CC: [email protected] BCC: [email protected] CC: [email protected] TO: "Liam R. Howlett" <[email protected]> CC: Johannes Weiner <[email protected]> CC: Andrew Morton <[email protected]> CC: Linux Memory Management List <[email protected]>
tree: https://github.com/hnaz/linux-mm master head: bf4803abaa3e9d2fa207c0675a2d2abf0fd44f66 commit: 48c8a6f751a2c87c2dcfa40442e0ebe3afd7cd76 [291/410] mm: remove rb tree. :::::: branch date: 3 days ago :::::: commit date: 3 days ago config: x86_64-randconfig-m001-20220425 (https://download.01.org/0day-ci/archive/20220430/[email protected]/config) compiler: gcc-11 (Debian 11.2.0-20) 11.2.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <[email protected]> Reported-by: Dan Carpenter <[email protected]> smatch warnings: mm/mmap.c:850 __vma_adjust() error: uninitialized symbol 'next_next'. vim +/next_next +850 mm/mmap.c ^1da177e4c3f415 Linus Torvalds 2005-04-16 608 ^1da177e4c3f415 Linus Torvalds 2005-04-16 609 /* ^1da177e4c3f415 Linus Torvalds 2005-04-16 610 * We cannot adjust vm_start, vm_end, vm_pgoff fields of a vma that ^1da177e4c3f415 Linus Torvalds 2005-04-16 611 * is already present in an i_mmap tree without adjusting the tree. ^1da177e4c3f415 Linus Torvalds 2005-04-16 612 * The following helper function should be used when such adjustments ^1da177e4c3f415 Linus Torvalds 2005-04-16 613 * are necessary. The "insert" vma (if any) is to be inserted ^1da177e4c3f415 Linus Torvalds 2005-04-16 614 * before we drop the necessary locks. ^1da177e4c3f415 Linus Torvalds 2005-04-16 615 */ e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 616 int __vma_adjust(struct vm_area_struct *vma, unsigned long start, e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 617 unsigned long end, pgoff_t pgoff, struct vm_area_struct *insert, e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 618 struct vm_area_struct *expand) ^1da177e4c3f415 Linus Torvalds 2005-04-16 619 { ^1da177e4c3f415 Linus Torvalds 2005-04-16 620 struct mm_struct *mm = vma->vm_mm; 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 621 struct vm_area_struct *next_next, *next = find_vma(mm, vma->vm_end); 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 622 struct vm_area_struct *orig_vma = vma; ^1da177e4c3f415 Linus Torvalds 2005-04-16 623 struct address_space *mapping = NULL; f808c13fd373894 Davidlohr Bueso 2017-09-08 624 struct rb_root_cached *root = NULL; 012f18004da33ba Rik van Riel 2010-08-09 625 struct anon_vma *anon_vma = NULL; ^1da177e4c3f415 Linus Torvalds 2005-04-16 626 struct file *file = vma->vm_file; 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 627 bool vma_changed = false; ^1da177e4c3f415 Linus Torvalds 2005-04-16 628 long adjust_next = 0; ^1da177e4c3f415 Linus Torvalds 2005-04-16 629 int remove_next = 0; f90a08f5f1a5029 Liam R. Howlett 2022-04-26 630 MA_STATE(mas, &mm->mm_mt, 0, 0); 734537c9cb725fc Kirill A. Shutemov 2016-07-28 631 struct vm_area_struct *exporter = NULL, *importer = NULL; 287d97ac0321367 Linus Torvalds 2010-04-10 632 f90a08f5f1a5029 Liam R. Howlett 2022-04-26 633 if (next && !insert) { ^1da177e4c3f415 Linus Torvalds 2005-04-16 634 if (end >= next->vm_end) { ^1da177e4c3f415 Linus Torvalds 2005-04-16 635 /* ^1da177e4c3f415 Linus Torvalds 2005-04-16 636 * vma expands, overlapping all the next, and ^1da177e4c3f415 Linus Torvalds 2005-04-16 637 * perhaps the one after too (mprotect case 6). 