INFO: task syz-executor.5:22220 blocked for more than 143 seconds. Not tainted 5.6.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28072 22220 1 0x00004004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4080 schedule+0xdc/0x2b0 kernel/sched/core.c:4154 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4213 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 lock_fb_info include/linux/fb.h:637 [inline] fb_release+0x55/0x150 drivers/video/fbdev/core/fbmem.c:1447 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath arch/x86/entry/common.c:278 [inline] do_syscall_64+0x676/0x790 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x415fc1 Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 1b 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007ffcf0821fd0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000415fc1 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 0000000000000001 R08: 000000003f6720f9 R09: 000000003f6720fd R10: 00007ffcf08220b0 R11: 0000000000000293 R12: 000000000076c920 R13: 000000000076c920 R14: 000000000009255b R15: 000000000076bfcc INFO: task syz-executor.4:22245 blocked for more than 143 seconds. Not tainted 5.6.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D29704 22245 1 0x00004004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4080 schedule+0xdc/0x2b0 kernel/sched/core.c:4154 schedule_timeout+0x717/0xc50 kernel/time/timer.c:1871 __down_common kernel/locking/semaphore.c:220 [inline] __down+0x176/0x2c0 kernel/locking/semaphore.c:237 down+0x64/0x90 kernel/locking/semaphore.c:61 console_lock+0x29/0x80 kernel/printk/printk.c:2289 do_fb_ioctl+0x335/0x7d0 drivers/video/fbdev/core/fbmem.c:1106 fb_ioctl+0xe6/0x130 drivers/video/fbdev/core/fbmem.c:1185 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x123/0x180 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c429 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f5cd6a20c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f5cd6a216d4 RCX: 000000000045c429 RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000005 RBP: 000000000076c060 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000002ef R14: 00000000004c5056 R15: 000000000076c06c INFO: task syz-executor.3:22250 blocked for more than 143 seconds. Not tainted 5.6.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D26936 22250 1 0x00004004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4080 schedule+0xdc/0x2b0 kernel/sched/core.c:4154 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4213 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0xd7/0x450 drivers/video/fbdev/core/fbmem.c:1418 chrdev_open+0x245/0x6b0 fs/char_dev.c:414 do_dentry_open+0x4e6/0x1380 fs/open.c:797 vfs_open+0xa0/0xd0 fs/open.c:914 do_last fs/namei.c:3490 [inline] path_openat+0x12ee/0x3490 fs/namei.c:3607 do_filp_open+0x192/0x260 fs/namei.c:3637 do_sys_openat2+0x5eb/0x7e0 fs/open.c:1149 do_sys_open+0xf2/0x180 fs/open.c:1165 __do_sys_openat fs/open.c:1179 [inline] __se_sys_openat fs/open.c:1174 [inline] __x64_sys_openat+0x9d/0x100 fs/open.c:1174 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c429 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f0a1a5eac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f0a1a5eb6d4 RCX: 000000000045c429 RDX: 0000000000000000 RSI: 0000000020000180 RDI: ffffffffffffff9c RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000799 R14: 00000000004ca08e R15: 000000000076bf2c INFO: task syz-executor.2:22252 blocked for more than 143 seconds. Not tainted 5.6.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28304 22252 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4080 schedule+0xdc/0x2b0 kernel/sched/core.c:4154 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4213 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0xd7/0x450 drivers/video/fbdev/core/fbmem.c:1418 chrdev_open+0x245/0x6b0 fs/char_dev.c:414 do_dentry_open+0x4e6/0x1380 fs/open.c:797 vfs_open+0xa0/0xd0 fs/open.c:914 do_last fs/namei.c:3490 [inline] path_openat+0x12ee/0x3490 fs/namei.c:3607 do_filp_open+0x192/0x260 fs/namei.c:3637 do_sys_openat2+0x5eb/0x7e0 fs/open.c:1149 do_sys_open+0xf2/0x180 fs/open.c:1165 __do_sys_openat fs/open.c:1179 [inline] __se_sys_openat fs/open.c:1174 [inline] __x64_sys_openat+0x9d/0x100 fs/open.c:1174 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c429 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f1b92ecbc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f1b92ecc6d4 RCX: 000000000045c429 RDX: 0000000000000000 RSI: 0000000020000180 RDI: ffffffffffffff9c RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000799 R14: 00000000004ca08e R15: 000000000076bf2c Showing all locks held in the system: 2 locks held by kworker/u4:5/252: 1 lock held by khungtaskd/475: #0: ffffffff89bac240 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 kernel/locking/lockdep.c:5333 1 lock held by rsyslogd/10690: #0: ffff8880a4b400e0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:821 2 locks held by getty/10812: #0: ffff88809200e090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000560b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10813: #0: ffff8880a681a090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900055f32e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10814: #0: ffff8880886e4090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000561b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10815: #0: ffff888093c2b090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900056132e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10816: #0: ffff8880995b5090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900056072e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10817: #0: ffff8880a6d38090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900056032e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10818: #0: ffff888096c90090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900055a32e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.5/22220: #0: ffff8880a393c070 (&fb_info->lock){+.+.}, at: lock_fb_info include/linux/fb.h:637 [inline] #0: ffff8880a393c070 (&fb_info->lock){+.+.}, at: fb_release+0x55/0x150 drivers/video/fbdev/core/fbmem.c:1447 2 locks held by syz-executor.0/22240: 1 lock held by syz-executor.3/22250: #0: ffff8880a393c070 (&fb_info->lock){+.+.}, at: lock_fb_info include/linux/fb.h:637 [inline] #0: ffff8880a393c070 (&fb_info->lock){+.+.}, at: fb_open+0xd7/0x450 drivers/video/fbdev/core/fbmem.c:1418 1 lock held by syz-executor.2/22252: #0: ffff8880a393c070 (&fb_info->lock){+.+.}, at: lock_fb_info include/linux/fb.h:637 [inline] #0: ffff8880a393c070 (&fb_info->lock){+.+.}, at: fb_open+0xd7/0x450 drivers/video/fbdev/core/fbmem.c:1418 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 475 Comm: khungtaskd Not tainted 5.6.0-rc2-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+0x197/0x210 lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xb11/0x10c0 kernel/hung_task.c:289 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 252 Comm: kworker/u4:5 Not tainted 5.6.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: krdsd rds_connect_worker RIP: 0010:__lock_acquire+0x1a2f/0x4a00 kernel/locking/lockdep.c:3950 Code: 07 00 00 48 69 db b0 00 00 00 48 81 c3 80 af 51 8b 48 8d 7b 40 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 c9 23 00 00 48 83 7b 40 00 0f 85 07 ee ff ff 0f 0b e9 00 ee RSP: 0018:ffffc90001b77840 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffffffff8b5482c0 RCX: ffffffff815ae65c RDX: 1ffffffff16a9060 RSI: 0000000000000008 RDI: ffffffff8b548300 RBP: ffffc90001b77958 R08: 1ffffffff16a357c R09: fffffbfff16a357d R10: ffff8880a92b2eb8 R11: ffff8880a92b2580 R12: 00000000bc690817 R13: ffffffff8aa5e290 R14: ffff8880a92b2e90 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000000a0706000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4484 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x33/0x50 kernel/locking/spinlock.c:175 spin_lock_bh include/linux/spinlock.h:343 [inline] inet_csk_find_open_port net/ipv4/inet_connection_sock.c:218 [inline] inet_csk_get_port+0xbeb/0x24b0 net/ipv4/inet_connection_sock.c:300 __inet_bind+0x5bf/0xbf0 net/ipv4/af_inet.c:524 inet_bind+0xfa/0x160 net/ipv4/af_inet.c:453 rds_tcp_conn_path_connect+0x536/0x880 net/rds/tcp_connect.c:144 rds_connect_worker+0x1b6/0x2d0 net/rds/threads.c:176 process_one_work+0xa05/0x17a0 kernel/workqueue.c:2264 worker_thread+0x98/0xe40 kernel/workqueue.c:2410 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352