====================================================== WARNING: possible circular locking dependency detected 6.2.0-rc6-syzkaller-00050-g9f266ccaa2f5 #0 Not tainted ------------------------------------------------------ kthreadd/2 is trying to acquire lock: ffff8880253fd090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x79/0x100 fs/reiserfs/lock.c:27 but task is already holding lock: ffffffff8c8cef00 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4747 [inline] ffffffff8c8cef00 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4772 [inline] ffffffff8c8cef00 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath.constprop.0+0x808/0x23d0 mm/page_alloc.c:5178 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (fs_reclaim){+.+.}-{0:0}: __fs_reclaim_acquire mm/page_alloc.c:4674 [inline] fs_reclaim_acquire+0x11d/0x160 mm/page_alloc.c:4688 might_alloc include/linux/sched/mm.h:271 [inline] slab_pre_alloc_hook mm/slab.h:720 [inline] slab_alloc_node mm/slab.c:3247 [inline] slab_alloc mm/slab.c:3272 [inline] __kmem_cache_alloc_lru mm/slab.c:3449 [inline] kmem_cache_alloc_lru+0x3e/0x7b0 mm/slab.c:3465 __d_alloc+0x32/0x980 fs/dcache.c:1769 d_alloc_anon fs/dcache.c:1868 [inline] d_make_root+0x49/0x110 fs/dcache.c:2069 reiserfs_fill_super+0x12eb/0x2e90 fs/reiserfs/super.c:2083 mount_bdev+0x351/0x410 fs/super.c:1359 legacy_get_tree+0x109/0x220 fs/fs_context.c:610 vfs_get_tree+0x8d/0x2f0 fs/super.c:1489 do_new_mount fs/namespace.c:3145 [inline] path_mount+0x132a/0x1e20 fs/namespace.c:3475 do_mount fs/namespace.c:3488 [inline] __do_sys_mount fs/namespace.c:3697 [inline] __se_sys_mount fs/namespace.c:3674 [inline] __x64_sys_mount+0x283/0x300 fs/namespace.c:3674 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (&sbi->lock){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5055 lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12f/0x1360 kernel/locking/mutex.c:747 reiserfs_write_lock+0x79/0x100 fs/reiserfs/lock.c:27 reiserfs_evict_inode+0x30b/0x540 fs/reiserfs/inode.c:55 evict+0x2ed/0x6b0 fs/inode.c:664 iput_final fs/inode.c:1747 [inline] iput.part.0+0x59b/0x880 fs/inode.c:1773 iput+0x5c/0x80 fs/inode.c:1763 dentry_unlink_inode+0x2b1/0x460 fs/dcache.c:401 __dentry_kill+0x3c0/0x640 fs/dcache.c:607 shrink_dentry_list+0x240/0x800 fs/dcache.c:1201 prune_dcache_sb+0xeb/0x150 fs/dcache.c:1282 super_cache_scan+0x33a/0x590 fs/super.c:104 do_shrink_slab+0x464/0xce0 mm/vmscan.c:843 shrink_slab_memcg mm/vmscan.c:912 [inline] shrink_slab+0x388/0x660 mm/vmscan.c:991 shrink_node_memcgs mm/vmscan.c:6140 [inline] shrink_node+0x95d/0x1f40 mm/vmscan.c:6169 shrink_zones mm/vmscan.c:6407 [inline] do_try_to_free_pages+0x3b4/0x17a0 mm/vmscan.c:6469 try_to_free_pages+0x2e5/0x960 mm/vmscan.c:6704 __perform_reclaim mm/page_alloc.c:4750 [inline] __alloc_pages_direct_reclaim mm/page_alloc.c:4772 [inline] __alloc_pages_slowpath.constprop.0+0x8b6/0x23d0 mm/page_alloc.c:5178 __alloc_pages+0x4aa/0x5b0 mm/page_alloc.c:5562 __alloc_pages_node include/linux/gfp.h:237 [inline] kmem_getpages mm/slab.c:1363 [inline] cache_grow_begin+0x94/0x390 mm/slab.c:2576 fallback_alloc+0x1e2/0x2d0 mm/slab.c:3119 __do_cache_alloc mm/slab.c:3223 [inline] slab_alloc_node mm/slab.c:3256 [inline] kmem_cache_alloc_node+0x181/0x590 