On 5/10/24 1:05 PM, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: dd5a440a31fa Linux 6.9-rc7 > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=11059824980000 > kernel config: https://syzkaller.appspot.com/x/.config?x=6d14c12b661fb43 > dashboard link: https://syzkaller.appspot.com/bug?extid=1ac5b398842451b74cec > compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 > > Unfortunately, I don't have any reproducer for this issue yet. > > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/58e2a4900479/disk-dd5a440a.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/246a109c32d6/vmlinux-dd5a440a.xz > kernel image: https://storage.googleapis.com/syzbot-assets/d2719f7eb672/bzImage-dd5a440a.xz > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+1ac5b398842451b74cec@xxxxxxxxxxxxxxxxxxxxxxxxx This looks like it was resolved by 6fe60465e1d5 - stack_depot_save_flags was losing __GFP_NOLOCKDEP #syz fix stackdepot: respect __GFP_NOLOCKDEP allocation flag (does this make syzbot re-test?) > ====================================================== > WARNING: possible circular locking dependency detected > 6.9.0-rc7-syzkaller #0 Not tainted > ------------------------------------------------------ > kswapd0/89 is trying to acquire lock: > ffff8880540b9858 > (&xfs_nondir_ilock_class#3){++++}-{3:3}, at: xfs_can_free_eofblocks+0x645/0x910 fs/xfs/xfs_bmap_util.c:555 > > but task is already holding lock: > ffffffff8e42a780 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6782 [inline] > ffffffff8e42a780 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xbe8/0x38a0 mm/vmscan.c:7164 > > which lock already depends on the new lock. > > > the existing dependency chain (in reverse order) is: > > -> #1 (fs_reclaim){+.+.}-{0:0}: > lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 > __fs_reclaim_acquire mm/page_alloc.c:3698 [inline] > fs_reclaim_acquire+0x88/0x140 mm/page_alloc.c:3712 > might_alloc include/linux/sched/mm.h:312 [inline] > slab_pre_alloc_hook mm/slub.c:3746 [inline] > slab_alloc_node mm/slub.c:3827 [inline] > kmalloc_trace+0x47/0x360 mm/slub.c:3992 > kmalloc include/linux/slab.h:628 [inline] > add_stack_record_to_list mm/page_owner.c:177 [inline] > inc_stack_record_count mm/page_owner.c:219 [inline] > __set_page_owner+0x561/0x810 mm/page_owner.c:334 > set_page_owner include/linux/page_owner.h:32 [inline] > post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1534 > prep_new_page mm/page_alloc.c:1541 [inline] > get_page_from_freelist+0x3410/0x35b0 mm/page_alloc.c:3317 > __alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575 > alloc_pages_mpol+0x3e8/0x680 mm/mempolicy.c:2264 > stack_depot_save_flags+0x666/0x830 lib/stackdepot.c:635 > kasan_save_stack mm/kasan/common.c:48 [inline] > kasan_save_track+0x51/0x80 mm/kasan/common.c:68 > poison_kmalloc_redzone mm/kasan/common.c:370 [inline] > __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387 > kasan_kmalloc include/linux/kasan.h:211 [inline] > kmalloc_trace+0x1db/0x360 mm/slub.c:3997 > kmalloc include/linux/slab.h:628 [inline] > kzalloc include/linux/slab.h:749 [inline] > xfs_iext_alloc_node fs/xfs/libxfs/xfs_iext_tree.c:401 [inline] > xfs_iext_alloc_root fs/xfs/libxfs/xfs_iext_tree.c:593 [inline] > xfs_iext_insert_raw+0x206/0x23d0 fs/xfs/libxfs/xfs_iext_tree.c:645 > xfs_iext_insert+0x38/0x250 fs/xfs/libxfs/xfs_iext_tree.c:684 > xfs_bmap_add_extent_hole_delay+0x573/0xc20 fs/xfs/libxfs/xfs_bmap.c:2686 > xfs_bmapi_reserve_delalloc+0x897/0x9b0 fs/xfs/libxfs/xfs_bmap.c:4128 > xfs_buffered_write_iomap_begin+0x1243/0x1b40 fs/xfs/xfs_iomap.c:1130 > iomap_iter+0x693/0xf60 fs/iomap/iter.c:91 > iomap_zero_range+0x16e/0x6e0 fs/iomap/buffered-io.c:1426 > xfs_setattr_size+0x384/0xc80 fs/xfs/xfs_iops.c:858 > xfs_vn_setattr+0x25d/0x320 fs/xfs/xfs_iops.c:1020 > notify_change+0xb9f/0xe70 fs/attr.c:497 > do_truncate fs/open.c:65 [inline] > do_ftruncate+0x46b/0x590 fs/open.c:181 > do_sys_ftruncate fs/open.c:199 [inline] > __do_sys_ftruncate fs/open.c:207 [inline] > __se_sys_ftruncate fs/open.c:205 [inline] > __x64_sys_ftruncate+0x95/0xf0 fs/open.c:205 > do_syscall_x64 arch/x86/entry/common.c:52 [inline] > do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 > entry_SYSCALL_64_after_hwframe+0x77/0x7f > > -> #0 (&xfs_nondir_ilock_class#3){++++}-{3:3}: > check_prev_add kernel/locking/lockdep.c:3134 [inline] > check_prevs_add kernel/locking/lockdep.c:3253 [inline] > validate_chain+0x18cb/0x58e0 kernel/locking/lockdep.c:3869 > __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 > lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 > down_read_nested+0xb5/0xa50 kernel/locking/rwsem.c:1651 > xfs_can_free_eofblocks+0x645/0x910 fs/xfs/xfs_bmap_util.c:555 > xfs_inode_mark_reclaimable+0x1bb/0xf60 fs/xfs/xfs_icache.c:2149 > destroy_inode fs/inode.c:311 [inline] > evict+0x54b/0x630 fs/inode.c:682 > dispose_list fs/inode.c:700 [inline] > prune_icache_sb+0x239/0x2f0 fs/inode.c:885 > super_cache_scan+0x38c/0x4b0 fs/super.c:223 > do_shrink_slab+0x707/0x1160 mm/shrinker.c:435 > shrink_slab_memcg mm/shrinker.c:548 [inline] > shrink_slab+0x883/0x14d0 mm/shrinker.c:626 > shrink_one+0x453/0x880 mm/vmscan.c:4774 > shrink_many mm/vmscan.c:4835 [inline] > lru_gen_shrink_node mm/vmscan.c:4935 [inline] > shrink_node+0x3b17/0x4310 mm/vmscan.c:5894 > kswapd_shrink_node mm/vmscan.c:6704 [inline] > balance_pgdat mm/vmscan.c:6895 [inline] > kswapd+0x1882/0x38a0 mm/vmscan.c:7164 > kthread+0x2f2/0x390 kernel/kthread.c:388 > ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 > > other info that might help us debug this: > > Possible unsafe locking scenario: > > CPU0 CPU1 > ---- ---- > lock(fs_reclaim); > lock(&xfs_nondir_ilock_class#3); > lock(fs_reclaim); > rlock(&xfs_nondir_ilock_class#3); > > *** DEADLOCK *** > > 2 locks held by kswapd0/89: > #0: ffffffff8e42a780 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6782 [inline] > #0: ffffffff8e42a780 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xbe8/0x38a0 mm/vmscan.c:7164 > #1: ffff8880796d20e0 (&type->s_umount_key#66){++++}-{3:3}, at: super_trylock_shared fs/super.c:561 [inline] > #1: ffff8880796d20e0 (&type->s_umount_key#66){++++}-{3:3}, at: super_cache_scan+0x94/0x4b0 fs/super.c:196 > > stack backtrace: > CPU: 0 PID: 89 Comm: kswapd0 Not tainted 6.9.0-rc7-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 > Call Trace: > <TASK> > __dump_stack lib/dump_stack.c:88 [inline] > dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 > check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2187 > check_prev_add kernel/locking/lockdep.c:3134 [inline] > check_prevs_add kernel/locking/lockdep.c:3253 [inline] > validate_chain+0x18cb/0x58e0 kernel/locking/lockdep.c:3869 > __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 > lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 > down_read_nested+0xb5/0xa50 kernel/locking/rwsem.c:1651 > xfs_can_free_eofblocks+0x645/0x910 fs/xfs/xfs_bmap_util.c:555 > xfs_inode_mark_reclaimable+0x1bb/0xf60 fs/xfs/xfs_icache.c:2149 > destroy_inode fs/inode.c:311 [inline] > evict+0x54b/0x630 fs/inode.c:682 > dispose_list fs/inode.c:700 [inline] > prune_icache_sb+0x239/0x2f0 fs/inode.c:885 > super_cache_scan+0x38c/0x4b0 fs/super.c:223 > do_shrink_slab+0x707/0x1160 mm/shrinker.c:435 > shrink_slab_memcg mm/shrinker.c:548 [inline] > shrink_slab+0x883/0x14d0 mm/shrinker.c:626 > shrink_one+0x453/0x880 mm/vmscan.c:4774 > shrink_many mm/vmscan.c:4835 [inline] > lru_gen_shrink_node mm/vmscan.c:4935 [inline] > shrink_node+0x3b17/0x4310 mm/vmscan.c:5894 > kswapd_shrink_node mm/vmscan.c:6704 [inline] > balance_pgdat mm/vmscan.c:6895 [inline] > kswapd+0x1882/0x38a0 mm/vmscan.c:7164 > kthread+0x2f2/0x390 kernel/kthread.c:388 > ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 > </TASK> > > > --- > This report is generated by a bot. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. > > syzbot will keep track of this issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > > If the report is already addressed, let syzbot know by replying with: > #syz fix: exact-commit-title > > If you want to overwrite report's subsystems, reply with: > #syz set subsystems: new-subsystem > (See the list of subsystem names on the web dashboard) > > If the report is a duplicate of another one, reply with: > #syz dup: exact-subject-of-another-report > > If you want to undo deduplication, reply with: > #syz undup >
