====================================================== WARNING: possible circular locking dependency detected 6.13.0-rc6-next-20250107-syzkaller #0 Not tainted ------------------------------------------------------ syz.3.1239/7271 is trying to acquire lock: ffff888022f5c848 (vm_lock){++++}-{0:0}, at: binder_alloc_free_page+0x150/0xd50 drivers/android/binder_alloc.c:1156 but task is already holding lock: ffff8880306d3430 (&l->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline] ffff8880306d3430 (&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: -> #3 (&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 -> #2 (&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] __mark_inode_dirty+0x3ff/0xe90 fs/fs-writeback.c:2540 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 iter_file_splice_write+0xbfa/0x1510 fs/splice.c:743 do_splice_from fs/splice.c:941 [inline] direct_splice_actor+0x11b/0x220 fs/splice.c:1164 splice_direct_to_actor+0x586/0xc80 fs/splice.c:1108 do_splice_direct_actor fs/splice.c:1207 [inline] do_splice_direct+0x289/0x3e0 fs/splice.c:1233 do_sendfile+0x564/0x8a0 fs/read_write.c:1363 __do_sys_sendfile64 fs/read_write.c:1418 [inline] __se_sys_sendfile64+0x100/0x1e0 fs/read_write.c:1410 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 *** 3 locks held by syz.3.1239/7271: #0: ffff88807ab3c420 (sb_writers#3){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x220 fs/splice.c:1163 #1: ffff8880306d3430 (&l->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline] #1: ffff8880306d3430 (&l->lock){+.+.}-{3:3}, at: lock_list_lru_of_memcg+0x24c/0x4d0 mm/list_lru.c:77 #2: ffffffff8e937ee0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #2: ffffffff8e937ee0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #2: ffffffff8e937ee0 (rcu_read_lock){....}-{1:3}, at: lock_vma_under_rcu+0x1dd/0x9a0 mm/memory.c:6431 stack backtrace: CPU: 1 UID: 0 PID: 7271 Comm: syz.3.1239 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 iter_file_splice_write+0xbfa/0x1510 fs/splice.c:743 do_splice_from fs/splice.c:941 [inline] direct_splice_actor+0x11b/0x220 fs/splice.c:1164 splice_direct_to_actor+0x586/0xc80 fs/splice.c:1108 do_splice_direct_actor fs/splice.c:1207 [inline] do_splice_direct+0x289/0x3e0 fs/splice.c:1233 do_sendfile+0x564/0x8a0 fs/read_write.c:1363 __do_sys_sendfile64 fs/read_write.c:1418 [inline] __se_sys_sendfile64+0x100/0x1e0 fs/read_write.c:1410 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: 0033:0x7fb117b85d29 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:00007ffd1b9edab8 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007fb117d75fa0 RCX: 00007fb117b85d29 RDX: 0000000020002080 RSI: 0000000000000006 RDI: 0000000000000007 RBP: 00007fb117c01b08 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000023b R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb117d75fa0 R14: 00007fb117d75fa0 R15: 000000000000113a syz.3.1239 (7271): drop_caches: 2 syz.3.1239 (7271): drop_caches: 2