mm/slab.c:3534 alloc_task_struct_node kernel/fork.c:171 [inline] dup_task_struct kernel/fork.c:979 [inline] copy_process+0x3aa/0x7520 kernel/fork.c:2097 kernel_clone+0xeb/0x990 kernel/fork.c:2681 kernel_thread+0xb9/0xf0 kernel/fork.c:2741 create_kthread kernel/kthread.c:399 [inline] kthreadd+0x4f2/0x750 kernel/kthread.c:746 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&sbi->lock); lock(fs_reclaim); lock(&sbi->lock); *** DEADLOCK *** 3 locks held by kthreadd/2: #0: ffffffff8c8cef00 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4747 [inline] #0: ffffffff8c8cef00 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4772 [inline] #0: ffffffff8c8cef00 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath.constprop.0+0x808/0x23d0 mm/page_alloc.c:5178 #1: ffffffff8c88caf0 (shrinker_rwsem){++++}-{3:3}, at: shrink_slab_memcg mm/vmscan.c:885 [inline] #1: ffffffff8c88caf0 (shrinker_rwsem){++++}-{3:3}, at: shrink_slab+0x2a0/0x660 mm/vmscan.c:991 #2: ffff88801ade80e0 (&type->s_umount_key#68){.+.+}-{3:3}, at: trylock_super fs/super.c:415 [inline] #2: ffff88801ade80e0 (&type->s_umount_key#68){.+.+}-{3:3}, at: super_cache_scan+0x70/0x590 fs/super.c:79 stack backtrace: CPU: 1 PID: 2 Comm: kthreadd Not tainted 6.2.0-rc6-syzkaller-00050-g9f266ccaa2f5 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2177 check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5055 lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12f/0x1360 kernel/locking/mutex.c:747 reiserfs_write_lock+0x79/0x100 fs/reiserfs/lock.c:27 reiserfs_evict_inode+0x30b/0x540 fs/reiserfs/inode.c:55 evict+0x2ed/0x6b0 fs/inode.c:664 iput_final fs/inode.c:1747 [inline] iput.part.0+0x59b/0x880 fs/inode.c:1773 iput+0x5c/0x80 fs/inode.c:1763 dentry_unlink_inode+0x2b1/0x460 fs/dcache.c:401 __dentry_kill+0x3c0/0x640 fs/dcache.c:607 shrink_dentry_list+0x240/0x800 fs/dcache.c:1201 prune_dcache_sb+0xeb/0x150 fs/dcache.c:1282 super_cache_scan+0x33a/0x590 fs/super.c:104 do_shrink_slab+0x464/0xce0 mm/vmscan.c:843 shrink_slab_memcg mm/vmscan.c:912 [inline] shrink_slab+0x388/0x660 mm/vmscan.c:991 shrink_node_memcgs mm/vmscan.c:6140 [inline] shrink_node+0x95d/0x1f40 mm/vmscan.c:6169 shrink_zones mm/vmscan.c:6407 [inline] do_try_to_free_pages+0x3b4/0x17a0 mm/vmscan.c:6469 try_to_free_pages+0x2e5/0x960 mm/vmscan.c:6704 __perform_reclaim mm/page_alloc.c:4750 [inline] __alloc_pages_direct_reclaim mm/page_alloc.c:4772 [inline] __alloc_pages_slowpath.constprop.0+0x8b6/0x23d0 mm/page_alloc.c:5178 __alloc_pages+0x4aa/0x5b0 mm/page_alloc.c:5562 __alloc_pages_node include/linux/gfp.h:237 [inline] kmem_getpages mm/slab.c:1363 [inline] cache_grow_begin+0x94/0x390 mm/slab.c:2576 fallback_alloc+0x1e2/0x2d0 mm/slab.c:3119 __do_cache_alloc mm/slab.c:3223 [inline] slab_alloc_node mm/slab.c:3256 [inline] kmem_cache_alloc_node+0x181/0x590 mm/slab.c:3534 alloc_task_struct_node kernel/fork.c:171 [inline] dup_task_struct kernel/fork.c:979 [inline] copy_process+0x3aa/0x7520 kernel/fork.c:2097 kernel_clone+0xeb/0x990 kernel/fork.c:2681 kernel_thread+0xb9/0xf0 kernel/fork.c:2741 create_kthread kernel/kthread.c:399 [inline] kthreadd+0x4f2/0x750 kernel/kthread.c:746 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308