Hello, It looks like an unlock may be needed o lines 721 and 732. julia ---------- Forwarded message ---------- Hi Alexey, I love your patch! Perhaps something to improve: [auto build test WARNING on jeyu/modules-next] [also build test WARNING on linus/master v5.6-rc2 next-20200218] [cannot apply to linux/master] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system. BTW, we also suggest to use '--base' option to specify the base tree in git format-patch, please see https://stackoverflow.com/a/37406982] url: https://github.com/0day-ci/linux/commits/Alexey-Dobriyan/proc-faster-open-read-close-with-permanent-files/20200218-231203 base: https://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux.git modules-next :::::: branch date: 6 hours ago :::::: commit date: 6 hours ago If you fix the issue, kindly add following tag Reported-by: kbuild test robot <lkp@xxxxxxxxx> Reported-by: Julia Lawall <julia.lawall@xxxxxxx> >> fs/proc/generic.c:721:2-8: preceding lock on line 706 fs/proc/generic.c:732:4-10: preceding lock on line 706 fs/proc/generic.c:732:4-10: preceding lock on line 748 # https://github.com/0day-ci/linux/commit/3cd4ad42ca7c52d1513e7ba9f08a06197a7380c8 git remote add linux-review https://github.com/0day-ci/linux git remote update linux-review git checkout 3cd4ad42ca7c52d1513e7ba9f08a06197a7380c8 vim +721 fs/proc/generic.c 8ce584c7416d8a Al Viro 2013-03-30 699 8ce584c7416d8a Al Viro 2013-03-30 700 int remove_proc_subtree(const char *name, struct proc_dir_entry *parent) 8ce584c7416d8a Al Viro 2013-03-30 701 { 8ce584c7416d8a Al Viro 2013-03-30 702 struct proc_dir_entry *root = NULL, *de, *next; 8ce584c7416d8a Al Viro 2013-03-30 703 const char *fn = name; 8ce584c7416d8a Al Viro 2013-03-30 704 unsigned int len; 8ce584c7416d8a Al Viro 2013-03-30 705 ecf1a3dfff22bd Waiman Long 2015-09-09 @706 write_lock(&proc_subdir_lock); 8ce584c7416d8a Al Viro 2013-03-30 707 if (__xlate_proc_name(name, &parent, &fn) != 0) { ecf1a3dfff22bd Waiman Long 2015-09-09 708 write_unlock(&proc_subdir_lock); 8ce584c7416d8a Al Viro 2013-03-30 709 return -ENOENT; 8ce584c7416d8a Al Viro 2013-03-30 710 } 8ce584c7416d8a Al Viro 2013-03-30 711 len = strlen(fn); 8ce584c7416d8a Al Viro 2013-03-30 712 710585d4922fd3 Nicolas Dichtel 2014-12-10 713 root = pde_subdir_find(parent, fn, len); 8ce584c7416d8a Al Viro 2013-03-30 714 if (!root) { ecf1a3dfff22bd Waiman Long 2015-09-09 715 write_unlock(&proc_subdir_lock); 8ce584c7416d8a Al Viro 2013-03-30 716 return -ENOENT; 8ce584c7416d8a Al Viro 2013-03-30 717 } 3cd4ad42ca7c52 Alexey Dobriyan 2020-02-16 718 if (unlikely(pde_is_permanent(root))) { 3cd4ad42ca7c52 Alexey Dobriyan 2020-02-16 719 WARN(1, "removing permanent /proc entry '%s/%s'", 3cd4ad42ca7c52 Alexey Dobriyan 2020-02-16 720 root->parent->name, root->name); 3cd4ad42ca7c52 Alexey Dobriyan 2020-02-16 @721 return -EINVAL; 3cd4ad42ca7c52 Alexey Dobriyan 2020-02-16 722 } 4f1134370a29a5 Alexey Dobriyan 2018-04-10 723 rb_erase(&root->subdir_node, &parent->subdir); 710585d4922fd3 Nicolas Dichtel 2014-12-10 724 8ce584c7416d8a Al Viro 2013-03-30 725 de = root; 8ce584c7416d8a Al Viro 2013-03-30 726 while (1) { 710585d4922fd3 Nicolas Dichtel 2014-12-10 727 next = pde_subdir_first(de); 8ce584c7416d8a Al Viro 2013-03-30 728 if (next) { 3cd4ad42ca7c52 Alexey Dobriyan 2020-02-16 729 if (unlikely(pde_is_permanent(root))) { 3cd4ad42ca7c52 Alexey Dobriyan 2020-02-16 730 WARN(1, "removing permanent /proc entry '%s/%s'", 3cd4ad42ca7c52 Alexey Dobriyan 2020-02-16 731 next->parent->name, next->name); 3cd4ad42ca7c52 Alexey Dobriyan 2020-02-16 732 return -EINVAL; 3cd4ad42ca7c52 Alexey Dobriyan 2020-02-16 733 } 4f1134370a29a5 Alexey Dobriyan 2018-04-10 734 rb_erase(&next->subdir_node, &de->subdir); 8ce584c7416d8a Al Viro 2013-03-30 735 de = next; 8ce584c7416d8a Al Viro 2013-03-30 736 continue; 8ce584c7416d8a Al Viro 2013-03-30 737 } 8ce584c7416d8a Al Viro 2013-03-30 738 next = de->parent; 8ce584c7416d8a Al Viro 2013-03-30 739 if (S_ISDIR(de->mode)) 8ce584c7416d8a Al Viro 2013-03-30 740 next->nlink--; e06689bf57017a Alexey Dobriyan 2019-12-04 741 write_unlock(&proc_subdir_lock); e06689bf57017a Alexey Dobriyan 2019-12-04 742 e06689bf57017a Alexey Dobriyan 2019-12-04 743 proc_entry_rundown(de); 8ce584c7416d8a Al Viro 2013-03-30 744 if (de == root) 8ce584c7416d8a Al Viro 2013-03-30 745 break; 8ce584c7416d8a Al Viro 2013-03-30 746 pde_put(de); 8ce584c7416d8a Al Viro 2013-03-30 747 ecf1a3dfff22bd Waiman Long 2015-09-09 748 write_lock(&proc_subdir_lock); 8ce584c7416d8a Al Viro 2013-03-30 749 de = next; 8ce584c7416d8a Al Viro 2013-03-30 750 } 8ce584c7416d8a Al Viro 2013-03-30 751 pde_put(root); 8ce584c7416d8a Al Viro 2013-03-30 752 return 0; 8ce584c7416d8a Al Viro 2013-03-30 753 } 8ce584c7416d8a Al Viro 2013-03-30 754 EXPORT_SYMBOL(remove_proc_subtree); 4a520d2769beb7 David Howells 2013-04-12 755 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx