INFO: task syz-executor.3:2367 blocked for more than 143 seconds. Not tainted 5.4.0-rc8-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D23736 2367 7908 0x00004004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x7b7/0xc30 kernel/sched/core.c:4078 schedule+0x131/0x1e0 kernel/sched/core.c:4145 io_schedule+0x8b/0x100 kernel/sched/core.c:5789 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:2853 [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:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a639 Code: Bad RIP value. RSP: 002b:00007fef330fac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000000045a639 RDX: 0000000020000000 RSI: 0000000000000004 RDI: 0000000000000004 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 00008080fffffffe R11: 0000000000000246 R12: 00007fef330fb6d4 R13: 00000000004c83bf R14: 00000000004de7f0 R15: 00000000ffffffff INFO: task syz-executor.2:2393 blocked for more than 143 seconds. Not tainted 5.4.0-rc8-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D23800 2393 7906 0x00004004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x7b7/0xc30 kernel/sched/core.c:4078 schedule+0x131/0x1e0 kernel/sched/core.c:4145 io_schedule+0x8b/0x100 kernel/sched/core.c:5789 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:2853 [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:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a639 Code: Bad RIP value. RSP: 002b:00007f2eac5d9c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000000045a639 RDX: 0000000020000000 RSI: 0000000000000004 RDI: 0000000000000004 RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000 R10: 00008080fffffffe R11: 0000000000000246 R12: 00007f2eac5da6d4 R13: 00000000004c83bf R14: 00000000004de7f0 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1067: #0: ffffffff888d3e40 (rcu_read_lock){....}, at: rcu_lock_acquire+0x4/0x30 include/linux/rcupdate.h:207 1 lock held by rsyslogd/7771: #0: ffff8880980e2da0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x243/0x2e0 fs/file.c:801 2 locks held by getty/7862: #0: ffff8880a4c9f090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272 #1: ffffc90005f412e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156 2 locks held by getty/7863: #0: ffff8880a3e9d090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272 #1: ffffc90005f2d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156 2 locks held by getty/7864: #0: ffff88808c2ba090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272 #1: ffffc90005f3d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156 2 locks held by getty/7865: #0: ffff88809a021090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272 #1: ffffc90005f492e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156 2 locks held by getty/7866: #0: ffff8880a95c3090 (&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/7867: #0: ffff8880a05b5090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272 #1: ffffc90005f452e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156 2 locks held by getty/7868: #0: ffff88809b7b1090 (&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 1 lock held by syz-executor.3/2367: #0: ffff888097fbc428 (sb_writers#16){.+.+}, at: file_start_write include/linux/fs.h:2882 [inline] #0: ffff888097fbc428 (sb_writers#16){.+.+}, at: do_sendfile+0x7c2/0xfd0 fs/read_write.c:1463 1 lock held by syz-executor.2/2393: #0: ffff88805a006428 (sb_writers#16){.+.+}, at: file_start_write include/linux/fs.h:2882 [inline] #0: ffff88805a006428 (sb_writers#16){.+.+}, at: do_sendfile+0x7c2/0xfd0 fs/read_write.c:1463 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1067 Comm: khungtaskd Not tainted 5.4.0-rc8-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+0xbb9/0xbd0 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: 3906 Comm: udevd Not tainted 5.4.0-rc8-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__kasan_check_read+0x0/0x20 mm/kasan/common.c:91 Code: 99 ff 90 90 90 90 90 90 90 90 65 48 8b 04 25 c0 fd 01 00 ff 80 e0 12 00 00 c3 65 48 8b 04 25 c0 fd 01 00 ff 88 e0 12 00 00 c3 <55> 48 89 e5 89 f6 48 8b 4d 08 31 d2 e8 5f 23 00 00 5d c3 0f 1f 00 RSP: 0018:ffff88809649fc08 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000001 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff88be61a0 RBP: ffff88809649fc50 R08: ffffffff83489c7a R09: 0000000000000001 R10: fffffbfff117cc35 R11: 0000000000000000 R12: dffffc0000000000 R13: ffffffff81583ff0 R14: ffff888096599d38 R15: ffff888097ab1c28 FS: 00007f285c1c47a0(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000045a60f CR3: 0000000096af4000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x125/0x250 kernel/locking/lockdep.c:4486 __raw_write_lock_irq include/linux/rwlock_api_smp.h:196 [inline] _raw_write_lock_irq+0x6a/0x80 kernel/locking/spinlock.c:311 ep_scan_ready_list+0x330/0x980 fs/eventpoll.c:706 ep_send_events fs/eventpoll.c:1793 [inline] ep_poll+0xb85/0xe80 fs/eventpoll.c:1930 do_epoll_wait+0x1ee/0x260 fs/eventpoll.c:2294 __do_sys_epoll_wait fs/eventpoll.c:2304 [inline] __se_sys_epoll_wait fs/eventpoll.c:2301 [inline] __x64_sys_epoll_wait+0x9a/0xb0 fs/eventpoll.c:2301 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f285b8d8943 Code: 00 31 d2 48 29 c2 64 89 11 48 83 c8 ff eb ea 90 90 90 90 90 90 90 90 83 3d b5 dc 2a 00 00 75 13 49 89 ca b8 e8 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 34 c3 48 83 ec 08 e8 3b c4 00 00 48 89 04 24 RSP: 002b:00007ffcae67c3f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e8 RAX: ffffffffffffffda RBX: 0000000000000bb8 RCX: 00007f285b8d8943 RDX: 0000000000000008 RSI: 00007ffcae67c4f0 RDI: 000000000000000a RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000bb8 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000000000000 R14: 0000000001758050 R15: 0000000001746250