Hi Yu, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on tip/x86/core] [also build test WARNING on cgroup/for-next tip/x86/mm fuse/for-next tip/perf/core tip/sched/core linus/master v5.12-rc7] [cannot apply to hnaz-linux-mm/master next-20210413] [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/0day-ci/linux/commits/Yu-Zhao/Multigenerational-LRU-Framework/20210413-145844 base: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 99cb64de36d5c9397a664808b92943e35bdce25e compiler: h8300-linux-gcc (GCC) 9.3.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@xxxxxxxxx> cppcheck possible warnings: (new ones prefixed by >>, may not real problems) mm/vmscan.c:4110:22: warning: Local variable kswapd shadows outer function [shadowFunction] struct task_struct *kswapd = NODE_DATA(nid)->kswapd; ^ mm/vmscan.c:3912:12: note: Shadowed declaration static int kswapd(void *p) ^ mm/vmscan.c:4110:22: note: Shadow variable struct task_struct *kswapd = NODE_DATA(nid)->kswapd; ^ mm/vmscan.c:5460:7: warning: Identical inner 'if' condition is always true. [identicalInnerCondition] if (!args) ^ mm/vmscan.c:5435:15: note: 'alloc' is assigned value '!args' here. bool alloc = !args; ^ mm/vmscan.c:5458:6: note: outer condition: alloc if (alloc) { ^ mm/vmscan.c:5460:7: note: identical inner condition: !args if (!args) ^ >> mm/vmscan.c:6613:7: warning: %u in format string (no. 2) requires 'unsigned int *' but the argument type is 'signed int *'. [invalidScanfArgType_int] n = sscanf(cur, "%c %u %u %lu %n %u %n %lu %n", &cmd, &memcg_id, &nid, ^ mm/vmscan.c:6613:7: warning: %u in format string (no. 3) requires 'unsigned int *' but the argument type is 'signed int *'. [invalidScanfArgType_int] n = sscanf(cur, "%c %u %u %lu %n %u %n %lu %n", &cmd, &memcg_id, &nid, ^ mm/vmscan.c:6613:7: warning: %u in format string (no. 6) requires 'unsigned int *' but the argument type is 'signed int *'. [invalidScanfArgType_int] n = sscanf(cur, "%c %u %u %lu %n %u %n %lu %n", &cmd, &memcg_id, &nid, ^ mm/vmscan.c:4712:12: warning: Possible null pointer dereference: args [nullPointer] int nid = args->node_id; ^ mm/vmscan.c:5947:55: note: Calling function 'walk_mm_list', 5th argument 'NULL' value is 0 return walk_mm_list(lruvec, max_seq, sc, swappiness, NULL) ? nr_to_scan : 0; ^ mm/vmscan.c:5471:22: note: Calling function 'get_next_mm', 1st argument 'args' value is 0 last = get_next_mm(args, swappiness, &mm); ^ mm/vmscan.c:4803:32: note: Calling function 'reset_mm_stats', 3rd argument 'args' value is 0 reset_mm_stats(mm_list, last, args); ^ mm/vmscan.c:4712:12: note: Null pointer dereference int nid = args->node_id; ^ mm/vmscan.c:4713:32: warning: Possible null pointer dereference: args [nullPointer] int sid = sid_from_seq_or_gen(args->max_seq); ^ mm/vmscan.c:5947:55: note: Calling function 'walk_mm_list', 5th argument 'NULL' value is 0 return walk_mm_list(lruvec, max_seq, sc, swappiness, NULL) ? nr_to_scan : 0; ^ mm/vmscan.c:5471:22: note: Calling function 'get_next_mm', 1st argument 'args' value is 0 last = get_next_mm(args, swappiness, &mm); ^ mm/vmscan.c:4803:32: note: Calling function 'reset_mm_stats', 3rd argument 'args' value is 0 reset_mm_stats(mm_list, last, args); ^ mm/vmscan.c:4713:32: note: Null pointer dereference int sid = sid_from_seq_or_gen(args->max_seq); ^ mm/vmscan.c:4726:28: warning: Possible null pointer dereference: args [nullPointer] sid = sid_from_seq_or_gen(args->max_seq + 1); ^ mm/vmscan.c:5947:55: note: Calling function 'walk_mm_list', 5th argument 'NULL' value is 0 return walk_mm_list(lruvec, max_seq, sc, swappiness, NULL) ? nr_to_scan : 0; ^ mm/vmscan.c:5471:22: note: Calling function 'get_next_mm', 