====================================================== WARNING: possible circular locking dependency detected 6.9.0-rc4-next-20240418-syzkaller #0 Not tainted ------------------------------------------------------ kswapd0/88 is trying to acquire lock: ffff88805e86a018 (&xfs_nondir_ilock_class#3){++++}-{3:3}, at: xfs_reclaim_inode fs/xfs/xfs_icache.c:945 [inline] ffff88805e86a018 (&xfs_nondir_ilock_class#3){++++}-{3:3}, at: xfs_icwalk_process_inode fs/xfs/xfs_icache.c:1631 [inline] ffff88805e86a018 (&xfs_nondir_ilock_class#3){++++}-{3:3}, at: xfs_icwalk_ag+0x120e/0x1ad0 fs/xfs/xfs_icache.c:1713 but task is already holding lock: ffffffff8e429aa0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6819 [inline] ffffffff8e429aa0 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xbe8/0x38a0 mm/vmscan.c:7201 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:3827 [inline] fs_reclaim_acquire+0x88/0x140 mm/page_alloc.c:3841 might_alloc include/linux/sched/mm.h:334 [inline] slab_pre_alloc_hook mm/slub.c:3847 [inline] slab_alloc_node mm/slub.c:3937 [inline] kmalloc_trace_noprof+0x3d/0x2b0 mm/slub.c:4104 kmalloc_noprof include/linux/slab.h:660 [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+0x1f3/0x230 mm/page_alloc.c:1476 prep_new_page mm/page_alloc.c:1484 [inline] get_page_from_freelist+0x2ce2/0x2d90 mm/page_alloc.c:3446 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4704 __alloc_pages_node_noprof include/linux/gfp.h:244 [inline] alloc_pages_node_noprof include/linux/gfp.h:271 [inline] alloc_slab_page+0x5f/0x120 mm/slub.c:2259 allocate_slab+0x5a/0x2e0 mm/slub.c:2422 new_slab mm/slub.c:2475 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3624 __slab_alloc+0x58/0xa0 mm/slub.c:3714 __slab_alloc_node mm/slub.c:3767 [inline] slab_alloc_node mm/slub.c:3945 [inline] kmem_cache_alloc_noprof+0x1c1/0x290 mm/slub.c:3964 xfs_btree_alloc_cursor fs/xfs/libxfs/xfs_btree.h:679 [inline] xfs_refcountbt_init_cursor+0x65/0x2a0 fs/xfs/libxfs/xfs_refcount_btree.c:367 xfs_reflink_find_shared fs/xfs/xfs_reflink.c:147 [inline] xfs_reflink_trim_around_shared+0x53a/0x9d0 fs/xfs/xfs_reflink.c:194 xfs_buffered_write_iomap_begin+0xebf/0x1b40 fs/xfs/xfs_iomap.c:1062 iomap_iter+0x691/0xf60 fs/iomap/iter.c:91 iomap_file_buffered_write+0x26c/0xa60 fs/iomap/buffered-io.c:1014 xfs_file_buffered_write+0x2e4/0xad0 fs/xfs/xfs_file.c:786 new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa72/0xc90 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 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_write_nested+0x3d/0x50 kernel/locking/rwsem.c:1695 xfs_reclaim_inode fs/xfs/xfs_icache.c:945 [inline] xfs_icwalk_process_inode fs/xfs/xfs_icache.c:1631 [inline] xfs_icwalk_ag+0x120e/0x1ad0 fs/xfs/xfs_icache.c:1713 xfs_icwalk fs/xfs/xfs_icache.c:1762 [inline] xfs_reclaim_inodes_nr+0x257/0x360 fs/xfs/xfs_icache.c:1011 super_cache_scan+0x40f/0x4b0 fs/super.c:227 do_shrink_slab+0x705/0x1160 mm/shrinker.c:435 shrink_slab+0x1092/0x14d0 mm/shrinker.c:662 shrink_one+0x453/0x880 mm/vmscan.c:4809 shrink_many mm/vmscan.c:4870 [inline] lru_gen_shrink_node mm/vmscan.c:4970 [inline] shrink_node+0x3b17/0x4310 mm/vmscan.c:5929 kswapd_shrink_node mm/vmscan.c:6741 [inline] balance_pgdat mm/vmscan.c:6932 [inline] kswapd+0x1882/0x38a0 mm/vmscan.c:7201 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/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); lock(&xfs_nondir_ilock_class#3); *** DEADLOCK *** 2 locks held by kswapd0/88: #0: ffffffff8e429aa0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6819 [inline] #0: ffffffff8e429aa0 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xbe8/0x38a0 mm/vmscan.c:7201 #1: ffff88804cfd20e0 (&type->s_umount_key#77){++++}-{3:3}, at: super_trylock_shared fs/super.c:562 [inline] #1: ffff88804cfd20e0 (&type->s_umount_key#77){++++}-{3:3}, at: super_cache_scan+0x94/0x4b0 fs/super.c:196 stack backtrace: CPU: 0 PID: 88 Comm: kswapd0 Not tainted 6.9.0-rc4-next-20240418-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __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_write_nested+0x3d/0x50 kernel/locking/rwsem.c:1695 xfs_reclaim_inode fs/xfs/xfs_icache.c:945 [inline] xfs_icwalk_process_inode fs/xfs/xfs_icache.c:1631 [inline] xfs_icwalk_ag+0x120e/0x1ad0 fs/xfs/xfs_icache.c:1713 xfs_icwalk fs/xfs/xfs_icache.c:1762 [inline] xfs_reclaim_inodes_nr+0x257/0x360 fs/xfs/xfs_icache.c:1011 super_cache_scan+0x40f/0x4b0 fs/super.c:227 do_shrink_slab+0x705/0x1160 mm/shrinker.c:435 shrink_slab+0x1092/0x14d0 mm/shrinker.c:662 shrink_one+0x453/0x880 mm/vmscan.c:4809 shrink_many mm/vmscan.c:4870 [inline] lru_gen_shrink_node mm/vmscan.c:4970 [inline] shrink_node+0x3b17/0x4310 mm/vmscan.c:5929 kswapd_shrink_node mm/vmscan.c:6741 [inline] balance_pgdat mm/vmscan.c:6932 [inline] kswapd+0x1882/0x38a0 mm/vmscan.c:7201 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244