WARNING: possible circular locking dependency detected 6.10.0-rc5-syzkaller-00018-g55027e689933 #0 Not tainted ------------------------------------------------------ kswapd0/112 is trying to acquire lock: ffff888026fda610 (sb_internal){.+.+}-{0:0}, at: evict+0x2ed/0x6c0 fs/inode.c:667 but task is already holding lock: ffffffff8dd3ab20 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x166/0x1970 mm/vmscan.c:6798 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (fs_reclaim){+.+.}-{0:0}: __fs_reclaim_acquire mm/page_alloc.c:3801 [inline] fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3815 might_alloc include/linux/sched/mm.h:334 [inline] slab_pre_alloc_hook mm/slub.c:3891 [inline] slab_alloc_node mm/slub.c:3981 [inline] __do_kmalloc_node mm/slub.c:4121 [inline] __kmalloc_node_noprof+0xbb/0x450 mm/slub.c:4129 kmalloc_node_noprof include/linux/slab.h:681 [inline] kvmalloc_node_noprof+0x9d/0x1a0 mm/util.c:634 ext4_xattr_inode_cache_find fs/ext4/xattr.c:1535 [inline] ext4_xattr_inode_lookup_create fs/ext4/xattr.c:1581 [inline] ext4_xattr_inode_lookup_create+0x4e8/0x1910 fs/ext4/xattr.c:1568 ext4_xattr_block_set+0x77a/0x3090 fs/ext4/xattr.c:1910 ext4_xattr_move_to_block fs/ext4/xattr.c:2663 [inline] ext4_xattr_make_inode_space fs/ext4/xattr.c:2738 [inline] ext4_expand_extra_isize_ea+0xf57/0x1990 fs/ext4/xattr.c:2830 __ext4_expand_extra_isize+0x322/0x450 fs/ext4/inode.c:5782 ext4_try_to_expand_extra_isize fs/ext4/inode.c:5825 [inline] __ext4_mark_inode_dirty+0x55a/0x890 fs/ext4/inode.c:5903 ext4_setattr+0x1ada/0x2700 fs/ext4/inode.c:5413 notify_change+0x742/0x11f0 fs/attr.c:497 do_truncate+0x15c/0x220 fs/open.c:65 handle_truncate fs/namei.c:3308 [inline] do_open fs/namei.c:3654 [inline] path_openat+0x2505/0x29f0 fs/namei.c:3807 do_filp_open+0x1dc/0x430 fs/namei.c:3834 do_sys_openat2+0x17a/0x1e0 fs/open.c:1405 do_sys_open fs/open.c:1420 [inline] __do_sys_creat fs/open.c:1496 [inline] __se_sys_creat fs/open.c:1490 [inline] __ia32_sys_creat+0xcc/0x120 fs/open.c:1490 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #2 (&ei->i_data_sem){++++}-{3:3}: down_write+0x3a/0x50 kernel/locking/rwsem.c:1579 ext4_map_blocks+0x5ab/0x17d0 fs/ext4/inode.c:616 mpage_map_one_extent fs/ext4/inode.c:2163 [inline] mpage_map_and_submit_extent fs/ext4/inode.c:2216 [inline] ext4_do_writepages+0x172c/0x3250 fs/ext4/inode.c:2679 ext4_writepages+0x303/0x730 fs/ext4/inode.c:2768 do_writepages+0x1a3/0x7f0 mm/page-writeback.c:2634 __writeback_single_inode+0x163/0xf90 fs/fs-writeback.c:1651 writeback_sb_inodes+0x611/0x1150 fs/fs-writeback.c:1947 __writeback_inodes_wb+0xff/0x2e0 fs/fs-writeback.c:2018 wb_writeback+0x721/0xb50 fs/fs-writeback.c:2129 wb_check_background_flush fs/fs-writeback.c:2199 [inline] wb_do_writeback fs/fs-writeback.c:2287 [inline] wb_workfn+0x8c4/0xf40 fs/fs-writeback.c:2314 process_one_work+0x958/0x1ad0 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #1 (jbd2_handle){++++}-{0:0}: start_this_handle+0x1101/0x15e0 fs/jbd2/transaction.c:463 jbd2__journal_start+0x394/0x6a0 fs/jbd2/transaction.c:520 __ext4_journal_start_sb+0x358/0x660 fs/ext4/ext4_jbd2.c:112 ext4_sample_last_mounted fs/ext4/file.c:837 [inline] ext4_file_open+0x636/0xc90 fs/ext4/file.c:865 do_dentry_open+0x910/0x1930 fs/open.c:955 do_open fs/namei.c:3650 [inline] path_openat+0x1e3a/0x29f0 fs/namei.c:3807 do_filp_open+0x1dc/0x430 fs/namei.c:3834 do_sys_openat2+0x17a/0x1e0 fs/open.c:1405 do_sys_open fs/open.c:1420 [inline] __do_sys_openat fs/open.c:1436 [inline] __se_sys_openat fs/open.c:1431 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1431 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (sb_internal){.+.+}-{0:0}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1655 [inline] sb_start_intwrite include/linux/fs.h:1838 [inline] ext4_evict_inode+0xd7b/0x17d0 fs/ext4/inode.c:212 evict+0x2ed/0x6c0 fs/inode.c:667 iput_final fs/inode.c:1741 [inline] iput.part.0+0x5a8/0x7f0 fs/inode.c:1767 iput+0x5c/0x80 fs/inode.c:1757 dentry_unlink_inode+0x295/0x480 fs/dcache.c:400 __dentry_kill+0x1d0/0x600 fs/dcache.c:603 shrink_kill fs/dcache.c:1048 [inline] shrink_dentry_list+0x140/0x5d0 fs/dcache.c:1075 prune_dcache_sb+0xeb/0x150 fs/dcache.c:1156 super_cache_scan+0x32a/0x550 fs/super.c:221 do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435 shrink_slab_memcg mm/shrinker.c:548 [inline] shrink_slab+0xa87/0x1310 mm/shrinker.c:626 shrink_one+0x493/0x7c0 mm/vmscan.c:4790 shrink_many mm/vmscan.c:4851 [inline] lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4951 shrink_node mm/vmscan.c:5910 [inline] kswapd_shrink_node mm/vmscan.c:6720 [inline] balance_pgdat+0x1105/0x1970 mm/vmscan.c:6911 kswapd+0x5ea/0xbf0 mm/vmscan.c:7180 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 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: Chain exists of: sb_internal --> &ei->i_data_sem --> fs_reclaim Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&ei->i_data_sem); lock(fs_reclaim); rlock(sb_internal); *** DEADLOCK *** 2 locks held by kswapd0/112: #0: ffffffff8dd3ab20 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x166/0x1970 mm/vmscan.c:6798 #1: ffff888026fda0e0 (&type->s_umount_key#33){++++}-{3:3}, at: super_trylock_shared fs/super.c:562 [inline] #1: ffff888026fda0e0 (&type->s_umount_key#33){++++}-{3:3}, at: super_cache_scan+0x96/0x550 fs/super.c:196 stack backtrace: CPU: 1 PID: 112 Comm: kswapd0 Not tainted 6.10.0-rc5-syzkaller-00018-g55027e689933 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 check_noncircular+0x31a/0x400 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 kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1655 [inline] sb_start_intwrite include/linux/fs.h:1838 [inline] ext4_evict_inode+0xd7b/0x17d0 fs/ext4/inode.c:212 evict+0x2ed/0x6c0 fs/inode.c:667 iput_final fs/inode.c:1741 [inline] iput.part.0+0x5a8/0x7f0 fs/inode.c:1767 iput+0x5c/0x80 fs/inode.c:1757 dentry_unlink_inode+0x295/0x480 fs/dcache.c:400 __dentry_kill+0x1d0/0x600 fs/dcache.c:603 shrink_kill fs/dcache.c:1048 [inline] shrink_dentry_list+0x140/0x5d0 fs/dcache.c:1075 prune_dcache_sb+0xeb/0x150 fs/dcache.c:1156 super_cache_scan+0x32a/0x550 fs/super.c:221 do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435 shrink_slab_memcg mm/shrinker.c:548 [inline] shrink_slab+0xa87/0x1310 mm/shrinker.c:626 shrink_one+0x493/0x7c0 mm/vmscan.c:4790 shrink_many mm/vmscan.c:4851 [inline] lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4951 shrink_node mm/vmscan.c:5910 [inline] kswapd_shrink_node mm/vmscan.c:6720 [inline] balance_pgdat+0x1105/0x1970 mm/vmscan.c:6911 kswapd+0x5ea/0xbf0 mm/vmscan.c:7180 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244