86d12e471d9f152 Andrea Arcangeli 2016-10-07 638 * The only other cases that gets here are e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 639 * case 1, case 7 and case 8. e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 640 */ e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 641 if (next == expand) { e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 642 /* e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 643 * The only case where we don't expand "vma" e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 644 * and we expand "next" instead is case 8. e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 645 */ e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 646 VM_WARN_ON(end != next->vm_end); e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 647 /* e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 648 * remove_next == 3 means we're e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 649 * removing "vma" and that to do so we e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 650 * swapped "vma" and "next". e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 651 */ e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 652 remove_next = 3; e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 653 VM_WARN_ON(file != next->vm_file); e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 654 swap(vma, next); e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 655 } else { e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 656 VM_WARN_ON(expand != vma); e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 657 /* e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 658 * case 1, 6, 7, remove_next == 2 is case 6, e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 659 * remove_next == 1 is case 1 or 7. ^1da177e4c3f415 Linus Torvalds 2005-04-16 660 */ 734537c9cb725fc Kirill A. Shutemov 2016-07-28 661 remove_next = 1 + (end > next->vm_end); 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 662 next_next = find_vma(mm, next->vm_end); e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 663 VM_WARN_ON(remove_next == 2 && 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 664 end != next_next->vm_end); e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 665 /* trim end to next, for case 6 first pass */ ^1da177e4c3f415 Linus Torvalds 2005-04-16 666 end = next->vm_end; e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 667 } e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 668 287d97ac0321367 Linus Torvalds 2010-04-10 669 exporter = next; ^1da177e4c3f415 Linus Torvalds 2005-04-16 670 importer = vma; 734537c9cb725fc Kirill A. Shutemov 2016-07-28 671 734537c9cb725fc Kirill A. Shutemov 2016-07-28 672 /* 734537c9cb725fc Kirill A. Shutemov 2016-07-28 673 * If next doesn't have anon_vma, import from vma after 734537c9cb725fc Kirill A. Shutemov 2016-07-28 674 * next, if the vma overlaps with it. 734537c9cb725fc Kirill A. Shutemov 2016-07-28 675 */ 97a42cd4398162a Andrea Arcangeli 2016-10-07 676 if (remove_next == 2 && !next->anon_vma) 734537c9cb725fc Kirill A. Shutemov 2016-07-28 677 exporter = next->vm_next; 734537c9cb725fc Kirill A. Shutemov 2016-07-28 678 ^1da177e4c3f415 Linus Torvalds 2005-04-16 679 } else if (end > next->vm_start) { ^1da177e4c3f415 Linus Torvalds 2005-04-16 680 /* ^1da177e4c3f415 Linus Torvalds 2005-04-16 681 * vma expands, overlapping part of the next: ^1da177e4c3f415 Linus Torvalds 2005-04-16 682 * mprotect case 5 shifting the boundary up. ^1da177e4c3f415 Linus Torvalds 2005-04-16 683 */ f9d86a60572295e Wei Yang 2020-10-13 684 adjust_next = (end - next->vm_start); 287d97ac0321367 Linus Torvalds 2010-04-10 685 exporter = next; ^1da177e4c3f415 Linus Torvalds 2005-04-16 686 importer = vma; e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 687 VM_WARN_ON(expand != importer); ^1da177e4c3f415 Linus Torvalds 2005-04-16 688 } else if (end < vma->vm_end) { ^1da177e4c3f415 Linus Torvalds 2005-04-16 689 /* ^1da177e4c3f415 Linus Torvalds 2005-04-16 690 * vma shrinks, and !insert tells it's not ^1da177e4c3f415 Linus Torvalds 2005-04-16 691 * split_vma inserting another: so it must be ^1da177e4c3f415 Linus Torvalds 2005-04-16 692 * mprotect case 4 shifting the boundary down. ^1da177e4c3f415 Linus Torvalds 2005-04-16 693 */ f9d86a60572295e Wei Yang 2020-10-13 694 adjust_next = -(vma->vm_end - end); 287d97ac0321367 Linus Torvalds 2010-04-10 695 exporter = vma; ^1da177e4c3f415 Linus Torvalds 2005-04-16 696 importer = next; e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 697 VM_WARN_ON(expand != importer); ^1da177e4c3f415 Linus Torvalds 2005-04-16 698 } ^1da177e4c3f415 Linus Torvalds 2005-04-16 699 5beb49305251e56 Rik van Riel 2010-03-05 700 /* 5beb49305251e56 Rik van Riel 2010-03-05 701 * Easily overlooked: when mprotect shifts the boundary, 5beb49305251e56 Rik van Riel 2010-03-05 702 * make sure the expanding vma has anon_vma set if the 5beb49305251e56 Rik van Riel 2010-03-05 703 * shrinking vma had, to cover any anon pages imported. 5beb49305251e56 Rik van Riel 2010-03-05 704 */ 287d97ac0321367 Linus Torvalds 2010-04-10 705 if (exporter && exporter->anon_vma && !importer->anon_vma) { c4ea95d7cd08d9f Daniel Forrest 2014-12-02 706 int error; c4ea95d7cd08d9f Daniel Forrest 2014-12-02 707 b800c91a0517071 Konstantin Khlebnikov 2015-01-11 708 importer->anon_vma = exporter->anon_vma; c4ea95d7cd08d9f Daniel Forrest 2014-12-02 709 error = anon_vma_clone(importer, exporter); 3fe89b3e2a7bbf3 Leon Yu 2015-03-25 710 if (error) c4ea95d7cd08d9f Daniel Forrest 2014-12-02 711 return error; b800c91a0517071 Konstantin Khlebnikov 2015-01-11 712 } 5beb49305251e56 Rik van Riel 2010-03-05 713 } 734537c9cb725fc Kirill A. Shutemov 2016-07-28 714 again: e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 715 vma_adjust_trans_huge(orig_vma, start, end, adjust_next); 37f9f5595c26d3c Kirill A. Shutemov 2016-07-26 716 f90a08f5f1a5029 Liam R. Howlett 2022-04-26 717 if (mas_preallocate(&mas, vma, GFP_KERNEL)) { f90a08f5f1a5029 Liam R. Howlett 2022-04-26 718 if (exporter && exporter->anon_vma) f90a08f5f1a5029 Liam R. Howlett 2022-04-26 719 unlink_anon_vmas(importer); f90a08f5f1a5029 Liam R. Howlett 2022-04-26 720 return -ENOMEM; f90a08f5f1a5029 Liam R. Howlett 2022-04-26 721 } f90a08f5f1a5029 Liam R. Howlett 2022-04-26 722 ^1da177e4c3f415 Linus Torvalds 2005-04-16 723 if (file) { ^1da177e4c3f415 Linus Torvalds 2005-04-16 724 mapping = file->f_mapping; ^1da177e4c3f415 Linus Torvalds 2005-04-16 725 root = &mapping->i_mmap; cbc91f71b51b833 Srikar Dronamraju 2012-04-11 726 uprobe_munmap(vma, vma->vm_start, vma->vm_end); 682968e0c425c60 Srikar Dronamraju 2012-03-30 727 682968e0c425c60 Srikar Dronamraju 2012-03-30 728 if (adjust_next) 27ba0644ea9dfe6 Kirill A. Shutemov 2015-02-10 729 uprobe_munmap(next, next->vm_start, next->vm_end); 682968e0c425c60 Srikar Dronamraju 2012-03-30 730 83cde9e8ba95d18 Davidlohr Bueso 2014-12-12 731 i_mmap_lock_write(mapping); ^1da177e4c3f415 Linus Torvalds 2005-04-16 732 if (insert) { ^1da177e4c3f415 Linus Torvalds 2005-04-16 733 /* 6b2dbba8b6ac4df Michel Lespinasse 2012-10-08 734 * Put into interval tree now, so instantiated pages ^1da177e4c3f415 Linus Torvalds 2005-04-16 735 * are visible to arm/parisc __flush_dcache_page ^1da177e4c3f415 Linus Torvalds 2005-04-16 736 * throughout; but we cannot insert into address ^1da177e4c3f415 Linus Torvalds 2005-04-16 737 * space until vma start or end is updated. ^1da177e4c3f415 Linus Torvalds 2005-04-16 738 */ ^1da177e4c3f415 Linus Torvalds 2005-04-16 739 __vma_link_file(insert); ^1da177e4c3f415 Linus Torvalds 2005-04-16 740 } ^1da177e4c3f415 Linus Torvalds 2005-04-16 741 } ^1da177e4c3f415 Linus Torvalds 2005-04-16 742 012f18004da33ba Rik van Riel 2010-08-09 743 anon_vma = vma->anon_vma; bf181b9f9d8dfbb Michel Lespinasse 2012-10-08 744 if (!anon_vma && adjust_next) bf181b9f9d8dfbb Michel Lespinasse 2012-10-08 745 anon_vma = next->anon_vma; bf181b9f9d8dfbb Michel Lespinasse 2012-10-08 746 if (anon_vma) { e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 747 VM_WARN_ON(adjust_next && next->anon_vma && e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 748 anon_vma != next->anon_vma); 4fc3f1d66b1ef0d Ingo Molnar 2012-12-02 749 anon_vma_lock_write(anon_vma); bf181b9f9d8dfbb Michel Lespinasse 2012-10-08 750 anon_vma_interval_tree_pre_update_vma(vma); bf181b9f9d8dfbb Michel Lespinasse 2012-10-08 751 if (adjust_next) bf181b9f9d8dfbb Michel Lespinasse 2012-10-08 752 anon_vma_interval_tree_pre_update_vma(next); bf181b9f9d8dfbb Michel Lespinasse 2012-10-08 753 } 012f18004da33ba Rik van Riel 2010-08-09 754 0fc48a6e213ab8e Wei Yang 2020-10-13 755 if (file) { ^1da177e4c3f415 Linus Torvalds 2005-04-16 756 flush_dcache_mmap_lock(mapping); 6b2dbba8b6ac4df Michel Lespinasse 2012-10-08 757 vma_interval_tree_remove(vma, root); ^1da177e4c3f415 Linus Torvalds 2005-04-16 758 if (adjust_next) 6b2dbba8b6ac4df Michel Lespinasse 2012-10-08 759 vma_interval_tree_remove(next, root); ^1da177e4c3f415 Linus Torvalds 2005-04-16 760 } ^1da177e4c3f415 Linus Torvalds 2005-04-16 761 d37371870ceb1d2 Michel Lespinasse 2012-12-11 762 if (start != vma->vm_start) { 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 763 if (vma->vm_start < start) 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 764 vma_mt_szero(mm, vma->vm_start, start); 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 765 else 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 766 vma_changed = true; ^1da177e4c3f415 Linus Torvalds 2005-04-16 767 vma->vm_start = start; d37371870ceb1d2 Michel Lespinasse 2012-12-11 768 } d37371870ceb1d2 Michel Lespinasse 2012-12-11 769 if (end != vma->vm_end) { 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 770 if (vma->vm_end > end) 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 771 vma_mt_szero(mm, end, vma->vm_end); 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 772 else 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 773 vma_changed = true; ^1da177e4c3f415 Linus Torvalds 2005-04-16 774 vma->vm_end = end; 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 775 if (!next) 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 776 mm->highest_vm_end = vm_end_gap(vma); d37371870ceb1d2 Michel Lespinasse 2012-12-11 777 } f90a08f5f1a5029 Liam R. Howlett 2022-04-26 778 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 779 if (vma_changed) f90a08f5f1a5029 Liam R. Howlett 2022-04-26 780 vma_mas_store(vma, &mas); f90a08f5f1a5029 Liam R. Howlett 2022-04-26 781 ^1da177e4c3f415 Linus Torvalds 2005-04-16 782 vma->vm_pgoff = pgoff; ^1da177e4c3f415 Linus Torvalds 2005-04-16 783 if (adjust_next) { f9d86a60572295e Wei Yang 2020-10-13 784 next->vm_start += adjust_next; f9d86a60572295e Wei Yang 2020-10-13 785 next->vm_pgoff += adjust_next >> PAGE_SHIFT; f90a08f5f1a5029 Liam R. Howlett 2022-04-26 786 vma_mas_store(next, &mas); ^1da177e4c3f415 Linus Torvalds 2005-04-16 787 } ^1da177e4c3f415 Linus Torvalds 2005-04-16 788 0fc48a6e213ab8e Wei Yang 2020-10-13 789 if (file) { ^1da177e4c3f415 Linus Torvalds 2005-04-16 790 if (adjust_next) 6b2dbba8b6ac4df Michel Lespinasse 2012-10-08 791 vma_interval_tree_insert(next, root); 6b2dbba8b6ac4df Michel Lespinasse 2012-10-08 792 vma_interval_tree_insert(vma, root); ^1da177e4c3f415 Linus Torvalds 2005-04-16 793 flush_dcache_mmap_unlock(mapping); ^1da177e4c3f415 Linus Torvalds 2005-04-16 794 } ^1da177e4c3f415 Linus Torvalds 2005-04-16 795 ^1da177e4c3f415 Linus Torvalds 2005-04-16 796 if (remove_next) { 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 797 __vma_unlink_list(mm, next); 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 798 /* Kill the cache */ 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 799 vmacache_invalidate(mm); ^1da177e4c3f415 Linus Torvalds 2005-04-16 800 if (file) ^1da177e4c3f415 Linus Torvalds 2005-04-16 801 __remove_shared_vm_struct(next, file, mapping); ^1da177e4c3f415 Linus Torvalds 2005-04-16 802 } else if (insert) { ^1da177e4c3f415 Linus Torvalds 2005-04-16 803 /* ^1da177e4c3f415 Linus Torvalds 2005-04-16 804 * split_vma has split insert from vma, and needs ^1da177e4c3f415 Linus Torvalds 2005-04-16 805 * us to insert it before dropping the locks ^1da177e4c3f415 Linus Torvalds 2005-04-16 806 * (it may either follow vma or precede it). ^1da177e4c3f415 Linus Torvalds 2005-04-16 807 */ f90a08f5f1a5029 Liam R. Howlett 2022-04-26 808 __insert_vm_struct(mm, &mas, insert); ^1da177e4c3f415 Linus Torvalds 2005-04-16 809 } ^1da177e4c3f415 Linus Torvalds 2005-04-16 810 bf181b9f9d8dfbb Michel Lespinasse 2012-10-08 811 if (anon_vma) { bf181b9f9d8dfbb Michel Lespinasse 2012-10-08 812 anon_vma_interval_tree_post_update_vma(vma); bf181b9f9d8dfbb Michel Lespinasse 2012-10-08 813 if (adjust_next) bf181b9f9d8dfbb Michel Lespinasse 2012-10-08 814 anon_vma_interval_tree_post_update_vma(next); 08b52706d505658 Konstantin Khlebnikov 2013-02-22 815 anon_vma_unlock_write(anon_vma); bf181b9f9d8dfbb Michel Lespinasse 2012-10-08 816 } ^1da177e4c3f415 Linus Torvalds 2005-04-16 817 0fc48a6e213ab8e Wei Yang 2020-10-13 818 if (file) { 808fbdbea05f1e9 Wei Yang 2020-10-13 819 i_mmap_unlock_write(mapping); 7b2d81d48a2d8e3 Ingo Molnar 2012-02-17 820 uprobe_mmap(vma); 2b144498350860b Srikar Dronamraju 2012-02-09 821 2b144498350860b Srikar Dronamraju 2012-02-09 822 if (adjust_next) 7b2d81d48a2d8e3 Ingo Molnar 2012-02-17 823 uprobe_mmap(next); 2b144498350860b Srikar Dronamraju 2012-02-09 824 } 2b144498350860b Srikar Dronamraju 2012-02-09 825 ^1da177e4c3f415 Linus Torvalds 2005-04-16 826 if (remove_next) { 925d1c401fa6cfd Matt Helsley 2008-04-29 827 if (file) { cbc91f71b51b833 Srikar Dronamraju 2012-04-11 828 uprobe_munmap(next, next->vm_start, next->vm_end); ^1da177e4c3f415 Linus Torvalds 2005-04-16 829 fput(file); 925d1c401fa6cfd Matt Helsley 2008-04-29 830 } 5beb49305251e56 Rik van Riel 2010-03-05 831 if (next->anon_vma) 5beb49305251e56 Rik van Riel 2010-03-05 832 anon_vma_merge(vma, next); ^1da177e4c3f415 Linus Torvalds 2005-04-16 833 mm->map_count--; 3964acd0dbec123 Oleg Nesterov 2013-07-31 834 mpol_put(vma_policy(next)); 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 835 BUG_ON(vma->vm_end < next->vm_end); 3928d4f5ee37cdc Linus Torvalds 2018-07-21 836 vm_area_free(next); 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 837 ^1da177e4c3f415 Linus Torvalds 2005-04-16 838 /* ^1da177e4c3f415 Linus Torvalds 2005-04-16 839 * In mprotect's case 6 (see comments on vma_merge), ^1da177e4c3f415 Linus Torvalds 2005-04-16 840 * we must remove another next too. It would clutter ^1da177e4c3f415 Linus Torvalds 2005-04-16 841 * up the code too much to do both in one go. ^1da177e4c3f415 Linus Torvalds 2005-04-16 842 */ e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 843 if (remove_next != 3) { e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 844 /* e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 845 * If "next" was removed and vma->vm_end was e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 846 * expanded (up) over it, in turn e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 847 * "next->vm_prev->vm_end" changed and the e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 848 * "vma->vm_next" gap must be updated. e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 849 */ 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 @850 next = next_next; e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 851 } else { e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 852 /* e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 853 * For the scope of the comment "next" and