=============================== [ INFO: suspicious RCU usage. ] 4.9.202+ #0 Not tainted ------------------------------- include/linux/radix-tree.h:199 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 0 2 locks held by syz-executor184/2062: #0: (&sb->s_type->i_mutex_key#10){+.+.+.}, at: [<00000000e5465ac4>] inode_lock include/linux/fs.h:771 [inline] #0: (&sb->s_type->i_mutex_key#10){+.+.+.}, at: [<00000000e5465ac4>] shmem_add_seals+0x166/0x1020 mm/shmem.c:2610 #1: (&(&mapping->tree_lock)->rlock){..-...}, at: [<000000008749736d>] spin_lock_irq include/linux/spinlock.h:332 [inline] #1: (&(&mapping->tree_lock)->rlock){..-...}, at: [<000000008749736d>] shmem_tag_pins mm/shmem.c:2465 [inline] #1: (&(&mapping->tree_lock)->rlock){..-...}, at: [<000000008749736d>] shmem_wait_for_pins mm/shmem.c:2506 [inline] #1: (&(&mapping->tree_lock)->rlock){..-...}, at: [<000000008749736d>] shmem_add_seals+0x342/0x1020 mm/shmem.c:2622 stack backtrace: CPU: 1 PID: 2062 Comm: syz-executor184 Not tainted 4.9.202+ #0 ffff8801cf257ca0 ffffffff81b55d2b ffff8801c977ec28 0000000000000000 0000000000000002 00000000000000c7 ffff8801d209df00 ffff8801cf257cd0 ffffffff81406867 ffffea00074d45c0 dffffc0000000000 ffff8801cf257d78 Call Trace: [<000000000d8f2bba>] __dump_stack lib/dump_stack.c:15 [inline] [<000000000d8f2bba>] dump_stack+0xcb/0x130 lib/dump_stack.c:56 [<00000000ff27527b>] lockdep_rcu_suspicious.cold+0x10a/0x149 kernel/locking/lockdep.c:4458 [<0000000019b3d172>] radix_tree_deref_slot include/linux/radix-tree.h:199 [inline] [<0000000019b3d172>] shmem_tag_pins mm/shmem.c:2467 [inline] [<0000000019b3d172>] shmem_wait_for_pins mm/shmem.c:2506 [inline] [<0000000019b3d172>] shmem_add_seals+0xa44/0x1020 mm/shmem.c:2622 [<000000003a7a5a43>] shmem_fcntl+0xf7/0x130 mm/shmem.c:2657 [<0000000