binder: send failed reply for transaction 521 to 7328:7329
binder: undelivered TRANSACTION_COMPLETE
binder: undelivered TRANSACTION_ERROR: 29189

===============================
[ INFO: suspicious RCU usage. ]
4.9.111-g03c70fe #58 Not tainted
-------------------------------
kernel/rcu/tree_plugin.h:678 Illegal synchronize_rcu() in RCU read-side critical section!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 0
3 locks held by syz-executor6/7312:
 #0:  (sb_writers#3){.+.+.+}, at: [<ffffffff81575a28>] file_start_write include/linux/fs.h:2640 [inline]
 #0:  (sb_writers#3){.+.+.+}, at: [<ffffffff81575a28>] do_sendfile+0x918/0xc60 fs/read_write.c:1392
 #1:  (rcu_read_lock){......}, at: [<ffffffff81438b80>] find_get_entry+0x0/0x540 include/linux/compiler.h:243
 #2:  (rcu_callback){......}, at: [<ffffffff8128784e>] __rcu_reclaim kernel/rcu/rcu.h:108 [inline]
 #2:  (rcu_callback){......}, at: [<ffffffff8128784e>] rcu_do_batch kernel/rcu/tree.c:2789 [inline]
 #2:  (rcu_callback){......}, at: [<ffffffff8128784e>] invoke_rcu_callbacks kernel/rcu/tree.c:3053 [inline]
 #2:  (rcu_callback){......}, at: [<ffffffff8128784e>] __rcu_process_callbacks kernel/rcu/tree.c:3020 [inline]
 #2:  (rcu_callback){......}, at: [<ffffffff8128784e>] rcu_process_callbacks+0x98e/0x12b0 kernel/rcu/tree.c:3037

stack backtrace:
CPU: 1 PID: 7312 Comm: syz-executor6 Not tainted 4.9.111-g03c70fe #58
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801db307d60 ffffffff81eb2729 ffff8801b9b64800 0000000000000000
 0000000000000002 ffffffff83c6df20 ffff8801c1d6f7d8 ffff8801db307d90
 ffffffff81426090 ffff8801c1d6f680 ffff8801d69c8848 ffff8801d69c8048
Call Trace:
 <IRQ> [  629.364961]  [<ffffffff81eb2729>] __dump_stack lib/dump_stack.c:15 [inline]
 <IRQ> [  629.364961]  [<ffffffff81eb2729>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81426090>] lockdep_rcu_suspicious.cold.48+0x110/0x141 kernel/locking/lockdep.c:4455
 [<ffffffff812840e8>] synchronize_rcu+0x68/0x90 kernel/rcu/tree_plugin.h:675
 [<ffffffff836bbeda>] __l2tp_session_unhash+0x38a/0x520 net/l2tp/l2tp_core.c:1796
 [<ffffffff836bc267>] l2tp_tunnel_closeall+0x1f7/0x350 net/l2tp/l2tp_core.c:1364
 [<ffffffff836bcb22>] l2tp_tunnel_destruct+0x2f2/0x590 net/l2tp/l2tp_core.c:1324
 [<ffffffff83020095>] __sk_destruct+0x55/0x590 net/core/sock.c:1428
 [<ffffffff8128776e>] __rcu_reclaim kernel/rcu/rcu.h:118 [inline]
 [<ffffffff8128776e>] rcu_do_batch kernel/rcu/tree.c:2789 [inline]
 [<ffffffff8128776e>] invoke_rcu_callbacks kernel/rcu/tree.c:3053 [inline]
 [<ffffffff8128776e>] __rcu_process_callbacks kernel/rcu/tree.c:3020 [inline]
 [<ffffffff8128776e>] rcu_process_callbacks+0x8ae/0x12b0 kernel/rcu/tree.c:3037
 [<ffffffff839ff8bb>] __do_softirq+0x20b/0x937 kernel/softirq.c:284
 [<ffffffff8114b237>] invoke_softirq kernel/softirq.c:364 [inline]
 [<ffffffff8114b237>] irq_exit+0x147/0x190 kernel/softirq.c:405
 [<ffffffff839fe4a1>] exiting_irq arch/x86/include/asm/apic.h:659 [inline]
 [<ffffffff839fe4a1>] smp_apic_timer_interrupt+0x81/0xa0 arch/x86/kernel/apic/apic.c:960
 [<ffffffff839fa630>] apic_timer_interrupt+0xa0/0xb0 arch/x86/entry/entry_64.S:648
 <EOI> [  629.478580]  [<ffffffff81438c47>] ? radix_tree_deref_slot include/linux/radix-tree.h:199 [inline]
 <EOI> [  629.478580]  [<ffffffff81438c47>] ? find_get_entry+0xc7/0x540 mm/filemap.c:1097
 [<ffffffff81439ffb>] pagecache_get_page+0x4b/0x720 mm/filemap.c:1203
 [<ffffffff8143e846>] find_get_page include/linux/pagemap.h:258 [inline]
 [<ffffffff8143e846>] do_generic_file_read mm/filemap.c:1713 [inline]
 [<ffffffff8143e846>] generic_file_read_iter+0x696/0x1a90 mm/filemap.c:1971
 [<ffffffff816150d9>] generic_file_splice_read+0x2c9/0x4f0 fs/splice.c:309
 [<ffffffff8161382c>] do_splice_to+0x10c/0x170 fs/splice.c:899
 [<ffffffff81613acf>] splice_direct_to_actor+0x23f/0x7e0 fs/splice.c:971
 [<ffffffff81614213>] do_splice_direct+0x1a3/0x270 fs/splice.c:1080
 [<ffffffff81575600>] do_sendfile+0x4f0/0xc60 fs/read_write.c:1393
 [<ffffffff81577681>] SYSC_sendfile64 fs/read_write.c:1448 [inline]
 [<ffffffff81577681>] SyS_sendfile64+0xd1/0x160 fs/read_write.c:1440
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839f8cd3>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
ODEBUG: object ffff8801db307ce8 is NOT on stack ffff8801a93f0000, but annotated
------------[ cut here ]------------
WARNING: CPU: 1 PID: 7312 at lib/debugobjects.c:303 debug_object_is_on_stack lib/debugobjects.c:303 [inline]
WARNING: CPU: 1 PID: 7312 at lib/debugobjects.c:303 __debug_object_init.cold.10+0x6b/0x2b0 lib/debugobjects.c:329