1st argument 'args' value is 0 last = get_next_mm(args, swappiness, &mm); ^ mm/vmscan.c:4803:32: note: Calling function 'reset_mm_stats', 3rd argument 'args' value is 0 reset_mm_stats(mm_list, last, args); ^ mm/vmscan.c:4726:28: note: Null pointer dereference sid = sid_from_seq_or_gen(args->max_seq + 1); ^ mm/vmscan.c:4758:12: warning: Possible null pointer dereference: args [nullPointer] int nid = args->node_id; ^ mm/vmscan.c:5947:55: note: Calling function 'walk_mm_list', 5th argument 'NULL' value is 0 return walk_mm_list(lruvec, max_seq, sc, swappiness, NULL) ? nr_to_scan : 0; ^ mm/vmscan.c:5471:22: note: Calling function 'get_next_mm', 1st argument 'args' value is 0 last = get_next_mm(args, swappiness, &mm); ^ mm/vmscan.c:4758:12: note: Null pointer dereference int nid = args->node_id; ^ mm/vmscan.c:4759:48: warning: Possible null pointer dereference: args [nullPointer] struct lru_gen_mm_list *mm_list = get_mm_list(args->memcg); ^ mm/vmscan.c:5947:55: note: Calling function 'walk_mm_list', 5th argument 'NULL' value is 0 return walk_mm_list(lruvec, max_seq, sc, swappiness, NULL) ? nr_to_scan : 0; ^ mm/vmscan.c:5471:22: note: Calling function 'get_next_mm', 1st argument 'args' value is 0 last = get_next_mm(args, swappiness, &mm); ^ mm/vmscan.c:4759:48: note: Null pointer dereference struct lru_gen_mm_list *mm_list = get_mm_list(args->memcg); ^ mm/vmscan.c:4768:12: warning: Possible null pointer dereference: args [nullPointer] VM_BUG_ON(args->max_seq > mm_list->nodes[nid].cur_seq + 1); ^ mm/vmscan.c:5947:55: note: Calling function 'walk_mm_list', 5th argument 'NULL' value is 0 return walk_mm_list(lruvec, max_seq, sc, swappiness, NULL) ? nr_to_scan : 0; ^ mm/vmscan.c:5471:22: note: Calling function 'get_next_mm', 1st argument 'args' value is 0 last = get_next_mm(args, swappiness, &mm); ^ mm/vmscan.c:4768:12: note: Null pointer dereference VM_BUG_ON(args->max_seq > mm_list->nodes[nid].cur_seq + 1); ^ mm/vmscan.c:4769:21: warning: Possible null pointer dereference: args [nullPointer] VM_BUG_ON(*iter && args->max_seq < mm_list->nodes[nid].cur_seq); ^ mm/vmscan.c:5947:55: note: Calling function 'walk_mm_list', 5th argument 'NULL' value is 0 return walk_mm_list(lruvec, max_seq, sc, swappiness, NULL) ? nr_to_scan : 0; ^ mm/vmscan.c:5471:22: note: Calling function 'get_next_mm', 1st argument 'args' value is 0 last = get_next_mm(args, swappiness, &mm); ^ mm/vmscan.c:4769:21: note: Null pointer dereference VM_BUG_ON(*iter && args->max_seq < mm_list->nodes[nid].cur_seq); vim +6613 mm/vmscan.c 6579 6580 static ssize_t lru_gen_seq_write(struct file *file, const char __user *src, 6581 size_t len, loff_t *pos) 6582 { 6583 void *buf; 6584 char *cur, *next; 6585 int err = 0; 6586 6587 buf = kvmalloc(len + 1, GFP_USER); 6588 if (!buf) 6589 return -ENOMEM; 6590 6591 if (copy_from_user(buf, src, len)) { 6592 kvfree(buf); 6593 return -EFAULT; 6594 } 6595 6596 next = buf; 6597 next[len] = '\0'; 6598 6599 while ((cur = strsep(&next, ",;\n"))) { 6600 int n; 6601 int end; 6602 char cmd; 6603 int memcg_id; 6604 int nid; 6605 unsigned long seq; 6606 int swappiness = -1; 6607 unsigned long nr_to_reclaim = -1; 6608 6609 cur = skip_spaces(cur); 6610 if (!*cur) 6611 continue; 6612 > 6613 n = sscanf(cur, "%c %u %u %lu %n %u %n %lu %n", &cmd, &memcg_id, &nid, 6614 &seq, &end, &swappiness, &end, &nr_to_reclaim, &end); 6615 if (n < 4 || cur[end]) { 6616 err = -EINVAL; 6617 break; 6618 } 6619 6620 err = advance_seq(cmd, memcg_id, nid, seq, swappiness, nr_to_reclaim); 6621 if (err) 6622 break; 6623 } 6624 6625 kvfree(buf); 6626 6627 return err ? : len; 6628 } 6629 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx
