tree: https://gitee.com/openeuler/kernel.git openEuler-1.0-LTS head: bd6fde5ff5b73d04068bdad2dc7730479d4df355 commit: 2f5f99f3efc5d34c37f9918c50808a4cfe36c211 [1424/1424] mm: handle uninitialized numa nodes gracefully config: x86_64-buildonly-randconfig-004-20250217 (https://download.01.org/0day-ci/archive/20250217/202502171533.xL4t91Bt-lkp@i...) compiler: gcc-12 (Debian 12.2.0-14) 12.2.0 reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250217/202502171533.xL4t91Bt-lkp@i...) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@intel.com> | Closes: https://lore.kernel.org/oe-kbuild-all/202502171533.xL4t91Bt-lkp@intel.com/ All warnings (new ones prefixed by >>): mm/memory_hotplug.c: In function '__remove_section': mm/memory_hotplug.c:481:23: warning: variable 'start_pfn' set but not used [-Wunused-but-set-variable] 481 | unsigned long start_pfn; | ^~~~~~~~~ mm/memory_hotplug.c: In function 'hotadd_init_pgdat':

...

mm/memory_hotplug.c:926:23: warning: unused variable 'start_pfn' [-Wunused-variable] 926 | unsigned long start_pfn = PFN_DOWN(start); | ^~~~~~~~~ mm/memory_hotplug.c: At top level: mm/memory_hotplug.c:971:13: warning: 'rollback_node_hotadd' defined but not used [-Wunused-function] 971 | static void rollback_node_hotadd(int nid) | ^~~~~~~~~~~~~~~~~~~~ In file included from include/linux/migrate.h:6, from mm/memory_hotplug.c:27: include/linux/mempolicy.h:329:13: warning: '__do_mbind' defined but not used [-Wunused-function] 329 | static long __do_mbind(unsigned long start, unsigned long len, | ^~~~~~~~~~

