====================================================== WARNING: possible circular locking dependency detected 6.13.0-rc6-next-20250107-syzkaller #0 Not tainted ------------------------------------------------------ syz.0.37/6046 is trying to acquire lock: ffff888033794c08 (vm_lock){++++}-{0:0}, at: binder_alloc_free_page+0x150/0xd50 drivers/android/binder_alloc.c:1156 but task is already holding lock: ffff88814c50c230 (&l->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline] ffff88814c50c230 (&l->lock){+.+.}-{3:3}, at: lock_list_lru_of_memcg+0x24c/0x4d0 mm/list_lru.c:77 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&l->lock){+.+.}-{3:3}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] lock_list_lru_of_memcg+0x24c/0x4d0 mm/list_lru.c:77 list_lru_add+0x59/0x270 mm/list_lru.c:163 list_lru_add_obj+0x17b/0x250 mm/list_lru.c:186 __inode_add_lru fs/inode.c:534 [inline] iput_final fs/inode.c:1923 [inline] iput+0x89c/0xa50 fs/inode.c:1972 __dentry_kill+0x20d/0x630 fs/dcache.c:625 shrink_kill+0xa9/0x2c0 fs/dcache.c:1070 shrink_dentry_list+0x2c0/0x5b0 fs/dcache.c:1097 shrink_dcache_sb+0x25e/0x3e0 fs/dcache.c:1217 reconfigure_super+0x2c6/0x870 fs/super.c:1061 do_remount fs/namespace.c:3100 [inline] path_mount+0xc22/0xfa0 fs/namespace.c:3879 do_mount fs/namespace.c:3900 [inline] __do_sys_mount fs/namespace.c:4111 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4088 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #3 (&sb->s_type->i_lock_key#23){+.+.}-{3:3}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] d_instantiate_new+0x76/0x130 fs/dcache.c:1922 ext4_add_nondir+0x21e/0x290 fs/ext4/namei.c:2808 ext4_create+0x377/0x550 fs/ext4/namei.c:2849 lookup_open fs/namei.c:3649 [inline] open_last_lookups fs/namei.c:3748 [inline] path_openat+0x192f/0x3580 fs/namei.c:3984 do_filp_open+0x27f/0x4e0 fs/namei.c:4014 do_sys_openat2+0x13e/0x1d0 fs/open.c:1427 do_sys_open fs/open.c:1442 [inline] __do_sys_openat fs/open.c:1458 [inline] __se_sys_openat fs/open.c:1453 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1453 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #2 (jbd2_handle){++++}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 start_this_handle+0x1eb4/0x2110 fs/jbd2/transaction.c:448 jbd2__journal_start+0x2da/0x5d0 fs/jbd2/transaction.c:505 __ext4_journal_start_sb+0x239/0x600 fs/ext4/ext4_jbd2.c:112 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline] ext4_dirty_inode+0x92/0x110 fs/ext4/inode.c:6039 __mark_inode_dirty+0x2ee/0xe90 fs/fs-writeback.c:2515 generic_update_time fs/inode.c:2112 [inline] inode_update_time fs/inode.c:2125 [inline] __file_update_time fs/inode.c:2353 [inline] file_update_time+0x3d2/0x450 fs/inode.c:2383 ext4_page_mkwrite+0x210/0x1100 fs/ext4/inode.c:6160 do_page_mkwrite+0x159/0x340 mm/memory.c:3244 wp_page_shared mm/memory.c:3645 [inline] do_wp_page+0x23cd/0x49b0 mm/memory.c:3795 handle_pte_fault mm/memory.c:5905 [inline] __handle_mm_fault+0x24cf/0x70f0 mm/memory.c:6032 handle_mm_fault+0x3e2/0x8c0 mm/memory.c:6201 do_user_addr_fault arch/x86/mm/fault.c:1337 [inline] handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x459/0x8b0 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 -> #1 (sb_pagefaults){.+.+}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 percpu_down_read+0x44/0x1b0 include/linux/percpu-rwsem.h:51 __sb_start_write include/linux/fs.h:1773 [inline] sb_start_pagefault include/linux/fs.h:1938 [inline] ext4_page_mkwrite+0x1f9/0x1100 fs/ext4/inode.c:6159 do_page_mkwrite+0x159/0x340 mm/memory.c:3244 wp_page_shared mm/memory.c:3645 [inline] do_wp_page+0x23cd/0x49b0 mm/memory.c:3795 handle_pte_fault mm/memory.c:5905 [inline] __handle_mm_fault+0x24cf/0x70f0 mm/memory.c:6032 handle_mm_fault+0x3e2/0x8c0 mm/memory.c:6201 do_user_addr_fault arch/x86/mm/fault.c:1337 [inline] handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x459/0x8b0 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 -> #0 (vm_lock){++++}-{0:0}: check_prev_add kernel/locking/lockdep.c:3163 [inline] check_prevs_add kernel/locking/lockdep.c:3282 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 vma_start_read include/linux/mm.h:749 [inline] lock_vma_under_rcu+0x35f/0x9a0 mm/memory.c:6436 binder_alloc_free_page+0x150/0xd50 drivers/android/binder_alloc.c:1156 __list_lru_walk_one+0x170/0x470 mm/list_lru.c:300 list_lru_walk_one mm/list_lru.c:337 [inline] list_lru_walk_node+0xc4/0xa70 mm/list_lru.c:357 list_lru_walk include/linux/list_lru.h:282 [inline] binder_shrink_scan+0x138/0x260 drivers/android/binder_alloc.c:1226 do_shrink_slab+0x72d/0x1160 mm/shrinker.c:437 shrink_slab+0x1093/0x14d0 mm/shrinker.c:664 drop_slab_node mm/vmscan.c:421 [inline] drop_slab+0x142/0x280 mm/vmscan.c:439 drop_caches_sysctl_handler+0xbc/0x160 fs/drop_caches.c:68 proc_sys_call_handler+0x5ec/0x920 fs/proc/proc_sysctl.c:601 do_iter_readv_writev+0x71a/0x9d0 vfs_writev+0x38b/0xbc0 fs/read_write.c:1050 do_writev+0x1b6/0x360 fs/read_write.c:1096 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: vm_lock --> &sb->s_type->i_lock_key#23 --> &l->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&l->lock); lock(&sb->s_type->i_lock_key#23); lock(&l->lock); rlock(vm_lock); *** DEADLOCK *** 4 locks held by syz.0.37/6046: #0: ffff888028632ef8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x254/0x320 fs/file.c:1192 #1: ffff888029080420 (sb_writers#3){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3016 [inline] #1: ffff888029080420 (sb_writers#3){.+.+}-{0:0}, at: vfs_writev+0x2d6/0xbc0 fs/read_write.c:1048 #2: ffff88814c50c230 (&l->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline] #2: ffff88814c50c230 (&l->lock){+.+.}-{3:3}, at: lock_list_lru_of_memcg+0x24c/0x4d0 mm/list_lru.c:77 #3: ffffffff8e937ee0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #3: ffffffff8e937ee0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #3: ffffffff8e937ee0 (rcu_read_lock){....}-{1:3}, at: lock_vma_under_rcu+0x1dd/0x9a0 mm/memory.c:6431 stack backtrace: CPU: 0 UID: 0 PID: 6046 Comm: syz.0.37 Not tainted 6.13.0-rc6-next-20250107-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2076 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2208 check_prev_add kernel/locking/lockdep.c:3163 [inline] check_prevs_add kernel/locking/lockdep.c:3282 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 vma_start_read include/linux/mm.h:749 [inline] lock_vma_under_rcu+0x35f/0x9a0 mm/memory.c:6436 binder_alloc_free_page+0x150/0xd50 drivers/android/binder_alloc.c:1156 __list_lru_walk_one+0x170/0x470 mm/list_lru.c:300 list_lru_walk_one mm/list_lru.c:337 [inline] list_lru_walk_node+0xc4/0xa70 mm/list_lru.c:357 list_lru_walk include/linux/list_lru.h:282 [inline] binder_shrink_scan+0x138/0x260 drivers/android/binder_alloc.c:1226 do_shrink_slab+0x72d/0x1160 mm/shrinker.c:437 shrink_slab+0x1093/0x14d0 mm/shrinker.c:664 drop_slab_node mm/vmscan.c:421 [inline] drop_slab+0x142/0x280 mm/vmscan.c:439 drop_caches_sysctl_handler+0xbc/0x160 fs/drop_caches.c:68 proc_sys_call_handler+0x5ec/0x920 fs/proc/proc_sysctl.c:601 do_iter_readv_writev+0x71a/0x9d0 vfs_writev+0x38b/0xbc0 fs/read_write.c:1050 do_writev+0x1b6/0x360 fs/read_write.c:1096 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f94e8585d29 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f94e946c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 00007f94e8775fa0 RCX: 00007f94e8585d29 RDX: 0000000000000001 RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 00007f94e8601b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f94e8775fa0 R15: 00007fff730b4ba8 syz.0.37 (6046): drop_caches: 2