INFO: task syz-executor.3:4950 blocked for more than 143 seconds. Not tainted 5.4.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D23624 4950 18463 0x00004004 Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x837/0xc50 kernel/sched/core.c:4081 schedule+0x181/0x210 kernel/sched/core.c:4155 io_schedule+0x8b/0x100 kernel/sched/core.c:5799 wait_on_page_bit_common+0x918/0xc90 mm/filemap.c:1175 wait_on_page_bit+0x46/0x50 mm/filemap.c:1224 wait_on_page_writeback+0x13e/0x180 mm/page-writeback.c:2822 __filemap_fdatawait_range+0x1b5/0x3b0 mm/filemap.c:526 file_write_and_wait_range+0x141/0x1a0 mm/filemap.c:786 __generic_file_fsync+0x76/0x1a0 fs/libfs.c:1000 fat_file_fsync+0x7c/0x190 fs/fat/file.c:199 vfs_fsync_range+0xfd/0x1a0 fs/sync.c:197 generic_write_sync include/linux/fs.h:2849 [inline] generic_file_write_iter+0x575/0x630 mm/filemap.c:3470 do_iter_readv_writev+0x651/0x8e0 include/linux/fs.h:1889 do_iter_write+0x180/0x590 fs/read_write.c:970 vfs_iter_write+0x7c/0xa0 fs/read_write.c:983 iter_file_splice_write+0x6d8/0xe20 fs/splice.c:746 do_splice_from fs/splice.c:848 [inline] direct_splice_actor+0xf7/0x130 fs/splice.c:1020 splice_direct_to_actor+0x463/0xac0 fs/splice.c:975 do_splice_direct+0x200/0x330 fs/splice.c:1063 do_sendfile+0x7e4/0xfd0 fs/read_write.c:1464 __do_sys_sendfile64 fs/read_write.c:1519 [inline] __se_sys_sendfile64 fs/read_write.c:1511 [inline] __x64_sys_sendfile64+0xfc/0x1b0 fs/read_write.c:1511 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a679 Code: f3 a4 48 8b 94 24 18 10 00 00 ff 12 48 8b 94 24 10 10 00 00 48 8b bc 24 20 10 00 00 8b 8c 24 28 10 00 00 8b 9c 24 2c 10 00 00 <48> 89 e6 48 01 df 48 01 de 48 29 d9 e8 c6 fa ff ff 48 8b ac 24 00 RSP: 002b:00007f46497bec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000000045a679 RDX: 0000000020000000 RSI: 0000000000000004 RDI: 0000000000000004 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 00008080fffffffe R11: 0000000000000246 R12: 00007f46497bf6d4 R13: 00000000004c8623 R14: 00000000004df300 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1080: #0: ffffffff88ad42c0 (rcu_read_lock){....}, at: rcu_lock_acquire+0x4/0x30 include/linux/rcupdate.h:207 2 locks held by getty/7933: #0: ffff8880a944b090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272 #1: ffffc90005f212e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156 2 locks held by getty/7934: #0: ffff88809a5b9090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272 #1: ffffc90005f252e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156 2 locks held by getty/7935: #0: ffff8880a74c5090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272 #1: ffffc90005f312e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156 2 locks held by getty/7936: #0: ffff888095ccb090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272 #1: ffffc90005f292e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156 2 locks held by getty/7937: #0: ffff888099faa090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272 #1: ffffc90005f192e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156 2 locks held by getty/7938: #0: ffff88808efab090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272 #1: ffffc90005f1d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156 2 locks held by getty/7939: #0: ffff8880a1af7090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272 #1: ffffc90005f012e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.3/4950: #0: ffff8880a8964428 (sb_writers#14){.+.+}, at: file_start_write include/linux/fs.h:2878 [inline] #0: ffff8880a8964428 (sb_writers#14){.+.+}, at: do_sendfile+0x7c2/0xfd0 fs/read_write.c:1463 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1080 Comm: khungtaskd Not tainted 5.4.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fb/0x318 lib/dump_stack.c:118 nmi_cpu_backtrace+0xaf/0x1a0 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x174/0x290 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace+0x17/0x20 include/linux/nmi.h:146 check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xd49/0xd60 kernel/hung_task.c:289 kthread+0x332/0x350 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 312 Comm: kworker/u4:4 Not tainted 5.4.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet RIP: 0010:check_memory_region+0x6/0x2e0 mm/kasan/generic.c:191 Code: 0c 31 db 48 c7 c7 c4 a0 5a 88 4c 89 fe 31 c0 e8 93 cd ae ff eb cf cc cc cc cc cc cc cc cc cc cc cc cc cc cc 55 48 89 e5 41 57 <41> 56 41 55 41 54 53 b0 01 48 85 f6 0f 84 fd 01 00 00 48 89 fb 48 RSP: 0018:ffff8880a8e0f948 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000029 RCX: ffffffff8159d3dc RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff897e8ca0 RBP: ffff8880a8e0f950 R08: dffffc0000000000 R09: fffffbfff12fd195 R10: fffffbfff12fd195 R11: 0000000000000000 R12: ffff8880a8e00df4 R13: ffff8880a8e00d50 R14: ffff8880a8e00dd0 R15: ffff8880a8e004c0 FS: 0000000000000000(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000000a453e000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __kasan_check_read+0x11/0x20 mm/kasan/common.c:92 test_bit include/asm-generic/bitops-instrumented.h:237 [inline] __lock_acquire+0x6fc/0x1be0 kernel/locking/lockdep.c:3925 lock_acquire+0x158/0x250 kernel/locking/lockdep.c:4485 rcu_lock_acquire+0x2e/0x40 include/linux/rcupdate.h:208 rcu_read_lock include/linux/rcupdate.h:617 [inline] batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:754 [inline] batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:821 [inline] batadv_iv_ogm_schedule+0x396/0xf10 net/batman-adv/bat_iv_ogm.c:865 batadv_iv_send_outstanding_bat_ogm_packet+0x665/0x770 net/batman-adv/bat_iv_ogm.c:1718 process_one_work+0x7ef/0x10d0 kernel/workqueue.c:2264 worker_thread+0xc01/0x1630 kernel/workqueue.c:2410 kthread+0x332/0x350 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352