e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 854 * "vma" considered pre-swap(): if "vma" was e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 855 * removed, next->vm_start was expanded (down) e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 856 * over it and the "next" gap must be updated. e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 857 * Because of the swap() the post-swap() "vma" e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 858 * actually points to pre-swap() "next" e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 859 * (post-swap() "next" as opposed is now a e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 860 * dangling pointer). e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 861 */ e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 862 next = vma; e86f15ee64d8ee4 Andrea Arcangeli 2016-10-07 863 } 734537c9cb725fc Kirill A. Shutemov 2016-07-28 864 if (remove_next == 2) { 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 865 mas_reset(&mas); 734537c9cb725fc Kirill A. Shutemov 2016-07-28 866 remove_next = 1; 734537c9cb725fc Kirill A. Shutemov 2016-07-28 867 end = next->vm_end; ^1da177e4c3f415 Linus Torvalds 2005-04-16 868 goto again; 48c8a6f751a2c87 Liam R. Howlett 2022-04-26 869 } else if (!next) { fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 870 /* fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 871 * If remove_next == 2 we obviously can't fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 872 * reach this path. fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 873 * fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 874 * If remove_next == 3 we can't reach this fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 875 * path because pre-swap() next is always not fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 876 * NULL. pre-swap() "next" is not being fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 877 * removed and its next->vm_end is not altered fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 878 * (and furthermore "end" already matches fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 879 * next->vm_end in remove_next == 3). fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 880 * fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 881 * We reach this only in the remove_next == 1 fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 882 * case if the "next" vma that was removed was fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 883 * the highest vma of the mm. However in such fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 884 * case next->vm_end == "end" and the extended fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 885 * "vma" has vma->vm_end == next->vm_end so fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 886 * mm->highest_vm_end doesn't need any update fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 887 * in remove_next == 1 case. fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 888 */ 1be7107fbe18eed Hugh Dickins 2017-06-19 889 VM_WARN_ON(mm->highest_vm_end != vm_end_gap(vma)); fb8c41e9ad1f356 Andrea Arcangeli 2016-10-07 890 } ^1da177e4c3f415 Linus Torvalds 2005-04-16 891 } 2b144498350860b Srikar Dronamraju 2012-02-09 892 if (insert && file) 7b2d81d48a2d8e3 Ingo Molnar 2012-02-17 893 uprobe_mmap(insert); ^1da177e4c3f415 Linus Torvalds 2005-04-16 894 ^1da177e4c3f415 Linus Torvalds 2005-04-16 895 validate_mm(mm); 5beb49305251e56 Rik van Riel 2010-03-05 896 return 0; ^1da177e4c3f415 Linus Torvalds 2005-04-16 897 } ^1da177e4c3f415 Linus Torvalds 2005-04-16 898 -- 0-DAY CI Kernel Test Service https://01.org/lkp _______________________________________________ kbuild mailing list -- [email protected] To unsubscribe send an email to [email protected]