vim +/start_pfn +926 mm/memory_hotplug.c 0bd85420087389 Tang Chen 2014-11-13 921 e13193319d3a55 Hidetoshi Seto 2009-11-17 922 /* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */ 2f5f99f3efc5d3 Michal Hocko 2023-11-08 923 static pg_data_t __ref *hotadd_init_pgdat(int nid, u64 start) 9af3c2dea3a3ae Yasunori Goto 2006-06-27 924 { 9af3c2dea3a3ae Yasunori Goto 2006-06-27 925 struct pglist_data *pgdat; c8e861a531b019 Fabian Frederick 2014-06-04 @926 unsigned long start_pfn = PFN_DOWN(start); 9af3c2dea3a3ae Yasunori Goto 2006-06-27 927 a1e565aa3cfc7c Tang Chen 2013-02-22 928 pgdat = NODE_DATA(nid); 9af3c2dea3a3ae Yasunori Goto 2006-06-27 929 2f5f99f3efc5d3 Michal Hocko 2023-11-08 930 /* 2f5f99f3efc5d3 Michal Hocko 2023-11-08 931 * NODE_DATA is preallocated (free_area_init) but its internal 2f5f99f3efc5d3 Michal Hocko 2023-11-08 932 * state is not allocated completely. Add missing pieces. 2f5f99f3efc5d3 Michal Hocko 2023-11-08 933 * Completely offline nodes stay around and they just need 2f5f99f3efc5d3 Michal Hocko 2023-11-08 934 * reintialization. 2f5f99f3efc5d3 Michal Hocko 2023-11-08 935 */ 2f5f99f3efc5d3 Michal Hocko 2023-11-08 936 if (pgdat->per_cpu_nodestats == &boot_nodestats) { b0dc3a342af36f Gu Zheng 2015-03-25 937 } else { e716f2eb24defb Mel Gorman 2017-05-03 938 /* e716f2eb24defb Mel Gorman 2017-05-03 939 * Reset the nr_zones, order and classzone_idx before reuse. e716f2eb24defb Mel Gorman 2017-05-03 940 * Note that kswapd will init kswapd_classzone_idx properly e716f2eb24defb Mel Gorman 2017-05-03 941 * when it starts in the near future. e716f2eb24defb Mel Gorman 2017-05-03 942 */ b0dc3a342af36f Gu Zheng 2015-03-25 943 pgdat->nr_zones = 0; 38087d9b036098 Mel Gorman 2016-07-28 944 pgdat->kswapd_order = 0; 38087d9b036098 Mel Gorman 2016-07-28 945 pgdat->kswapd_classzone_idx = 0; a1e565aa3cfc7c Tang Chen 2013-02-22 946 } 9af3c2dea3a3ae Yasunori Goto 2006-06-27 947 2f5f99f3efc5d3 Michal Hocko 2023-11-08 948 pgdat->node_start_pfn = 0; 03e85f9d5f1f8c Oscar Salvador 2018-08-21 949 9af3c2dea3a3ae Yasunori Goto 2006-06-27 950 /* init node's zones as empty zones, we don't have any present pages.*/ 03e85f9d5f1f8c Oscar Salvador 2018-08-21 951 free_area_init_core_hotplug(nid); 5830169f47269f Reza Arbab 2016-08-11 952 pgdat->per_cpu_nodestats = alloc_percpu(struct per_cpu_nodestat); 9af3c2dea3a3ae Yasunori Goto 2006-06-27 953 959ecc48fc7506 KAMEZAWA Hiroyuki 2011-06-15 954 /* 959ecc48fc7506 KAMEZAWA Hiroyuki 2011-06-15 955 * The node we allocated has no zone fallback lists. For avoiding 959ecc48fc7506 KAMEZAWA Hiroyuki 2011-06-15 956 * to access not-initialized zonelist, build here. 959ecc48fc7506 KAMEZAWA Hiroyuki 2011-06-15 957 */ 72675e131eb418 Michal Hocko 2017-09-06 958 build_all_zonelists(pgdat); 959ecc48fc7506 KAMEZAWA Hiroyuki 2011-06-15 959 0bd85420087389 Tang Chen 2014-11-13 960 /* 0bd85420087389 Tang Chen 2014-11-13 961 * When memory is hot-added, all the memory is in offline state. So 0bd85420087389 Tang Chen 2014-11-13 962 * clear all zones' present_pages because they will be updated in 0bd85420087389 Tang Chen 2014-11-13 963 * online_pages() and offline_pages(). 0bd85420087389 Tang Chen 2014-11-13 964 */ 03e85f9d5f1f8c Oscar Salvador 2018-08-21 965 reset_node_managed_pages(pgdat); 0bd85420087389 Tang Chen 2014-11-13 966 reset_node_present_pages(pgdat); 0bd85420087389 Tang Chen 2014-11-13 967 9af3c2dea3a3ae Yasunori Goto 2006-06-27 968 return pgdat; 9af3c2dea3a3ae Yasunori Goto 2006-06-27 969 } 9af3c2dea3a3ae Yasunori Goto 2006-06-27 970 b9ff036082cd17 Oscar Salvador 2018-08-17 @971 static void rollback_node_hotadd(int nid) 9af3c2dea3a3ae Yasunori Goto 2006-06-27 972 { b9ff036082cd17 Oscar Salvador 2018-08-17 973 pg_data_t *pgdat = NODE_DATA(nid); b9ff036082cd17 Oscar Salvador 2018-08-17 974 9af3c2dea3a3ae Yasunori Goto 2006-06-27 975 arch_refresh_nodedata(nid, NULL); 5830169f47269f Reza Arbab 2016-08-11 976 free_percpu(pgdat->per_cpu_nodestats); 9af3c2dea3a3ae Yasunori Goto 2006-06-27 977 arch_free_nodedata(pgdat); 9af3c2dea3a3ae Yasunori Goto 2006-06-27 978 return; 9af3c2dea3a3ae Yasunori Goto 2006-06-27 979 } 9af3c2dea3a3ae Yasunori Goto 2006-06-27 980 :::::: The code at line 926 was first introduced by commit :::::: c8e861a531b0199dc6ef9e402e29c474dfa507ce mm/memory_hotplug.c: use PFN_DOWN() :::::: TO: Fabian Frederick <fabf@skynet.be> :::::: CC: Linus Torvalds <torvalds@linux-foundation.org> -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki