 */ 1117 static bool 1118 iomap_ioend_can_merge(struct iomap_ioend *ioend, struct iomap_ioend *next) 1119 { 1120 trace_printk( 1122 ioend->io_offset, 1123 ioend->io_sector, 1124 ioend->io_size, (ioend->io_size >> 9), 1125 ioend->io_sector + (ioend->io_size >> 9), 1126 next->io_offset, 1127 next->io_sector); 1128 1129 if (ioend->io_bio->bi_status != next->io_bio->bi_status) 1130 return false; 1131 if ((ioend->io_flags & IOMAP_F_SHARED) ^ 1132 (next->io_flags & IOMAP_F_SHARED)) 1133 return false; 1134 if ((ioend->io_type == IOMAP_UNWRITTEN) ^ 1135 (next->io_type == IOMAP_UNWRITTEN)) 1136 return false; 1137 if (ioend->io_offset + ioend->io_size != next->io_offset) 1138 return false; 1139 /* 1140 * Do not merge physically discontiguous ioends. The filesystem 1141 * completion functions will have to iterate the physical 1142 * discontiguities even if we merge the ioends at a logical level, so 1143 * we don't gain anything by merging physical discontiguities here. 1144 */ 1145 1146 if (ioend->io_sector + (ioend->io_size >> 9) != next->io_sector) 1147 return false; 1148 return true; 1149 } 1150 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org